HomeMy WebLinkAboutSurface Water Supply Protection Plan for Lily Pond and Aaron River Reservoir (PDF)i
Project No. 99-04 SWT
(NRG Project No. 462.1)
June 2002
Prepared for:
Massachusetts Department of
Environmental Protection
Bureau of Resource Protection
One Winter Street
Boston, MA 02164
and
U.S. Environmental Protection
Agency - Region 1
Prepared by:
Norfolk Ram Group, LLC
One Roberts Drive
Plymouth, MA 02360
and
100 Kuniholm Drive
Holliston, MA 01746
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TABLE OF CONTENTS
LIST OF TABLES, FIGURES, APPENDICES
ACKNOWLEDGEMENTS
1.0 EXECUTIVE SUMMARY...................................................................................1-1
2.0 INTRODUCTION ...............................................................................................2-1
2.1 Background and Benefits.....................................................................2-1
2.2 Purpose..................................................................................................2-3
2.3 Watershed Description.........................................................................2-5
2.4 Organization of SWSPP Report ...........................................................2-8
3.0 LAND USE IMPACTS .......................................................................................3-1
3.1 Water Supply Impacts from Existing Land Uses ................................3-1
3.1.1 Spills And State 21E Sites.........................................................3-2
Hingham Training Annex Disposal Site – State 21E Site........3-3
Former Beechwood Dump – State 21E Site.............................3-4
Former Norfolk Conveyor Site – State 21E Site.......................3-4
Former Burning Ground – State 21E Site.................................3-6
35 Arrowwood Street, Cohasset – Spills Site. .........................3-7
Beechwood Street, Cohasset – Spills Site...............................3-7
Schofield Road, Cohasset – Spills Site....................................3-8
422 King Street, Cohasset – Spills Site....................................3-8
King Street, Cohasset – Spills Site...........................................3-8
Flint Rock Road, Cohasset – Spills Site...................................3-8
3.1.2 Waste Disposal Facilities...........................................................3-8
Cohasset Heights Landfill. ........................................................3-8
Former Clapp Landfill. .............................................................3-11
3.1.3 Use and Storage of Hazardous Materials...............................3-12
3.1.4 Untreated Stormwater Runoff .................................................3-14
3.1.5 Septic Systems.........................................................................3-16
3.1.6 State and Municipal Land and Facilities.................................3-19
Massachusetts Highway Department.....................................3-19
Cohasset Water Treatment Plant. ...........................................3-20
Cemeteries................................................................................3-21
Town Parks...............................................................................3-21
3.1.7 Industrial Wastewater Discharge............................................3-21
3.1.8 Public and Private Recreation.................................................3-22
3.1.9 Electric Transmission Line Right-of-Way...............................3-22
3.1.10 Forestry Practices ....................................................................3-23
DEM Land Management...........................................................3-23
Woody Adelgid Infestation. .....................................................3-24
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3.1.11 Storage of Fertilizer, Manure, Road Salt.................................3-24
3.1.12 New Construction.....................................................................3-25
3.1.13 Sand and Gravel Mining/Washing Operations.......................3-25
3.2 Water Supply Impacts from Future Land Use...................................3-25
3.2.1 Protected Areas, Open Space and Municipal Zoning
within the Watershed ...............................................................3-25
3.2.2 Future Land Use Impacts.........................................................3-26
3.3 Public Access/Recreation Impacts....................................................3-27
3.3.1 Public Access to Lily Pond and Aaron Reservoir..................3-27
3.4 Wildlife Impacts...................................................................................3-27
3.4.1 Existing or Potential Water Supply Impacts from Wildlife....3-27
3.4.2 Existing or Potential Water Supply Impacts from Domestic
Animals .....................................................................................3-28
3.5 In-Lake Problems................................................................................3-28
3.5.1 Existing or Potential In-Lake Problems..................................3-28
3.6 Other Areas of Concerns ....................................................................3-29
4.0 SAMPLING PLAN.............................................................................................4-1
4.1 Previous Surface Water Sampling.......................................................4-1
4.2 Short-Term Sampling............................................................................4-3
4.3 Proposed Long-Term Sampling Plan ..................................................4-1
4.3.1 Surface Water.............................................................................4-1
4.3.2 Groundwater – Bedrock Pathways ...........................................4-1
5.0 LAND USE CONTROLS ...................................................................................5-1
5.1 Land Purchase or Deed Restriction ....................................................5-1
5.2 ACECs and Protected Open Spaces ...................................................5-3
5.3 Land Use and Activity Controls...........................................................5-4
5.3.1 Septic Systems...........................................................................5-4
5.3.2 Stormwater Runoff.....................................................................5-5
No-Salt Zones.............................................................................5-5
Stormwater Drainage. ................................................................5-5
5.4 Municipal Land Use Improvements.....................................................5-6
5.4.1 Water Treatment Plant Improvements......................................5-6
Off-site Disposal of Wastewater and Sludge. ..........................5-6
5.5 Lawn Management................................................................................5-6
5.6 Management Plan..................................................................................5-7
6.0 PUBLIC ACCESS/ RECREATION CONTROL .................................................6-1
6.1 Public Access to Water Supply Areas.................................................6-1
6.2 Recreation Control................................................................................6-1
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6.3 Wildlife Management ............................................................................6-1
6.3.1 Canadian Geese .........................................................................6-1
6.4 In-Lake Management.............................................................................6-2
6.4.1 Limnology Study of the Pond and Reservoir...........................6-2
6.4.2 Annual Eutrophication Assessment .........................................6-2
7.0 REGULATORY CONTROLS .............................................................................7-1
7.1 Current Local Water Resources Protection Regulations ..................7-1
7.1.1 Zoning By-laws...........................................................................7-1
Open Space.................................................................................7-1
Residential..................................................................................7-1
Commercial/Technology Business...........................................7-1
7.1.2 Water Resources Protection Districts......................................7-1
Regulatory Protection................................................................7-2
7.1.3 Conservation Commission Bylaws...........................................7-4
Cohasset’s Wetlands Bylaw......................................................7-4
Norwell’s Wetlands Bylaw.........................................................7-4
Buffer Zone.................................................................................7-4
Fifty Foot (50’) Buffer Strip Regulation.....................................7-4
Scituate’s Wetlands Bylaw........................................................7-4
7.1.4 Activities Requiring Special Permits........................................7-5
7.1.5 Hazardous Materials Restrictions.............................................7-5
7.1.6 Title 5 Septic System Regulations............................................7-6
7.2 State Regulations..................................................................................7-6
8.0 EMERGENCY PLANNING ................................................................................8-1
8.1 Emergency Response Plans................................................................8-1
8.2 Emergency Response Training............................................................8-2
9.0 EDUCATION PROGRAM..................................................................................9-1
9.1 Objective of the Education Program...................................................9-1
9.2 Implementation......................................................................................9-1
9.3 Public Outreach and Education...........................................................9-1
9.4 Intercommunity Partnership ................................................................9-2
9.5 SWSPP Information ..............................................................................9-2
10.0 SUMMARY OF RECOMMENDATIONS..........................................................10-1
10.1 General.................................................................................................10-1
10.2 Watershed Monitoring and Assessment (Group A).........................10-1
10.3 Stormwater and Non-Point Source Pollution
Controls (Group B)..............................................................................10-2
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10.4 Septic System and Other Point Source Pollution
Controls (Group C)..............................................................................10-4
10.5 Land Use Bylaws, Management and Enforcement
Funding (Group D)..............................................................................10-5
10.6 Open Space Acquisition and Conservation Restrictions
(Group E) .............................................................................................10-6
10.7 Watershed Management (Group F)....................................................10-6
List of Tables Page
Table 2-1 Breakdown of Surface Water Supply Watershed Areas 2-3a
Table 3-1 DEP Land Use Matrix Ranking 3-1a
Table 3-2 Number and Type of Septic Systems by Zone 3-15a
Table 4-1 Short-Term Sampling Plan Locations and Parameters 4-3a
Table 4-2 Quarterly Water Sampling results 4-4a-e
Table 4-3 Long-Term Sampling Plan Locations and Parameters 4-4s
Table 7-1 Prohibited Uses in Water Resources Protection Districts 7-2a
Table 9-1 Proposed Education Program Activities for the Surface
Water Supply Protection Plan 9-2a
Table 10-1 Summary of Recommendations 10-1a
Table 10-2 Implementation Schedule for Recommendations 10-1b
List of Figures Page
Figure 1 Site Locus Map 2-1a
Figure 2 Water Resources Protection Districts 3-12a
Figure 3 Surface Water Dissolved Oxygen 4-4f
Figure 4 Surface Water pH (1999) 4-4g
Figure 4a Surface Water pH (2000-2002) 4-4h
Figure 5 Surface Water Conductivity 4-4i
Figure 6 Surface Water Temperature 4-4j
Figure 7 Surface Water Turbidity 4-4k
Figure 8 Surface Water Alkalinity 4-4l
Figure 9 Surface Water COD 4-4m
Figure 10 Surface Water Chloride 4-4n
Figure 11 Surface Water Fecal Coliform Counts 4-4o
Figure 12 Surface Water Orthophosphate 4-4p
Figure 13 Surface Water Total Phosphorus 4-4q
Figure 14 Surface Water Total Keldahl Nitrogen 4-4r
Figure 15 Developable Parcels Located in (or abutting) Zone A 5-1a
List of Appendices
Appendix A
Thematic Data Layers Portrayed on the GIS Maps
List of Assessor Parcels Categorized as Undeveloped Land by the Town
of Cohasset Assessor’s Office
Map 1a Land Use
Map 1b Potential Threats to the Watershed
Map 2 Protected Areas. Open Space, and Municipal Zoning
Map 3 Undevelopable Land Practices
Map 4 Parcels of Unknown Ownership
Appendix B
Land Use Pollution Potential Matrix
DRAFT Land Use/Associated Contaminants Matrix
Quality Assurance Project Plan
Model Zone A Bylaw Revisions Proposed for Cohasset
Inventory of Stormwater Drainage Systems Tributary to Lily Pond (Norfolk
Ram Group Memo dated 04/02/02)
ACKNOWLEDGEMENTS
This project has been financed partially with Federal funds from the United States
Environmental Protection Agency (USEPA) to the Massachusetts Department of
Environmental Protection (DEP) under the Source Water Protection Technical
Assistance/Land Management Grant Program. The contents do not necessarily reflect
the views and policies of USEPA or DEP, nor does the mention of any trade names or
commercial products constitute endorsement or a recommendation for use.
We would like to acknowledge the following for their ready assistance in providing
information used in this report.
Town of Cohasset: Board of Water Commissioners; John McNabb, Jr.,
Chairman, Rob Kasameyer and Glenn Pratt
Board of Health; Dr. Joseph Godzik and Tara Mullen
Conservation Commission; Paul Shea and Deborah Cook
Planning Department; Elizabeth Harrington
Watershed Committee; James Kinch
Town of Hingham: Conservation Commission; Cliff Prentice
Hingham Fire Department; Mark Duff
Wompatuck State Park; Steve Gammon
Town of Norwell: Board of Health; Brian Flynn
Town of Scituate: Water Division; Gene Babin
Conservation Commission; Vincent Kalishes and Allan
Mayberry Greenberg
First Herring Brook Watershed Initiative; Lance Van Lenten,
Director
Town Planner; Laura Harbottle
Department of Public Works; Anthony Antoniello, Director
State of Massachusetts: South Coastal Watershed Coordinator; Dr. George Zoto
1.0 EXECUTIVE SUMMARY
Protecting the drinking water supplies of the Commonwealth of Massachusetts is of
major interest to federal, state and local groups. These resources are recognized as
“one-of-a-kind”, and once lost to pollution, irreplaceable in the short term. The Town of
Cohasset supplies drinking water for 90% of its residents from Lily Pond, which
sometimes draws water from the Aaron River Reservoir, and Cohasset has been very
proactive in the effort to protect these resources. The Massachusetts Department of
Environmental Protection, in cooperation with the United States Environmental
Protection Agency, has provided funding to Norfolk Ram Group, LLC for the
development of this Surface Water Supply Protection Plan (SWSPP). The organization
of this report is consistent with the Department of Environmental Protection’s May 2000
guidance document titled Developing a Local Surface Water Supply Protection Plan.
The purpose of this SWSPP is to compile, organize and present information that
describes the watershed, and present a plan to identify, prevent, eliminate and control
actual or potential sources of contamination that could negatively impact the quality of
the drinking water supply that is available from Lily Pond and the Aaron River Reservoir.
The plan is intended to form a base of understanding and a starting point for watershed
protection, education, and management as a dynamic process going forward. It is
expected that this SWSPP will be used as a management and planning tool primarily by
the Cohasset Board of Water Commissioners, which is the leading local authority with
responsibility for protecting the water supply and associated watershed.
Lily Pond and the Aaron River Reservoir are hydrologically linked by the Bound Brook
Control Structure, which is used to raise the surface water elevation on the upstream
side of the structure to equal that of the surface elevation of Lily Pond. This creates
storage in the wetlands located south of Lily Pond that can be called upon when the
demand for water from the pond is greatest, typically in the summer months. It also
links the subbasins associated with the two surface water bodies forming a much larger
contributory Watershed located across four communities: Cohasset (38%), Norwell
(33%), Hingham (18%), and Scituate (11%). In Massachusetts, the area of a watershed
is divided into three zones: Zone A which is a narrow strip of land along the shoreline of
the surface water supply and tributaries (200 and 400 feet, respectively); Zone B which
is the area within ½ miles of the shoreline of the surface water bodies; and Zone C
which is the remainder of the Watershed. The regional nature of the Watershed
necessitates an inter-community approach to protecting Cohasset’s surface water
supply since activities anywhere in the Watershed can potentially negatively impact Lily
Pond.
As part of this SWSPP, five large-scale maps were produced depicting certain aspects
of the Watershed. These maps were developed using information from geographical
information systems, topographical maps and existing watershed maps. The maps
show the land use, potential threats to the Watershed, protected areas, Open Space,
and municipal zoning, undevelopable land parcels, and parcels of unknown ownership.
These maps represent the base conditions of the Watershed at the creation of this
SWSPP, and they can be used in the future as a benchmark from which to compare the
protection and development of the Watershed.
There are many existing and potential future threats to Cohasset’s surface water supply
mainly associated with certain land uses such as locations where a release to the
environment of oil or hazardous materials has occurred, landfills and dumps, military
facilities, commercial and industrial facilities, municipal facilities, etc. These land uses
typically involve activities that require the use, production, or storage of potential
contaminants, which, if managed improperly, could adversely impact the environment
including soil, groundwater, surface water and air. The DEP has cataloged most types
of land use in their 1999 Land Use Pollution Potential Matrix (the DEP Matrix)
developed for the Source Water Assessment Program. The DEP Matrix categorizes
land uses and ranks them High, Moderate or Low relative to the threat they pose to the
water quality of a water supply. Information in the DEP Matrix and DEP’s 1999 DRAFT
Land Use/Associated Contaminants Matrix, which lists the types of contaminants
typically associated with land uses, provides the basis for much of the discussion of
land uses in this SWSPP.
Impacts to Lily Pond and the Aaron River Reservoir associated with non-point source
pollution are probably the single greatest immediate threat to the water quality of the
surface water supply. Non-point source pollution is associated with untreated
stormwater runoff, on-site septic systems, fertilizer, pesticide and herbicide use, and
destruction of natural buffer zones around surface water bodies and tributaries. For
instance, over the past few years, sodium concentrations in the pond have exceeded
the state recommended guideline concentration partially due to the use of salt-based
deicing chemicals on roads where drainage systems are tributary to the surface water
supply. Non-point source pollution is also manifest in the concentration of nutrients that
enter the pond. An evaluation of existing surface water data conducted as part of this
SWSPP suggests both Lily Pond and the Aaron River Reservoir are eutrophic to hyper-
eutrophic in terms of nutrient loading and the potential for uncontrolled plant growth.
These nutrients have several non-point sources including untreated stormwater runoff,
and antiquated on-site septic systems. The causes of eutrophication, mainly excess
nitrates and phosphates are also known to be detrimental to human health, and
eutrophication can lead to the eventual loss of a water body through siltation.
Many of the threats to the surface water supply can be minimized by zoning and non-
zoning controls that prohibit certain land uses within the Watershed. First, the threats
need to be identified and then prioritized in order of their immediacy to the protection of
the Watershed. This SWSPP forms the base for this type of evaluation. The degree of
protection of the Watershed should be greatest closest to the surface water supply and
tributaries (Zone A) and less stringent farther away (Zones B and C). Fortunately, all of
the communities within the Watershed have some type of land use control in the form of
Water Resources Protection Districts. In addition, much of the Watershed is protected
as Open or Recreational Space such as Wompatuck State Park and land owned by the
Trustee of Reservations1, which together accounts for approximately 40% of the area of
the Watershed. These forms of land use and land use controls are very protective of
the Watershed. However, this does not preclude taking additional actions to ensure
long-term Open Space/Conservation restrictions as are recommended in this report.
The protection of the Watershed can be greatly enhanced by the institution of land use
controls such as land purchase or deed restrictions, designation of Areas of Critical
Environmental Concern, activity controls such as septic system management,
stormwater control, declaring section of roads no-salt zones, and lawn management
programs. These land use control issues are discussed in detail in this SWSPP.
Regulatory controls are also discussed as a means to manage activities within the
Watershed so that the long-term viability of the surface water supply is maintained.
In order to provide a good indication of the success of the Watershed protection efforts
and to monitor known contaminants of concern and the trophic state of Lily Pond, a
Long-Term Sampling Plan should be implemented. This SWSPP recommends
quarterly sampling at eleven surface water sampling points at Lily Pond, the Aaron
River Reservoir and their tributaries.
Much of the historic water quality data that exists for the Watershed has been collected
between Lily Pond and the Cohasset Heights Landfill site. A 1998 study by Norfolk
Environmental evaluated this data and the potential for contamination of the watershed
by CHL landfill. The 1998 Norfolk study found that groundwater transport is a viable
potential threat to the Watershed since significant water bearing bedrock fractures were
found to exist that could channel contaminants from the Landfill to Brass Kettle Brook
and into Lily Pond. For this reason, several deep bedrock wells were installed to
intercept the water bearing bedrock fractures and quarterly monitoring was initiated for
volatile organic compounds, chemical oxygen demand, chloride, and the five “landfill”
metals (antimony, arsenic, cadmium, chromium, and lead). To date, testing of these
bedrock wells (there are three) has not indicated that contamination migration is
occurring through bedrock fractures, although there have been some isolated detections
of contaminants2. For this reason, these wells should be monitored quarterly at least for
the next two (2) years.
Finally, the SWSPP offers recommendations and a prioritization for implementation
based upon the relative importance of each to watershed protection. The
recommendations are grouped into the following categories in order of importance of
implementation: Watershed Monitoring and Assessment; Stormwater and Non-Point
Source Pollution Controls; Septic System and Other Point Source Pollution Controls;
Land Use Bylaws, Management, and Enforcement Funding; Open Space Acquisition
and Conservation Restrictions; and Watershed Management. Immediate
1 The Trustee of Reservations is a conservation group that by its Charter purchases and protects land by
ownership where no other means of protection may exist.
2 To date, testing has found a one-time (3rd Quarter 2001) elevated level of antimony that exceeded the
Massachusetts Maximum Contamination Level and also for the same quarter elevated Total Dissolved
Solvents. Both elevated levels were not repeated in later quarterly testing.
implementation of the first two categories is considered very important to the long-term
management of the Watershed.
2.0 INTRODUCTION
This Surface Water Supply Protection Plan (SWSPP) is for Lily Pond, the Aaron River
Reservoir and their associated tributaries and sub-watersheds, hereinafter collectively
referred to as the “Watershed”. Lily Pond is the Town of Cohasset’s primary public
water supply. As such, it is an Outstanding Resource Water and a Class A water body.3
In addition, the Aaron River Reservoir and all tributaries associated with Lily Pond and
the reservoir are also classified as Outstanding Resource Waters/Class A water bodies.
The locations of Lily Pond and the Aaron River Reservoir are shown on Figure 1.
The Massachusetts Surface Water Quality regulation states “Outstanding Resource
Waters are determined by their outstanding socioeconomic, recreational, ecological
and/or aesthetic values. The quality of these waters shall be protected and maintained”.
Discharges to these waters are prohibited without a variance from the DEP. Class A
waters are designated as a source of public water supply. To the extent compatible
with the use they shall be an excellent habitat for fish, other aquatic life and wildlife, and
suitable for primary and secondary recreation, and have excellent aesthetic value.
2.1 Background and Benefits
The SWSPP has been prepared according to a defined scope of work and budget
approved by the Massachusetts Department of Environmental Protection (DEP), and as
noted in the Acknowledgements, was funded under a grant issued through DEP’s
Source Water Protection Technical Assistance / Land Management Grant Program.
The SWSPP is closely related to the following two state programs that have been
established to assess and manage water resources in the Commonwealth:
x First, the Executive Office of Environmental Affairs (EOEA) has
established watershed teams that have been implementing a “Watershed
Initiative” program for the 27 river basins in the Commonwealth. The
purpose of the EOEA program is to collect and share water resource
information, assess impacts, and develop and implement activities to
protect and improve water resources on a 5-year cyclical program.
x Secondly, the DEP is required by federal law to conduct a Source Water
Assessment Program (“SWAP”) to determine the susceptibility of the
3,000 Massachusetts public drinking water sources to potential
contamination.
This SWSPP will provide these two state agencies and the Cohasset Board of Water
Commissioners with needed information about the Lily Pond/Aaron River Reservoir
Watershed.
There are, of course significant local benefits that derive from preparing and
implementing the SWSPP, and these include:
3 Massachusetts Surface Water Quality Standards (314 CMR 4.00)
x Protection of the public health from contamination of the public drinking
water supply;
x Increased protection of the water supply from waterborne diseases and
other contaminants injurious to public health;
x Reduction in water treatment costs, since cleaner source water requires
less expensive treatment efforts;
x Increased longevity of the water supply due to reduction in pond
eutrophication, and protection and conservation of watershed source
areas that generate the annual volumes of source waters; and
x Increased public awareness and public management of clean water as a
valued resource.
2.2 Purpose
This plan is not intended to be a comprehensive technical study of watershed dynamics,
or a study of all the complex biological, physical, chemical and ecological processes that
affect the Watershed and water supply quality. Rather, the intent of this SWSPP is to
compile, organize and present information that describes the Watershed, and present a
plan to identify, prevent, eliminate and control actual or potential sources of
contamination that could negatively impact the quality of the drinking water supply that
is available from Lily Pond and the Aaron River Reservoir.
Basically, the goals of this report are three fold:
1. Delineate, map, and characterize the surface water supply Watershed, taking
inventory of watershed resources and the existing and potential land uses that
affect those resources;
2. Identify sources of existing and potential pollutants and land use threats to the
surface water supply; and
3. Develop a plan that local authorities and stakeholders can use as a tool to
manage and improve Watershed protection in the future.
The plan is intended to form a base of understanding and a starting point for watershed
protection, education, and management as a dynamic process going forward. As such,
the SWSPP presents numerous recommendations for future action. Some of the
recommended actions involve on-going monitoring of the Watershed (e.g. long term
sampling/testing plan), some involve more detailed study for better understanding of the
resource areas (e.g., limnology study of Lily Pond and Aaron River Reservoir), some
call for implementation of protective measures (e.g., engineering and construction of
controls for non-point source stormwater pollution), and some call for
institutional/regulatory changes (e.g., passing of local bylaws for watershed protection).
It is expected that this SWSPP will be used as a management and planning tool
primarily by the Cohasset Board of Water Commissioners, which is the leading local
authority with responsibility for protecting the water supply and associated Watershed.
However, successful watershed management and protection will require assistance and
support from a variety of town officials and citizen groups within the Watershed member
communities.
Table 2-1
BREAKDOWN OF SURFACE WATER SUPPLY WATERSHED AREAS
AREA TOWN
Area
(acres)
Area
(sq. miles)
Aaron River Reservoir Sub-Basin Norwell 1,983 3.09
Hingham 513 0.80
Scituate 546 0.85
Cohasset 228 0.35
Sub-Total 3270 5.09
Lily Pond Reservoir Sub-Basin Cohasset 1,321 2.06
Hingham 322 0.50
Sub-Total 1,643 2.56
Bound Brook Sub-Basin Cohasset 763 1.19
Hingham 234 0.36
Scituate 90 0.14
Sub-Total 1,087 1.69
TOTAL Cohasset 2,312 3.61 (38%)
Norwell 1,983 3.09 (33%)
Hingham 1,069 1.67 (18%)
Scituate 636 0.99 (11%)
TOTAL 6,000 9.37
2.3 Watershed Description
The Watershed is defined as that area of land that by its topography contributes all of
the water that recharges these surface water bodies. The Watershed is located
approximately 25 miles south of Boston and comprises portions of several sub-basins,
which are all part of the South Coastal major watershed basin. Maps 1a, 1b, and 2
included in Appendix A, show the delineation of the Watershed boundary, which was
determined from Massachusetts Geographic Information System (MassGIS) maps,
Cohasset Water Commission GIS maps, United States Geological Survey (USGS)
topographical maps, local topographical maps, and watershed maps from previous
studies of the Watershed. The Watershed covers an area of 6,000 acres, or 9.4 square
miles. Thirty-eight percent of the Watershed is located in Cohasset; 33% is located in
Norwell; 18% is located in Hingham; and 11% is located in Scituate.4 A more detailed
breakdown of watershed areas by sub-basin is provided in Table 2-1.
Lily Pond is located entirely in the Town of Cohasset, and has a surface area of
approximately 52 acres and a reported average depth of 9 feet. Based upon this
information, Lily Pond impounds approximately 150 million gallons of water. According
to other published reports, the storage capacity of the pond is as much as 170 million
gallons of water. There are two main tributaries to Lily Pond: Peppermint Brook flows
into Lily Pond from the north; and Brass Kettle Brook from the west. Herring Brook
located south of the pond, sometimes serves as a tributary. The natural flow through
Herring Brook is towards the south however, during periods of increased withdrawal and
minimum recharge by precipitation, Herring Brook flows into Lily Pond from the south.
The Town of Cohasset has used Lily Pond as a drinking water supply since the 1880s.
From approximately 1880 to 1909, water was withdrawn at the north side of the pond
and pumped directly into the existing water distribution system. In 1909 the town
started to draw water from the south side of the pond and pipe it to a water treatment
plant located at the end of what is today called Riverview Drive. In 1978 a new water
treatment plant was completed on the northwest shore of the pond with access off King
Street. This plant has a design capacity of 3.0 million gallons per day, with an actual
current capacity of approximately 2.5 million gallons per day, and it currently treats and
supplies an average of 710,000 gallons per day of potable water to over 7,100 residents
(90%) of the Town of Cohasset.
The Aaron River Reservoir is located approximately one mile south of Lily Pond, mostly
in the Town of Cohasset, with minor portions in the towns of Hingham and Scituate. It
has a surface area of approximately 133 acres and impounds approximately 323 million
gallons of water. It was created in 1978 by the construction of an earthen dam just west
of the intersection of Beechwood and Summer Streets. This dam controls flow in the
Aaron River, which flows from the south and is the main tributary to the Aaron River
4 The portion within Scituate was updated (increased) as part of this study based on Norfolk Ram Group’s
confirmation of new delineation information received from the First Herring Brook Watershed Initiative,
Scituate, MA.
Reservoir. An unnamed stream, referred to locally as Bound Brook Stream, which flows
from Bound Brook Pond located approximately 2,000 feet south of the reservoir in the
town of Norwell, converges with the Aaron River south of the reservoir. There is one
other tributary to the reservoir: an unnamed stream referred to as the South Swamp
tributary by the First Herring Brook Watershed Initiative and hereinafter, flows into the
reservoir from the southeast. The USGS and MassGIS maps show the head of this
stream located near Thomas Clapp Road. However, the work conducted by the First
Herring Brook Watershed Initiative indicates the stream may extend south of Thomas
Clapp Road and drain some of South Swamp in Scituate.
The outflow from the Aaron River Reservoir is controlled mainly by a fish ladder at the
Aaron River Reservoir dam. The fish ladder has a slide valve that can be adjusted
vertically to manage flow over the ladder and into the Aaron River, which flows from the
reservoir towards the north.
The Aaron River becomes Bound Brook at the convergence with Herring Brook
approximately 3,700 feet north of the dam and 1,500 feet south of Lily Pond. Herring
Brook is the natural outflow point for the pond. The flow in Bound Brook is controlled at
Beechwood Street by a sluice gate constructed in 1976 and referred to as the Bound
Brook Control Structure (BBCS). The BBCS essentially raises the surface elevation of
Bound Brook on the upstream side to the approximate surface elevation of Lily Pond.
This increases the storage capacities of Bound Brook upstream of the BBCS, Herring
Brook and the wetlands south of Lily Pond. Therefore, the BBCS creates a hydrologic
connection between Lily Pond and the Aaron River Reservoir that otherwise wouldn’t
exist, and creates a new watershed from parts of the two subbasins.
The Watershed is divided into three zones referred to as Zones A, B and C based upon
proximity to the surface water supply. According to 310 CMR 22.00, the Drinking Water
regulation:
x Zone A is defined as the land area between the surface water source and the
upper boundary of the bank; the land area within a 400 foot lateral distance from
the upper boundary of the bank of a source of public water supply (Class A
surface water source), and the land area within a 200 foot lateral distance from
the upper boundary of the bank of a tributary or associated surface water body.
x Zone B is defined as the land area within 1/2-mile of the upper boundary of the
bank of a Class A surface water source, or edge of wetland, whichever is less.
The Zone B will always include the land area within a 400-foot lateral distance
from the upper boundary of the bank of a Class A surface water source.
x Zone C is defined as the land area not designated Zone A or B within the
watershed of a Class A surface water source. These three zones are delineated
on Map 1a, Map 1b, and Map 2, and they figure prominently in the discussion of
Watershed management set forth in this SWSPP.
It should be noted that, based upon further investigation, there is a potential for
extending the Zone A along tributaries to both Lily Pond and Aaron River Reservoir.
Insufficient information exists based upon current mapping to include these areas in the
Zone A. However, further investigation may determine they fulfill the Zone A
requirements. A description of three areas identified as part of this SWSPP follows.
x Brass Kettle Brook. As it is currently delineated the Zone A for Brass
Kettle Brook terminates at a wetland area south of the Cohasset Heights
Ltd. (CHL) Landfill. Current mapping indicates the perennial flow of the
brook begins at the eastern edge of this wetland. However, there is also a
perennial stream intersecting the same wetland from the west. Based
upon topography, this western stream flows towards the wetland. If
channel flow exists between this western stream and Brass Kettle Brook,
then there is a hydrologic connection to the brook and to Lily Pond, and
the western stream should be included in the Zone A. If, however, the
wetland serves as a “sink” where surface water discharges perhaps into
bedrock fractures and no hydrologic connection exists, then the Zone A
should remain as indicated on the maps in Appendix A.
x Extension of South Swamp Tributary to Aaron River Reservoir. The
extension of the South Swamp tributary identified by the First Herring
Brook Watershed Initiative that flows into the reservoir from the southeast
may also qualify as part of the Zone A. If channel flow and a hydrologic
connection exist between the unmapped portion of the stream and the
Aaron River Reservoir, then the Zone A may extend into the South
Swamp in Scituate.
x Wetlands South of Bound Brook Pond. There is an extensive area of
wetlands located south of Bound Brook Pond in the town of Norwell, which
may include some of Burnt Plain Swamp. The degree of channelized flow
through these wetlands is unknown based upon current information and
mapping. If flow through the wetlands and under existing streets through
culverts can occur with eventual discharge into Bound Brook Pond, a
significant extension of the Zone A to the south may be appropriate.
RECOMMENDATION 2-1 The extent and direction of flow in these potential tributary
streams, and the existence of channel flow through bordering wetlands with eventual
discharge into the surface water supply or tributaries should be determined. This is
included as Recommendation 2.1 in Section 10.
In addition to the need to further define the tributaries, it has become apparent from the
development of this SWSPP that there is a lack of information concerning the flow in the
tributaries. A better understanding of flow is essential to the successful management of
the surface water supply and the Watershed. This information can be obtained by
conducting a hydrological assessment, which should include a water balance
evaluation, wetlands and wildlife inventory and stream channel characterization.
Through this effort, the relationship between the water releases at the Aaron River
Reservoir and the water withdrawals from Lily Pond can be quantified so that the
quantity and quality of the surface water supply as well as the aquatic habitats within the
system can be protected.
RECOMMENDATION 2.2 The Cohasset Board of Water Commissioners should
conduct a hydrologic assessment to include a water balance evaluation, wetlands and
wildlife inventory and stream channel characterization. As part this assessment, at least
five-stream flow and stage gauging stations should be constructed equipped with
constant recording open channel flow meters, and stream gages to measure stage.
The proposed locations for the stations are at the Aaron River downstream of the fish
ladder (at Doane Street), at the upstream side of the BBCS, at the upstream extent of
Herring Brook where it meets Lily Pond, brass Kettle Brook at Lily Pond, and
Peppermint Brook at Lily Pond. Stream flow and stage data should be collected at each
station over the course of one year to establish baseline flow data from which to monitor
changes going forward
Since the Watershed is located within several communities, this SWSPP proposes an
inter-community approach to the protection of the Watershed. It is not intended to be a
static, unchanging document, but instead represents a starting point for the cooperative
and comprehensive protection of Cohasset’s surface water supply. The plan should be
revisited at least on a three-year timeframe to evaluate the implementation schedule for
recommendations put forth within, and to identify achievements, as well as areas where
additional efforts should be focused.
2.4 Organization of SWSPP Report
The organization of this report is consistent with the DEP’s May 2000 guidance
document titled Developing a Local Surface Water Supply Protection Plan. There are 7
major sections titled Land Use Impacts, Sampling Plan, Land Use Controls, Public
Access/Recreation Controls, Regulatory Controls, Emergency Planning, and Education
Program. A Summary of Recommendations section follows the body of the report.
Throughout the report recommendations are presented where appropriate, and these
are highlighted by surrounding the text with borders as noted in the first two examples
below. In addition, all recommendations within the body of the report are also collated
in the Summary of Recommendations section at the end of the report.
RECOMMENDATION 2.3 The Town of Cohasset should establish a partnership with
the other Watershed communities based upon the common goal of protecting the
surface water supply. The intent of this partnership should be to create a forum for the
discussion of Watershed protection issues, to identify the appropriate action partner(s)
to implement Watershed initiatives and to establish specific timeframes for
implementing the initiatives developed in this SWSPP. In this regard, the South Coastal
Watershed Team could help with other Watershed Communities. The Cohasset Town
Planner has indicated several representatives from Cohasset, Scituate and Norwell are
active participants of the Team. The technical expertise of the Team coordinator and
various state representatives could be instrumental in organizing the partnership and
providing technical assistance.
RECOMMENDATION 2.4 The Cohasset Board of Water Commissioners should
revisited this SWSPP at least every three (3) years to evaluate and revise the
recommendations and the implementation schedule for recommendations, and to
identify achievements and areas where additional efforts should be focused.
3.0 LAND USE IMPACTS
It is generally accepted that the risk of a release of contaminants into the environment is
higher with certain types of land use. These land uses typically involve activities that
require the use, production, or storage of potential contaminants, which, if managed
improperly, could adversely impact the environment including soil, groundwater, surface
water and air. If these contaminants are released within the Watershed they may also
eventually impact the water quality of the surface water supply. Therefore, it is
important to develop an inventory of land use within the Watershed, so that existing or
potential threats to the surface water supply can be identified, mitigated and/or
monitored. Such an inventory was developed as part of this SWSPP from MassGIS
data and Assessor’s records, and is discussed in detail in this chapter. It is also
presented in summary form on Map 1a, Appendix A.
The DEP has cataloged most types of land use in their 1999 Land Use Pollution
Potential Matrix (the DEP Matrix) developed for the Source Water Assessment
Program. The DEP Matrix categorizes land uses and ranks them High, Moderate or
Low relative to the threat they pose to the water quality of a water supply. Information in
the DEP Matrix and DEP’s 1999 DRAFT Land Use/Associated Contaminants Matrix,
which lists the types of contaminants typically associated with land uses, provides the
basis for much of the discussion of land uses that follows. Both of these DEP
documents are included in Appendix B. If, based upon site-specific conditions, a
deviation from the DEP-designated risk level was justified; the reasons for the
suggested change in rank are discussed. The DEP Matrix categories for certain land
uses within the Watershed are presented in Table 3-1 along with the specific rankings
as developed in this SWSPP for the subject watershed.
The discussion of land use impacts which follows is organized under six (6) main
headings and these are:
1. Water Supply Impacts from Existing Land Use;
2. Water Supply Impacts from Future Land Use;
3. Public Access and Recreation Impacts;
4. Wildlife Impacts;
5. In-Lake Problems, and
6. Other Areas of Concern.
3.1 Water Supply Impacts from Existing Land Uses
The above noted DEP Matrix and knowledge of site-specific conditions were used to
rank existing land uses within the Watershed as High, Moderate, or Low relative to the
threat they pose to the surface water supply. The land uses that pose potential threats
to the Watershed are shown on Map 1b, Appendix A. The discussion which follows
presents information on Spills and State 21E5 Sites; waste disposal facilities; use and
5 Chapter 21E of the Massachusetts General Laws is titled Massachusetts Oil and Hazardous Material
Release Prevention and Response Act.
storage of hazardous materials; untreated stormwater runoff; septic systems; state and
municipal facilities; industrial wastewater discharge; public and private recreation;
electric transmission line right-of-way; forestry practices; storage of fertilizer; manure
and road salts; new construction; and sand and gravel mining/washing operations.
3.1.1 Spills And State 21E Sites
The degree of threat posed by spills and releases of oil or hazardous materials within
the Watershed is dependent on a number of factors including the pathway to the
surface water supply or tributaries, the date of the occurrence, the types and quantities
of materials involved, and the potential for migration to the surface water supply. The
DEP Matrix doesn’t have a specific rating for spills or state 21E sites since hazardous
waste sites are not land uses. Where appropriate, the DEP Matrix rating for the land
use that resulted in the spill or release is set forth in the discussion of the sites.
However, it is clear from the definition of a spills or state 21E site set forth above, that
these properties typically have the potential to pose a High risk to the surface water
supply. The types of contaminants associated with the spill or release are listed in the
corresponding sections.
Site Type of Land Use
DEP Land
Use Ranking
SWSPP
Ranking
Hingham Annex Military HIGH HIGH
Former Beechwood Dump Commercial, former Landfill HIGH HIGH
Former Burning Ground Military HIGH HIGH
Cohasset Heights Landfill Former Landfill HIGH HIGH
Former Clapp Landfill Municipal, former Landfill HIGH MODERATE
Untreated Stormwater Runoff Municipal HIGH HIGH
Storage of Fertilizer, Manure, Road Salt Commercial or Municipal HIGH MODERATE
Former Norfolk Conveyor Site Commercial and Industrial MODERATE HIGH
Septic Systems
Commercial, Industrial or
Residential MODERATE HIGH
* Sand & Gravel Mining/Washing Operations Commercial MODERATE LOW
Previous Spills Commercial or Residential LOW LOW
Massachusetts Highway Department State LOW LOW
Cohasset Water Treatment Plant Municipal LOW LOW
Cemeteries Municipal LOW LOW
* Land use (former) present in watershed area, but not in active operation.
DEP LAND USE MATRIX RANKING
TABLE 3-1
LILY POND & AARON RIVER RESERVOIR
SURFACE WATER SUPPLY PROTECTION PLAN FOR
Spills are locations where Immediate Response Actions (IRA), as defined in the
Massachusetts Contingency Plan6 (MCP), which sets forth the regulations governing the
reporting, assessment and remediation of hazardous waste sites in Massachusetts,
have been conducted to quickly mitigate soil and/or groundwater impacts caused by a
release of oil or hazardous material. Releases that require more comprehensive
response actions such as remediation are referred to as “state 21E sites”. Several
known spills and state 21E sites exist within the Watershed as indicated on Map 1b.
Some of these are undergoing response actions to assess and/or remediate
contamination and some have achieved a level of No Significant Risk (NSR) as defined
in the MCP. State 21E sites that have the greatest potential to adversely impact the
surface water supply are discussed below in more detail.
Hingham Training Annex Disposal Site – State 21E Site.
The Hingham Training Annex disposal site (the Hingham Annex) is located off Leavitt
Street adjacent to Wompatuck State Park and Whitney Woods Reservation in Hingham
near the northwestern extent of the Watershed. The Hingham Annex is approximately
1.75 miles west of Lily Pond and 1.65 miles northwest of the Aaron River Reservoir.
The closest tributary is Brass Kettle Brook located approximately 0.75 miles east of the
Hingham Annex. As discussed in Section 2.0, the extent of Brass Kettle Brook to the
west must be determined. If the perennial stream located west of the wetland is
hydrologically connected to Brass Kettle Brook, then the brook could extent west to the
Hingham Annex.
The Hingham Annex was established in 1941 as an ammunition depot by the U.S. Navy
and in 1971 was transferred to the U.S. Army, who utilized the site for Reserve training,
vehicle storage, and vehicle maintenance. The Department of the Army deactivated it
in 1982 and, according to a 1998 report7, the Army initiated assessment and remediation
activities at the site in 1985. Contaminants detected include total petroleum
hydrocarbons, metals, and semi-volatile organic compounds (SVOCs). The site has
been designated a Tier I disposal site pursuant to the MCP. Tier I disposal sites receive
the highest priority for assessment and clean up. Remedial activities at the Hingham
Annex have included removal of asbestos in buildings and excavation and removal of
underground storage tanks. Additional remediation, to include impacted soil removal, is
continuing as part of the efforts to close all the former ammunition bunkers at the site.
The DEP Matrix categorizes military facilities (both past and present) as High threats to
a surface water supply.
RECOMMENDATION 3.1 The Cohasset Board of Water Commissioners should
periodically review the progress of response actions conducted at the Hingham Annex
so that potential impacts to Brass Kettle Brook can be assessed.
6 310 CMR 40.0000 is titled the Massachusetts Contingency Plan.
7 Environmental Assessment, Hingham Cohasset (Hingham Training Annex, Massachusetts) Disposal
and Reuse, Department of the Army, October 1998.
RECOMMENDATION 3.2 The Cohasset Board of Water Commissioners should
periodically test Brass Kettle Brook for contaminants of concern detected at the
Hingham Annex with the potential to migrate to the brook via groundwater or surface
water flow.
Former Beechwood Dump – State 21E Site.
The dump is a former waste and munitions disposal area located in Wompatuck State
Park in Cohasset approximately 1,650 feet north of the Aaron River Reservoir and 0.65
miles southwest of Lily Pond. It was used as a munitions disposal area by the U.S Navy
from the time it was acquired in the early 1900’s to the time the property was sold to the
State in 1971. In a 1998 report, Stone and Webster8 document the discovery of
contaminated surficial and subsurface soils at the site. Analysis of groundwater
samples indicated that petroleum hydrocarbons were detected above MCP RCGW-1
reportable concentrations9 for groundwater. The site was classified Tier IB in October
2001 indicating further response actions are necessary to achieve a level of NSR.
The former Beechwood Dump is located relatively close to the wetlands associated with
the Aaron River. These wetlands are a likely groundwater discharge point for impacted
groundwater migrating from the former dump. The DEP Matrix categorizes landfills and
dumps as High threats to a surface water supply.
RECOMMENDATION 3.3 The Cohasset Board of Water Commissioners should
periodically review the progress of response actions conducted at the former
Beechwood Dump so that potential impacts to the Aaron River can be assessed.
RECOMMENDATION 3.4 The Cohasset Board of Water Commissioners should
periodically test the Aaron River for contaminants of concern detected at the former
Beechwood Dump with the potential to migrate to the river via groundwater or surface
water flow.
Former Norfolk Conveyor Site – State 21E Site.
The former Norfolk Conveyor site is located at 155 King Street in Cohasset. The 62-
acre property is situated on the eastern slope of Scituate Hill approximately 0.8 miles
northwest of Lily Pond and 1.65 miles north of the Aaron River Reservoir. Various
industrial and commercial activities have been conducted at the site including electrical
and radar equipment manufacture, DNA research and painting. Currently, the site is
used for storage and maintenance of dumpsters used for solid waste hauling and
electronic testing of receivers. Numerous oils or hazardous materials were stored and
used at the site in connection with the site activities. In 1983, a drum disposal area was
discovered at the property. Eight 55-gallon drums containing spent trichloroethylene
8 Site Assessment – Beechwood and Pleasant Street Dumps, Stone & Webster, July 2000.
9 Contaminant concentrations detected in soil or groundwater above the reportable concentrations set
forth in the MCP must be reported to the DEP.
(TCE) and associated contaminated soil were excavated and removed from the
property. An additional 30 empty drums, which may at the time of disposal have also
contained TCE were removed and disposed of as scrap metal. In 1984, volatile organic
compounds (VOCs) including TCE, benzene, methyl ethyl-ketone, toluene, acetone,
bromodichloromethane, carbon tetrachloride, chlorodibromoethane, chloroform, 1,2-
dichloroethane, 1,2-trans-dichloroethene, 1,1-dichloroethylene, 1,2-dichloropropane,
methylene chloride, and 1,1,1-trichloroethane were detected in surface water samples
collected from a former brook located at the intersection of Howes Road and Boulder
Lane approximately 1,300 feet south of the former Norfolk Conveyor site (referred to as
sample location C9 in a 1984 report by Camp Dresser & McKee10), and at another
former brook off Howes Road approximately 750 feet south/southwest of C9 (referred to
as sample location C10). At one time prior to the development of the CHL Landfill,
these streams drained extensive wetlands south of Scituate Hill and flowed into Brass
Kettle Brook. The 1984 CDM report described the geology of the wetlands as areas of
greatest soil thickness consisting of deposits of gravel, sand and/or silts. The USGS
indicates that most of the wetland areas of Brass Kettle Brook and its tributaries are
underlain by predominantly fine to coarse sand and gravel with relatively high hydraulic
conductivities of 150 to 475 feet per day, and some thin beds of fine to coarse sands
and silt.
In 1984, VOCs were also detected in groundwater monitoring wells installed in and
around the drum disposal area (referred to as monitoring wells C3, C5 and C6).
Groundwater flow from the former Norfolk Conveyor site is expected to flow south
towards Lily Pond via the depositional sands associated with past or present
wetlands/stream systems.
In 1993, the DEP reviewed the site information and determined the drum disposal
release required “No Further Action”, although the Site remains on the EPA’s
Comprehensive Environmental Response, Compensation and Liability Information
System (“CERCLIS”) list. CERCLIS is the official repository for site and non-site
specific Superfund data in support of the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA). It contains information on hazardous waste
site assessment and remediation from 1983 to the present. CERCLIS information is
used to report official Superfund accomplishments to Congress and the public, assist
EPA Regional and Headquarters managers in evaluating the status and progress of site
cleanup actions, track Superfund Comprehensive Accomplishments Plans (SCAP), and
communicate planned activities and budgets.
According to a February 1, 2001 report by HML Associates, elevated TCE and other
VOCs were detected in January of 2001 above the MCP Method 1 GW-1 Groundwater
Standards in monitoring wells C3, C5 and C6, and in newly installed wells at the site.
On behalf of the Cohasset Water Commission, Norfolk Ram Group has been monitoring
bedrock wells located south of the Norfolk Conveyor site on a quarterly basis since
10 Hydrogeological and Water Quality Study of the Watersheds Tributary to Lily Pond and Great Swamp
in the Area of Scituate Hill, Camp Dresser & McKee, November 1984.
2000. The analyses included VOCs via EPA Method 8260. To date, no VOCs included
in the EPA Method 8260 list have been detected above the Massachusetts Maximum
Contaminant Levels (MMCL) or the Massachusetts Secondary Maximum Contaminant
Levels (SMCL) for drinking water. The MMCLs are legally enforceable standards that
apply to public water systems in Massachusetts that are based upon known or
suspected health concerns associated with ingestion of the contaminants.
Contaminants that exceed the MMCLs must be removed from drinking water prior to
distribution. The SMCLs are non-mandatory standards established as guidelines to
assist public water systems manage their drinking water for aesthetic considerations
such as taste, color and odor. These contaminants are not considered to pose a risk to
human health at the SMCL.
The DEP Matrix categorizes paint shops and electronics/electrical manufacturers as
Moderate threats to a surface water supply. Petroleum and chemical storage is
considered a High threat and research laboratories are considered a Low threat. Based
upon the new information contained in the February 1, 2001 HML Associates report, the
former Norfolk Conveyor site is considered a High threat to the surface water supply.
RECOMMENDATION 3.5 The Cohasset Board of Water Commissioners should
continue to monitor the bedrocks wells on a quarterly basis, and periodically review the
progress of response actions conducted at the former Norfolk Conveyor site so that
potential impacts to Lily Pond can be assessed.
RECOMMENDATION 3.6 The Cohasset Board of Water Commissioners should also
consider evaluating the feasibility of installing overburden-monitoring wells in the
depositional sands and gravels of the former or existing wetlands located between the
former Norfolk Conveyor site and Lily Pond. The geology of these wetlands are areas
of greatest soil thickness consisting of deposits of gravel, sand and/or silts with
relatively high hydraulic conductivities, and could potentially serve as a pathway for
impacted groundwater to Lily Pond.
Former Burning Ground – State 21E Site.
The former “Burning Ground” is a 4-acre area located in the southeast section of
Wompatuck State Park approximately 250 feet north of Holly Pond and the Aaron River
and approximately 400 feet south of the Wompatuck State Park campground area.
From 1945 to the late 1960’s the U.S. Navy and government contractors used the site to
burn ordnances. Soil, groundwater, surface water and sediment at the site were
evaluated as part of a Phase I Initial Site Investigation conducted in the late fall of 2000
by Arthur D. Little for the U.S. Army Corps of Engineers. The investigation identified
two areas where concentrations of contaminants exceeded the MCP reportable
concentrations for RCS-1 soils. Polycyclical aromatic hydrocarbons were found in
surface soils in one limited area of the Site (Burning Ground No. 1) and antimony,
barium, beryllium, copper, lead, zinc, diethylphalate, RDX, and TNT were found mostly
in surficial soils in another limited area of the Site (Burning Ground No. 2). Volatile
petroleum hydrocarbons (VPH) and explosive compounds were detected in
groundwater at the Site, but at concentrations below MCP RCGW-1 reportable
concentrations. Groundwater at the site flows to the southeast, towards the Aaron
River. Some migration of contaminants is evident since low concentrations of
polycyclical aromatic hydrocarbons and explosive compounds were detected in
sediment and surface water samples collected from a drainage culvert at the southern
portion of the site, and low concentrations of explosive compounds were detected in a
groundwater sample collected from a monitoring well at the southern portion of the site.
No contaminants were detected in sediment and surface water samples collected from
the Aaron River or Holly Pond. The Site has been classified Tier IC, and a Scope of
Work has been submitted to DEP for a Phase II Comprehensive Site Assessment,
which will determine the full extent of contamination.
The DEP Matrix categorizes landfills and dumps and military facilities (past and present)
as High threats to a surface water supply.
RECOMMENDATION 3.7 The Cohasset Board of Water Commissioners should
periodically review the progress of the response actions conducted at the former
Burning Ground so that potential impacts to Aaron River or Holly Pond can be
assessed.
RECOMMENDATION 3.8 The Cohasset Board of Water Commissioners should
periodically test the Aaron River at the south end of the reservoir for the contaminants of
concern detected at the Burning Ground with the potential to migrate to the river via
groundwater or surface water.
35 Arrowwood Street, Cohasset – Spills Site.
On April 12, 2002, a release of approximately 250 gallons of No. 2 fuel oil leaked from
an above ground storage tank at 35 Arrowwood Street in Cohasset [designated as Spill
1 on Map 1b]. The spill saturated the ground adjacent to the house and proceeded to
run down the street and into a stormwater system. The Cohasset Fire Department
responded to the call by placing absorbent booms before catch basins at the lower end
of the street and cleaning the stormwater system. Due to the immediate nature of the
response, this spill site is considered a Low potential threat to the surface water supply.
Beechwood Street, Cohasset – Spills Site.
In July of 1999, approximately 20 gallons of an unknown chemical was released from a
transformer on Beechwood Street in Cohasset [designated as Spill 2 on Map 1b]. An
IRA was conducted and the contamination was reduced to background levels. It was
concluded that the site achieved a level of NSR, and a Response Action Outcome
(RAO) Statement was submitted to DEP in September 1999. Due to the immediate
nature of the response and the RAO, this spill site is considered a Low potential threat
to the surface water supply.
Schofield Road, Cohasset – Spills Site.
In May of 1998, a release of No. 2 fuel oil occurred from an underground storage tank at
a residence located on Schofield Road in Cohasset [designated as Spill 3 on Map 1b].
An IRA was conducted and the contamination was reduced to below MCP Clean-up
Standards. It was concluded that the site achieved a level of NSR, and a RAO
Statement was submitted to DEP in March 1998. Due to the immediate nature of the
response and the RAO, this spill site is considered a Low potential threat to the surface
water supply.
422 King Street, Cohasset – Spills Site.
In October 1993, approximately 30 gallons of non-PCB-containing transformer oil was
released when a vehicle hit a telephone pole in front of 422 King Street in Cohasset
[designated as Spill 4 on Map 1b]. It was concluded that the site achieved a level of
NSR, and a RAO Statement was submitted to DEP. Due to the age of the occurrence,
the immediate nature of the response and the RAO this spill site is considered a Low
threat to the surface water supply.
King Street, Cohasset – Spills Site.
In May of 1989, a release of gasoline from an underground storage tank located on King
Street in Cohasset [designated as Spill 5 on Map 1b] was reported to DEP. Between
100 and 250 cubic yards of contaminated soil was excavated. The outcome of the
release is not known. Due to the age of the occurrence, and the volume of impacted
soil removed, this spill site is considered a Low potential threat to the surface water
supply.
Flint Rock Road, Cohasset – Spills Site.
In June of 1988, not more than 10 gallons of herbicide was released from a tanker truck
was reported on Flint Lock Ridge Road in Cohasset [designated as Spill 6 on Map 1b].
The outcome of the release is not known. Due to the age of the occurrence, this spill
site is considered a Low potential threat to the surface water supply.
3.1.2 Waste Disposal Facilities
The DEP Matrix categorizes landfills and dumps as High threats to a surface water
supply. Two waste disposal facilities are located within the Watershed, the CHL Landfill
and the former Clapp Landfill. Much more is known about the CHL Landfill, and it is
considered a much greater threat to the surface water supply than the former Clapp
Landfill. A brief description of these sites follows.
Cohasset Heights Landfill.
The CHL Landfill is an inactive, partially capped, solid waste landfill located on the
southwest side of Scituate Hill in Cohasset approximately 1 mile northwest of Lily Pond.
It occupies approximately 26 acres, and has generally been used for the disposition of
construction and demolition waste and municipal solid waste. Approximately 40 percent
of the CHL Landfill is located within the Watershed. This portion of the landfill is the
oldest and was developed in a former gravel pit and wetland areas. Most of this portion
of the landfill is unlined. The landfill stopped receiving waste in July of 1998. Some of
the landfill has been capped but portions remain uncapped in several areas.
Contaminants typically associated with landfill leachate include VOCs, SVOCs,
petroleum hydrocarbons, polychlorinated byphenyls (PCBs), metals, and nitrate.
Landfill leachate contaminants have been detected in samples collected within the
Watershed from downgradient monitoring wells, surface water, and sediments. The
1984 CDM report states that there was evidence indicating that contaminants from the
CHL leachate were reaching Lily Pond. An October 1998 report11 by Norfolk
Environmental, Inc. concluded the following:
x VOCs have historically been detected in groundwater samples collected
from monitoring wells located in Whitney Woods up to 1,300 feet from the
landfill;
x 1-4-dichlorobenzene has been consistently detected at concentrations
above the DEP’s RCGW-1 groundwater reportable concentration in
monitoring wells located on the western side of the landfill bordering the
wetlands;
x The migration of these and other landfill-related compounds may pose a
threat to the wetlands in violation of the Massachusetts Surface Water
Quality Standards in connection with the Outstanding Resource Water,
Lily Pond.
x Suspected subsurface groundwater migration pathways through bedrock
fractures have been documented and field-verified via geophysical very
low frequency (VLF) radio wave detection. The identified fractures run
from the western side of the landfill southerly towards Brass Kettle Brook;
and
x Sediment samples from Brass Kettle Brook contain lead at concentrations
approaching the DEP’s S-1 reportable concentration. Lead has been
detected at concentrations above the DEP’s Ambient Water Quality
Standards in surface water collected from Brass Kettle Brook and an
unnamed tributary whose source is at the base of the landfill. These lead
detections suggest migration of lead from the landfill.
On behalf of the Cohasset Board of Water Commissioner, on August 31, 2000 Norfolk
Environmental, Inc. filed a Request for Determination of Applicability12 with the Cohasset
Conservation Commission. The RDA suggested that the CHL Landfill appears to be in
violation of the Cohasset Wetlands Bylaw prohibition against alteration of a resource
area. The RDA proposed that a Leachate Control Remedy consisting of a leachate
collection trench be required to prevent CHL from discharging leachate offsite into the
11 Report on Potential Contaminant Migration From Cohasset Landfill to Lily Pond, Norfolk Environmental,
Inc., October 8, 1998.
12 Request for Determination of Applicability – Concerning the Discharge of Leachate from Cohasset
Heights Ltd. Landfill to the Lily Pond Water Supply Watershed, Norfolk Environmental, Inc., August 31,
2000.
Watershed. The Commission closed the hearing on November 30 and voted to require
the CHL Landfill to prepare a Notice of Intent (NOI) to respond to the Water
Commission’s RDA. The Conservation Commission issued a positive Determination of
Applicability on December 18, 2000, that directed CHL to prepare the NOI within 90
days of that order.
In 2000, Norfolk Environmental, Inc., on behalf of the Cohasset Board of Water
Commissioners, installed three bedrock monitoring wells as indicated on the
accompanying maps. These wells intercept the bedrock fractures identified by the VLF
geophysical survey, and are sampled on a quarterly basis for volatile organic
compounds, chemical oxygen demand, chloride, and the five “landfill” metals (antimony,
arsenic, cadmium, chromium, and lead). To date, sampling of these bedrock wells has
not detected contaminant migration through the bedrock fractures.
In response to the positive RDA, CHL submitted a NOI on January 23, 2002 that
proposed to conduct water quality protection measures and assessment work. The
activities proposed in the NOI included:
1. Reducing the volume of leachate that is currently generated by the existence of
the Landfill (based on capping and final landfill closure);
2. Conducting further water quality characterizations work to determine potential
impacts to the Watershed; and,
3. Constructing improvements to the existing leachate and underdrain collecting
system, commensurate with conditions that result from actions (1) and (2) above.
In issuing a decision on this NOI, the Conservation Commission issued an Order of
Conditions on February 8, 2002 that required CHL to:
x Sample groundwater from each CDM well (or its replacement) once during
high water table conditions and once during low water table conditions,
and sample surface water during high water conditions at groundwater
monitoring locations along the lower wetlands; and
x Submit a report of the results of the sampling program that included an
analysis of the potential impact of the landfill on the water quality of the
lower wetlands, as well as recommendations for any additional monitoring
or remediation that may be necessary.
The Conservation Commission also approved the following activities: reduce the
volume of leachate that is currently generated by the existence of the landfill through
final capping, closure and associated activities; conduct additional water quality
characterization work to determine potential impacts to the watershed; and construct
improvements to the existing leachate and underdrain collection systems, to the extent
necessary after landfill closure.
The potential exists for transfer of landfill contaminants to the surface water supply via
surface water flow, and groundwater flow through overburden and identified and
unidentified bedrock fractures. The DEP Matrix categorizes landfills and dumps as High
threats to a surface water supply.
RECOMMENDATION 3.9 The Cohasset Board of Water Commissioners should
continue to monitor the bedrocks wells on a quarterly basis, until the SWSPP is revisited
(after three years) at which time the need to monitor can be reevaluated, and
periodically review the progress of response actions conducted at the CHL Landfill so
that potential impacts to Lily Pond can be assessed.
RECOMMENDATION 3.10 The Cohasset Board of Water Commissioners should
consider evaluating the feasibility of installing overburden-monitoring wells in the
depositional sands and gravels of the former or existing wetlands located between the
CHL Landfill and Lily Pond. The geology of these wetlands are areas of greatest soil
thickness consisting of deposits of gravel, sand and/or silts with relatively high hydraulic
conductivities, and could potentially serve as a pathway for impacted groundwater to
Lily Pond.
Former Clapp Landfill.
The former Clapp Landfill is located within the Watershed, southeast of the Aaron River
Reservoir, in Scituate. The site is a former solid waste disposal area that was closed in
1960 and at some point capped. According to Scituate officials, an environmental
assessment performed near the site found high levels of nitrate and other constituents
indicating that these contaminants may be leaching from the landfill. The landfill was
recapped in July 2001. The soil and groundwater has not been tested for contaminants
since the recapping.
The DEP Matrix categorizes landfills and dumps as High threats to a surface water
supply. The threat posed by the former Clapp Landfill is mitigated however by the long
pathway to Lily Pond, the closure of the landfill in 1960 and the recapping in 2001. This
assessment may change pending the outcome of future assessment activities.
RECOMMENDATION 3.11 The Cohasset Board of Water Commissioners should
periodically review the progress of the response actions conducted at the former Clapp
Landfill so that potential impacts to Aaron River Reservoir can be assessed.
RECOMMENDATION 3.12 The Cohasset Board of Water Commissioners should
periodically test the Aaron River at the south end of the reservoir for the contaminants of
concern detected at the former Clapp Landfill with the potential to migrate to the river
via groundwater or surface water.
3.1.3 Use and Storage of Hazardous Materials
The DEP Matrix categorizes the use and storage of hazardous materials as High threats
to a surface water supply. All of the Watershed towns have bylaws restricting the use
and storage of hazardous materials within their Water Resources Protection Districts,
which are discussed below in more detail. Combined, these districts cover a large
portion of the Watershed as indicated on Figure 2. There are no commercial properties
within the Watershed that are permitted as RCRA generators of hazardous materials.
The threat to the surface water supply is mitigated by the fact that, in general, use and
storage of hazardous materials is not prevalent within the Watershed.
RECOMMENDATION 3.13 The Watershed communities in cooperation with the
Cohasset Board of Water Commissioners should continue to implement and periodically
review and update where appropriate their Water Resources Protection Districts bylaws.
The Cohasset Board of Water Commissioners should request the opportunity to review
the community bylaws or proposed changes and make recommendations towards
furthering the protection of the surface water supply.
3.1.4 Untreated Stormwater Runoff
Surface runoff of stormwater, which includes precipitation and snowmelt, can be a
significant potential threat to wetlands and the surface water supply. This runoff can
typically contain many pollutants that have accumulated on the paved surfaces such as
gasoline, used motor oil, antifreeze fluids, lead, and asbestos from automobiles,
microbial pathogens, deicing chemicals, nutrients such as nitrogen as well as airborne
particulate deposition from automobile exhaust and industrial or commercial operations.
Lily Pond’s trophic state has recently been evaluated as eutrophic bordering on hyper-
eutrophic in work conducted as part of this SWSPP13. Trophic states are classified as
oligotrophic (having no or insignificant nutrient levels), or mesotrophic (having an
intermediate level of nutrients), or eutrophic (nutrient-enriched). Eutrophic conditions
occur when sufficient nutrients such as nitrogen, in the form of nitrates, and phosphorus
in the form of phosphates, are available to result in uncontrolled plant (algae) growth
with detrimental effects to the water quality. A similar condition exists for the Aaron
River Reservoir. In addition to stimulating excess plant growth, nitrogen in the form of
nitrate has been identified as a public health risk. Specifically elevated levels14 of nitrate
in drinking water can cause methemoglobinemia (or blue baby syndrome) in infants.
Other potential health affects include cancer, disruption of thyroid function, birth defects
and miscarriages. One of the main contributors of nitrates and phosphorous to the
surface water supply is untreated stormwater. The DEP Matrix categorizes stormwater
drains/detention basins as High threats to a surface water supply. Of all the threats
discussed in this SWSPP, eutrophication may be the single greatest concern due to the
direct evidence of its occurrence.
For the past several years sodium has been detected in the municipal water supply at
concentrations above the DEP’s Office of Research and Standards Guideline (ORSG)
of 20 parts per million. This is most likely a direct result of using deicing chemicals
containing sodium and chloride along roads whose drainage basins are tributary to Lily
Pond or its tributaries.
Many portions of the Watershed have “country drainage15”, where stormwater is allowed
to naturally run off paved areas onto the sides of the roads, and other areas that have
catch basins that direct the runoff to surface water bodies or allow it to leach into the
soil. Of the three methods, directing the runoff into surface water bodies provides the
least amount of filtration or treatment, and therefore, is most detrimental to the water
quality.
13 Evaluation of Trophic Status of Lily Pond, Cohasset, Massachusetts, Conrad Leszkiewicz, 2001,
subcontract work as part of this SWSPP report.
14 The Massachusetts Maximum Contamination Levels for nitrate in drinking water is 10mg/l.
15 Country drainage refers to the practice of having earth-lined ditches or grassy swales running parallel
to the road to collect and convey stormwater runoff.
Cohasset. There are several areas within the Watershed in Cohasset where the
surface water supply is susceptible to pollution from untreated stormwater runoff. In
particular, Lily Pond is susceptible along parts of King Street, Pond Street, and parts of
Route 3A near Peppermint Brook. The Aaron River Reservoir is susceptible to
stormwater runoff from parts of Doane Street, parts of Beechwood Street near Doane
Street, Arrowwood Street, and parts of Aaron River Road. Norfolk Ram Group as
consultant to the Cohasset Water Commission prepared a preliminary inventory of
Stormwater drainage systems immediately tributary to Lily Pond. This preliminary
survey was completed on October 2001. (See memo in Appendix B).
In 2000, the Cohasset Board of Health developed a management plan16 to address
stormwater runoff. The plan calls for mapping of existing drain systems using GIS,
evaluating and ranking the threat pose by each system, and identifying and
implementing Best Management Practices to mitigate impacts to the surface water
supply.
Hingham. Stormwater runoff in Hingham presents no significant impact to the surface
water supply since most Hingham roads within the Watershed are located in
Wompatuck State Park and are not heavily traveled.
Norwell. Stormwater drainage in Norwell typically consists of country drainage on their
older roads, with newer roads designed with catch basins. Parts of Mount Hope Street
and Mt. Blue Street are within the Zone A.
Scituate. In Scituate, parts of Thomas Clapp Road, Summer and Cedar Streets are
located within the Zone A. Stormwater runoff from these roads could directly impact the
water quality of the Aaron River Reservoir or its tributaries. In addition, stormwater
easily overruns drainage systems and banks of perennial and intermittent streams that
in turn flow untreated directly into the surface water supply.
The Towns of Cohasset, Hingham, Norwell, and Scituate are required to comply with
Phase II of the EPA’s National Pollution Discharge Elimination System17 (NPDES)
Stormwater Program by 2003. This program requires NPDES permit coverage for
stormwater discharges from municipal separate storm sewer systems and construction
activities disturbing between 1 and 5 acres of land. Application for NPDES permit
coverage is due by March 10, 2003.
RECOMMENDATION 3.14 It is reported the Towns of Norwell and Scituate are
currently developing stormwater management plans similar to Cohasset’s. Best
Management Practices should be identified and implemented immediately for the
sections of road identified as posing a significant threat to the surface water supply. At
a minimum, no-salt zones should be designated along the sections of roads with
16 Cohasset Stormwater Management Plan and Control Strategies, Town of Cohasset Board of Health,
August 2000.
17 National Pollutant Discharge Elimination System, an EPA permit program authorized under the Federal
Clean Water Act.
drainage basins that discharge directly to the surface water supply. Also, the Planning
Board for Cohasset and the other watershed communities should codify in their rules
and regulations stormwater controls as part of the approval process for site plans,
subdivisions and other proposed creation of impervious areas. At a minimum these
regulations should require compliance with the DEPs Best Management Practices set
forth in their Stormwater Management Policy.
RECOMMENDATION 3.15 The Watershed communities should comply with the DEP’s
Phase II Stormwater Management Program by the required deadline in 2003. The
Cohasset Board of Water Commissioners should request the opportunity to follow and
comment on the communities’ progress in preparing these programs.
3.1.5 Septic Systems
On-site disposal of household septage via septic systems or cesspools can contribute
nutrients such as nitrite, nitrate and ammonia and phosphorus (from laundry detergent),
as well as, household chemicals and pathogens to the surface water supply.
Phosphorus is typically the limiting nutrient in freshwater to the uncontrolled algae
growth that leads to eutrophication. The DEP Matrix categorizes septic
systems/cesspools as Moderate threats to a surface water supply. Septic systems
located within 400 feet the surface water supply or tributaries, can pose a higher threat
since phosphorus can travel this distance in groundwater.
Table 3-2 below, tabulates the location of known septic systems within the Watershed
based upon the year the systems were installed and their location within Zone A, B or
C. Systems designated pre-1978 were installed prior to Title 518, which was
promulgated in 1978. The original intent of Title 5 was to establish hydraulic controls for
the on-site disposal of sanitary sewage. It mandated engineering solutions for
subsurface disposal of sanitary sewage thus preventing potential human exposure to
sewage discharged to the ground surface. In 1995 changes to Title 5 were
implemented that enhanced the passive treatment of sewage in the subsurface. The
new Title 5 Standards require leaching facilities to be installed within the aerated zone
of the soil to increase aerobic biological degradation of organic compounds. This was
accomplished by requiring 4 to 5 feet of separation from “probable high groundwater”
(which previously had not been required). The new Title 5 standards also provide for
advanced septic systems that achieve much greater organic compound degradation
and nitrogen removal. These systems are typically required in some environmentally
sensitive areas (e.g., nitrogen sensitive areas); and in areas where individual system
flows exceed 2,000 gpd or in areas where proper separation from groundwater or
separation from bedrock cannot be achieved with standard system upgrades.
18 310 CMR 15.000 The State Environmental Code, Title 5.
There are approximately 42 septic systems within the Zone A of the Watershed, 26 of
which are located in Cohasset, 10 in Scituate (along reservoir east side), and 6 in
Norwell. Almost 90% of these septic systems are older systems that were constructed
prior to the implementation of the 1995 Title 5 Standards and, therefore, may present a
more significant risk to water quality. Six of the septic systems within the Zone A were
constructed pre-1978, and some of these include cesspools. Cohasset has adopted a
wastewater management plan19, which is a voluntary plan that Cohasset citizens may
join to receive town-managed services for their residential septic systems if they pass a
Title 5 Inspection. The plan offers 20-year loans to homeowners to repair/upgrade their
septic systems should they fail at some future date. Other services to members include
Title 5 Inspections, annual evaluations, tank pumping (typically, every three years),
maintenance, repair, and upgrades.
Cohasset. Of particular concern are the 24 older systems within the Zone A in
Cohasset since older systems do not provide the level of treatment of the newer Title 5
systems. Since 2000, the Town of Cohasset has extended its sewer system into the
19 Cohasset Comprehensive On-Site Wastewater Management Plan, Town of Cohasset Board of Health,
August 2000.
Pre-1978 1978-94 1995-Present
1995 (advanced
septic) - Present Totals
Cohasset Zone A 5192 0 26
Cohasset Zone B 5 145 30 3 183
Cohasset Zone C 5 148 28 3 184
Hingham Zone A 00000
Hingham Zone B 00000
Hingham Zone C 02002
Norwell Zone A 14106
Norwell Zone B 542 0 11
Norwell Zone C 583 0 16
Scituate Zone A 0100 0 10
Scituate Zone B 63713 0 56
Scituate Zone C 65113 0 70
TOTALS 38 428 92 6 564
NOTE: For Norwell, data available is only for those parcels within or adjacent to Zone A.
TABLE 3-2
NUMBER AND TYPE OF SEPTIC SYSTEMS BY ZONE
SURFACE WATER SUPPLY PROTECTION PLAN
LILY POND & AARON RIVER RESERVOIR
high-density areas north and west of Lily Pond. This has removed approximately 47
septic systems from the Zone A, 142 septic systems from the Zone B, and an additional
567 septic systems from the Zone C of the Watershed in Cohasset. The removal of
these septic systems will reduce the nutrient loading to Lily Pond via Peppermint Brook,
where previous water quality studies had found significant levels of fecal coliform
bacteria and nitrate. Another 183 septic systems remain in the Zone B (18% installed
under older Title 5 Standards) and 184 remain in the Zone C (17% installed under older
Title 5 Standards) in Cohasset.
Hingham. There are only two septic systems in Hingham known to be within the
Watershed and these are located along the northwest edge of the Watershed on Leavitt
Street approximately 1,000 feet north of Brass Kettle Brook and 1.6 miles northwest of
Lily Pond. Both of these septic systems were installed in 1983 under the 1978 Title 5
Standards and do not pose a significant threat because of their distances from the
surface water supply or tributaries.
Norwell. Norwell has approximately 6 septic systems within the Zone A, located near
Mt. Blue Street and Mount Hope Street near susceptible surface water bodies such as
Bound Brook Pond and its outflow stream. Eleven septic systems are located within the
Zone B in Norwell and 16 septic systems are located in the Zone C. While the number
of Norwell septic systems is small and does not suggest a significant potential threat,
the age of these systems raises some concerns. One-third of the systems were
installed prior to 1978.
Scituate. Septic systems at a new development located off Thomas Clapp Road in
Scituate present a significant potential threat of contamination to the Aaron River
Reservoir. The entire development is located within the Watershed, and consists of 3
roadways with a total of 17 home sites. A portion of the site directly abuts the Town of
Cohasset, and in particular, two lots abut the Scituate portion of the Aaron River
Reservoir. Other areas of the development abut bordering vegetative wetlands on all
sides. To date 10 houses have been constructed with septic systems designed under
the 1978 Title 5 Standards. The leaching facilities for these 10 septic systems are
clustered together due to the limited area of suitable soils, and eight of the systems are
within approximately 200 feet of the Aaron River Reservoir. These septic systems are a
significant concern because of the significant increase in the concentration of septic
effluent in an area of transmissive soils so close to the Aaron River Reservoir, and the
fact that they do not comply with the more stringent 1995 Title 5 Standards.
In Scituate, a new residential development is planned with a potential of 250 houses.
The area of the development is within the Watershed of the extension of the South
Swamp tributary and associated wetlands that originate north of Clapp Road.
Development of this area could pose a threat to the surface water supply if controls are
not in place.
RECOMMENDATION 3.16 As stated in Recommendation 2.1, the Town of Scituate
should locate/map and recognize for proper Title 5 setback requirements, filling and
dredging restrictions, Zone A prohibitions, and, if applicable Rivers Act buffer
requirements the extension of the South Swamp tributary to the Aaron River Reservoir
identified by the First Herring Brook Watershed Initiative.
In Scituate, there are approximately 50 septic systems located southeast of the Aaron
River Reservoir within the Zone B. Almost 40% of these septic systems were
constructed or upgraded to meet the 1995 Title 5 Standards. Only 4% of the systems
were installed prior to the 1978 Title 5 Standards. Also, as noted above, there are ten
(10) clustered septic systems located within the Zone A in Scituate, built according to
pre-1995 standards.
RECOMMENDATION 3.17 The Watershed communities should develop and
implement Comprehensive On-Site Wastewater Management Plans. The occupants of
residences within 400 feet of the surface water supply or tributaries should be instructed
as to the detrimental effect of antiquated septic systems, disposal of chemicals via sinks
or toilets and the benefits of using laundry detergents that do not contain phosphates.
The towns should consider adopting regulations possibly designating Septic System
Management Districts where periodic inspections of septic systems within the Zone A
are mandated.
RECOMMENDATION 3.18 The towns of Cohasset and Scituate should extend the
municipal sewer into areas where residences with on-site septic systems are located
within the Zone A.
RECOMMENDATION 3.19 The Town of Cohasset and the other watershed
communities should adopt zoning and non-zoning controls within the Zone A pursuant
to 310 CMR 22.00, the Drinking Water Regulations. In Cohasset, for proposed zoning
changes, the Cohasset Board of Water Commissioners should enlist the support of the
Zoning Advisory Committee, which is a sub-committee of the Planning Board.
3.1.6 State and Municipal Land and Facilities
The main types of state and municipal land and facilities located within the Watershed
are discussed below.
Massachusetts Highway Department.
A Massachusetts Highway Department (“MHD”) facility is located on Scituate Hill in
Cohasset, partially within the Zone C. The facility stores road salt, however, no vehicle
washing, or repair are conducted. A history of prior contamination at the MHD facility
has been well documented in historic reports submitted to the DEP. Sodium and
chloride are the primary contaminants of concern caused by the leaching of uncovered
deicing chemicals. Assessment work conducted as part of an investigation of the CHL
Landfill indicates high concentrations of sodium and chloride in groundwater collected
downgradient of the MHD facility in the direction of Lily Pond. The assessment work
conducted at the CHL Landfill is important since groundwater sampling and analysis has
been discontinued at the MHD facility. As discussed above, sodium has been detected
in the municipal water supply at the water treatment plant above the state ORSG
concentration. MHD has recently completed construction of a totally enclosed salt
storage facility to prevent leaching of sodium and chloride into groundwater caused by
exposure to the elements. The DEP Matrix categorizes road and maintenance depots
as Low threats to a surface water supply. Although historically, this MDH facility
represented a High threat, the current improved facility should be consistent with the
DEP Matrix as a Low threat in the future.
RECOMMENDATION 3.20 The Cohasset Board of Water Commissioners should
periodically review the progress of the response actions conducted at the CHL Landfill
so that potential impacts to Lily Pond can be assessed.
RECOMMENDATION 3.21 The Cohasset Board of Water Commissioners should
implement the surface water monitoring as indicated in the long-term sampling plan set
forth in Section 4.0.
Cohasset Water Treatment Plant.
The Cohasset water treatment plant is located within the Zone A, at the north end of Lily
Pond. The Plant has a design capacity of 3.0 million gallons per day (mgd) and a
current capacity of 2.5 mgd, and uses coagulation and flocculation processes (to help
reduce turbidity), filtration, the addition of lime (to adjust pH) and the addition of chlorine
and fluoride to the finished water that enters the distribution system. Approximately
12,000 pounds of chlorine are stored on-site. The water treatment plant has no floor
drains and all chemicals are stored inside the building within secondary containment.
On March 19, 2002, the water treatment plant was connected to the municipal sewer
system for discharge and disposal of sanitary waste. Sludge from the system is
transferred to two concrete-lined sludge-settling lagoons, located on-site. The facility
has a permit to discharge its supernatant effluent from the sludge settling lagoons to Lily
Pond under a federal National Pollutant Discharge Elimination System (NPDES) permit.
After drying, the sludge is currently stored on-site. The DEP Matrix categorizes water
treatment sludge lagoons as Low threats to a surface water supply.
RECOMMENDATION 3.22 The Cohasset Board of Water Commissioners should
evaluate the potential for off-site disposal of the treatment sludge pursuant to 310 CMR
32.00, the Land Application of Sludge and Septage regulation.
Cemeteries.
The Matrix categorizes cemeteries as Low threats to a surface water supply. However,
cemeteries can be sources of groundwater contamination from chemicals associated
with embalming such as arsenic, atrazine, 2,4-D, methoxychlor, glyphosate, simazine,
carbaryl, dicamba, picloram, diazinon, pentachlorophenol, phenol, nitrate, and nitrite. In
addition, pesticide, herbicide and fertilizer applications associated with lawn
maintenance can load stormwater runoff with detrimental contaminants that could find
their way into the surface water supply.
The Beechwood Cemetery located on Beechwood Street in Cohasset is approximately
680 feet northeast of the Aaron River Reservoir, 260 feet from the Aaron River and 65
feet from the Zone A along the river.
RECOMMENDATION 3.23 The Cohasset Board of Water Commissioners in
partnership with Boards of Health in the Watershed communities should develop and
implement a Lawn Care Management Program for areas within the Zone A and all town-
owned properties. The plan should define areas where the application of lawn care
chemicals is prohibited such as within 200 feet of the surface water supply or tributaries,
and establish recommended application procedures and frequencies for areas within
the Zone A and Zone B.
The Mount Hope cemetery is located within the Zone C in Scituate more that 600 feet
from the Zone B, and is not considered a significant threat to the surface water supply.
Town Parks.
The Town of Cohasset also owns Beechwood Park, a 2.78-acre park located across
Beechwood Street from the Beechwood Cemetery. The park is used as a baseball field
and for other recreational activities, and is not considered a significant threat to the
surface water supply; however, it should be included in the Lawn Care Management
Program recommended above.
There are no other state or municipal land and facilities within the Watershed in
Hingham, Norwell, or Scituate.
3.1.7 Industrial Wastewater Discharge
The DEP Matrix categorizes NPDES locations as High threats to a surface water
supply. Only one NPDES permit for discharge of wastewater currently exists for the
Cohasset water treatment plant for the discharge of the supernatant from their sludge
settling lagoons into Lily Pond.
The CHL Landfill had a NPDES permit for discharging stormwater from a landfill area to
an area outside of the Watershed, however, this permit has expired; and, a permit for
stormwater discharge to the Lily Pond Watershed has never been issued as required.
RECOMMENDATION 3.24 The Cohasset Board of Water Commissioners should
demand that the EPA order the CHL Landfill operator to obtain and keep current a
NPDES permit for the discharge of its landfill stormwater into the Lily Pond Watershed.
3.1.8 Public and Private Recreation
The DEP Matrix does not categorize public and private recreation areas. Such areas
within the Watershed include the Wompatuck State Park and Trustee of Reservations
land, both located primarily in Hingham, and three small playing fields located in
Cohasset. Wompatuck State Park and the Trustee of Reservations land within the
Watershed are Protected Open and Recreational Space, covering approximately 2,700
acres or 40% of the Watershed.
Wompatuck State Park is an approximate 3,600-acre parcel of land primarily located in
Hingham but extending partially into Cohasset, Norwell and Scituate. It has been
owned, operated and maintained by the Massachusetts Department of Environmental
Management (DEM) since the land was bought from the United States Navy in 1974.
Approximately 2,300 acres of Wompatuck State Park lie within the Watershed and the
land consists primarily of upland forest and wetlands. The Park has a camping area
with a capacity of 440 campsites, two paved parking lots, a wildlife management area,
and 1.3 miles of paved bicycle paths.
The Trustee of Reservations, a member-supported, non-profit conservation organization
owns Whitney and Thayer Woods (the Woods), located in Cohasset and Hingham.
Approximately 380 acres of the Woods are located within the Watershed consisting of
upland forest. Walking along paths through the Woods is the main recreational activity
located within the Watershed boundary. A pervious parking lot is located off Route 3A
in Cohasset for vehicle parking.
3.1.9 Electric Transmission Line Right-of-Way
Massachusetts Electric Company transmission lines enter the Watershed from the
north, travel through Cohasset and Hingham, and leave the Watershed through Scituate
at the west side of the Watershed. National Grid USA maintains this utility right-of-way,
which includes clearing and application of herbicides to manage vegetation. National
Grid USA applies herbicides within the easement in accordance with their Yearly
Operational Plan (“YOP”) and in compliance with 333 CMR 11.00, Standards for the
Implementation of Integrated Pest Management Techniques. The YOP must be
submitted to the Massachusetts Department of Food and Agriculture each year.
National Grid USA also provides a copy of the YOP to the chief elected official, the
Board of Health, and the Conservation Commission of every town in which the herbicide
treatment is proposed for that year. Separate notices to each of these entities is also
given at least 21 days prior to the application of herbicides in right-of-ways for each
town where treatment will be carried out.
According to the YOP, biological control is used to control the growth of trees within the
right-of-way, which includes both promoting the establishment of plant communities that
resist invasion by tree species and the judicious and selective use of herbicides on tall
growing trees. Application of herbicides is performed by trained, licensed applicators
using hand-held equipment. Applicators walk to each target plant and apply the minimal
effective dosage of herbicide. National Grid USA uses only those herbicides and
application methods recommended for use in sensitive areas in all the right-of-way
areas, as per 333 CMR 11.04(1)(d).
Hand cutting and mowing is also used as an alternative method of control in sensitive
areas and buffer zones. Herbicide application is prohibited within 100 feet a public
surface water supply and its tributaries, and restricted to selective stem application at an
interval of not less than 24 months, when applied between 100 and 400 feet from a
public surface water supply. Herbicide application is also prohibited within 10 feet of
wetlands or surface water bodies that are not a public water supply and restricted to a
minimum 12-month interval when applied between 10 to 100 feet of these sensitive
areas. The application of herbicides is also restricted to a minimum 12-month interval
when applied within 100 feet of any inhabited area or any agricultural area during the
growing season.
Transmission right-of ways are typically considered adequately regulated, however, a
significant area of right-of-ways exists within the Zone A along the shores of the Aaron
River Reservoir mostly in Cohasset, and partially in Hingham.
RECOMMENDATION 3.25 The Cohasset Board of Water Commissioners in
cooperation with the Cohasset Board of Health and Conservation Commission should
maintain close oversight of the application of herbicides in areas of right-of-ways that
are within the Zone A, and request in writing, advanced notice of any planned
application of herbicides within the Zone A and Zone B areas of the watershed, and an
annual updated copy of the utility company YOP.
3.1.10 Forestry Practices
DEM Land Management.
Land management and management of forests and wetlands by the Massachusetts
DEM adds significantly to the protection of the Watershed. Eco-friendly management
practices conducted across large areas of the Watershed contribute to maintaining a
healthy ecosystem. Forestation provides soil stabilization and buffering. Uptake of
certain pollutants by upland and wetland biota provides a natural means of controlling
pollutant loading on the surface water supply, and bordering vegetative wetlands
provide a natural means of storing and filtering surface water runoff and groundwater.
Forestry practices such as the planned cutting of trees and clearing of the forest floor,
are governed by Massachusetts General Law (MGL) c. 132 Sections 40-46 and codified
under 304 CMR 11.00, Forest Cutting Practices. Non-commercial cutting and small
commercial harvesting of forested areas; (i.e. cutting less than 25,000 board-feet, 50
cords or one parcel of land) at any one time are exempt from this regulation.
Under 304 CMR 11.00, filter strips must be left along the edges of the bank of any water
body. A filter strip is an area of forested land where no more than 50% of the basal
area can be cut at any one time and a waiting time of 5 years must elapse before
another cut is made. The filter strip along Outstanding Resource Waters, such as Lily
Pond, and its associated streams and wetlands, extends back a distance of at least 50
feet, increasing as a function of land slope [see Table 1 in 304 CMR 11.05(1)(d)(2)].
Harvesting equipment restrictions also apply to filter strip areas.
According to the DEM and the Trustee of Reservations, all forestry practices at
Wompatuck State Park and the Woods are in accordance with these regulations.
Therefore, these areas are considered adequately regulated and are not considered a
significant threat to the surface water supply.
Woody Adelgid Infestation.
In some areas of the Watershed, notably along the southeastern side of the Aaron River
Reservoir, the woody adelgid insect has impacted eastern hemlock tree species. This
has resulted in the loss of trees within the filter strip of the reservoir, and is cause for
concern about potential erosion problems.
RECOMMENDATION 3.26 The Towns of Cohasset, Hingham and Scituate should
plant, or encourage the planting (via education and/or a program to supply and plant
saplings) of non-hemlock conifer tree species in areas damaged by woody adelgid
infestation within 50 feet of the Aaron River Reservoir or Lily Pond in order to reduce
potential siltation of the water bodies and maintain slope stability. This planting program
may best be implemented through local conservation commission efforts. The
Cohasset Board of Water Commissioners should discuss such a program with their
local conservation commissioners.
3.1.11 Storage of Fertilizer, Manure, Road Salt
The DEP Matrix categorizes storage of fertilizers as Moderate threats to a surface water
supply, and storage of manure as High threats. There are several areas where
fertilizers or manure are stored within the Watershed. None of these areas, however,
are located within the Zone A. As mentioned above, the MHD currently stores road salt
at their facility located on Scituate Hill in Cohasset. In the summer of 2001, MHD
completed construction of a totally enclosed salt storage facility at the site to prevent
leaching of sodium and chloride into groundwater. There are two garden supply stores
within the Watershed that store small amounts of manure and fertilizer. To the extent
that these products are sold in small quantities in the manufacturers packaging these
are not considered a threat to the surface water supply.
The Town of Cohasset has one road salt storage location at the Cedar Street Landfill,
which is located outside the Watershed. Hingham, Norwell, and Scituate also have salt
storage facilities all of which are located outside the Watershed.
RECOMMENDATION 3.27 The Watershed communities should require that all outdoor
storage of fertilizers or manure be contained in weatherproof enclosures.
3.1.12 New Construction
New construction within the Watershed has the potential to impact the water quality by
erosion, and additional nutrient loading through on-site septic systems and stormwater
run-off. As shown on Maps 1a and 2, much of the land within the Zone A cannot be
developed since it consists of wetland or Protected Open Space. Cohasset, Norwell,
and Scituate by-laws require that contractors take steps to prevent untreated
stormwater runoff and soil erosion during construction. Under EPA’s Phase II
Stormwater Program, construction that disturbs greater than 1 acre of land will require
the filing of an NPDES permit application.
3.1.13 Sand and Gravel Mining/Washing Operations
Contaminants associated with sand and gravel mining/washing operations include
VOCs, SVOCs and petroleum hydrocarbons. The DEP Matrix categorizes these
operations as Moderate threats to a surface water supply. There are no known active
sand and gravel mining/washing operations within the Watershed.
3.2 Water Supply Impacts from Future Land Use
This section reviews the allowable future land uses under current zoning regulations to
determine potential future impacts to the surface water supply.
3.2.1 Protected Areas, Open Space and Municipal Zoning within the Watershed
The Watershed is relatively well protected by municipal zoning, Open Space and
Protected Areas as indicated on Map 2. Protected Areas are those sections of the
Watershed where zoning and/or non-zoning controls have been implemented. Open
Space includes protected areas such as conservation lands and outdoor recreational
facilities. Approximately 63% of the Watershed is designated Open Space.
All land within the Zone A is either residentially zoned, Open Space or Protected Areas.
Most of the land within the Zone B is Protected Areas or Open Space or is zoned
residential with the exception of a small commercially zoned area located northeast of
Lily Pond, and a commercial zone northwest of the Aaron River Reservoir. The Zone C
has within its boundaries Open Space; commercial, residential, and Industrial area is
located in the northwest corner of the Watershed, within the town of Cohasset.
There are several town-designated overlay protection districts that apply within the
Watershed, in addition to municipal zoning. Cohasset approved a Water Resource
District that encompasses all of the land in Cohasset within the Watershed. There are
several other areas in Cohasset that are protected in perpetuity as Open Space and
some lots that are protected as agricultural land.
Hingham land within the Watershed consists of Open Space and residential land. As
indicated above, the Wompatuck State Park and Trustee of Reservations land is
protected in perpetuity as Open Space. Hingham’s Watershed and Aquifer Protection
Districts do not intersect the Watershed and, therefore, provide no protection for the
surface water supply.
Norwell land within the Watershed consists entirely of residential land for single-family
dwellings. Much of Norwell within the Watershed is also protected by Norwell’s Aquifer
Protection District.
Scituate land within the Watershed consists entirely of residential land for single-family
dwellings. All of Scituate’s land within the Watershed is also protected by a Water
Resources Protection District.
3.2.2 Future Land Use Impacts
Cohasset has approximately 1,983 acres of reserved or undeveloped land within the
Watershed, all of which is zoned for residential use. Approximately 70% of the
undeveloped land is wetland or non-accessible and cannot be developed, leaving
approximately 600 acres of developable land. Much of this remaining land area is
protected as Open Space or non-developable wetlands. While there is a part of the
Watershed zoned for business and commercial uses, these zoning districts are subject
to the land use controls of Cohasset’s Water Resource District. In general, the only
foreseeable potential future impact to the surface water supply from land use for this
part of the Watershed is from private on-site septic systems and unexpected releases.
Virtually all of Hingham within the Watershed is protected as Open Space. The Water
Resources Protection Districts in Norwell and Scituate cover substantial areas of the
towns that are within the Watershed, and these regulations provide good protection
from future land impacts.
RECOMMENDATION 3.28 The Watershed communities should allow officials from
each town the chance to review and comment on zoning variances or special permits
for proposed future development. To the best of its ability, town officials in the town
where the zoning variances or special permits apply should incorporate the comments
of the other Watershed town officials into the approval process.
3.3 Public Access/Recreation Impacts
This section reviews the public access policies and recreational impacts that currently
exist in the Watershed.
3.3.1 Public Access to Lily Pond and Aaron Reservoir
The Cohasset Water Department currently provides limited public access to Lily Pond
and the Cohasset Water Department and the DEM jointly provide public access to the
Aaron River Reservoir. Both Lily Pond and the reservoir are protected from general,
unrestrained public access by heavily forested areas, wetlands as well as private
residential lots to the east.
Recreational use of Lily Pond, the Aaron River Reservoir, Pape Reservation, Bound
Brook Pond, and the Aaron River is limited to picnicking, rowing, fishing, and hiking.
The use of sailboats, motorboats, and powerboats in these areas is prohibited. There
are currently no local restrictions on walking or riding domestic animals in these areas.
The impacts to the surface water supply from these non-restricted activities are
considered insignificant. Swimming and all water contact sports are prohibited.
Canoeing is also restricted on the Aaron River Reservoir by prior agreement with the
state in accordance with Massachusetts General Laws, Ter. Ed. Chapter 111, Section
160.
RECOMMENDATION 3.29 The Cohasset Board of Water Commissioners should post
signs at the public access ways for both Lily Pond and the Aaron River Reservoir that
indicate allowed and prohibited activities within these water bodies.
3.4 Wildlife Impacts
3.4.1 Existing or Potential Water Supply Impacts from Wildlife
The DEP Matrix categorizes aquatic wildlife as a HIGH threat to a surface water supply.
According to the Cohasset Wildlife Officer, no large populations of any one species of
animal exist within the Watershed. Wildlife typical for the area includes deer, fox,
coyote, skunks, raccoons, beaver, and opossum. Turtles live in the pond, and have
been known to get inside the grate for the water treatment plant intake. Approximately
seven families of Canadian geese have also been residing near Lily Pond over the past
several years. Canadian geese are known to create problems in water supplies,
including excessive fecal coliform bacteria contamination. Beavers are not currently a
problem in the Watershed.
RECOMMENDATION 3.30 The Cohasset Board of Water Commissioners should take
steps to discourage geese and other nuisance wildlife from roosting near Lily Pond.
One method gaining in popularity is to employ the use of dogs such as the Border
Collie. These animals tirelessly pursue geese on the ground and provide a harmless
threat that discourages the geese from setting up roost. The dogs are available for sale
through kennels that specifically train them for this purpose. A Water Department
employee or neighboring property owner could be “hired” to keep the trained dog and
patrol the site periodically.
3.4.2 Existing or Potential Water Supply Impacts from Domestic Animals
Cohasset records show that 6 horses are registered at locations within the Watershed.
Norwell records indicate 4 horses are stabled within Zone B of the Watershed.
Hingham and Scituate have no available records of horses within the Watershed. Small
stable operations located outside of the Zone A are not considered a significant threat to
the surface water supply.
3.5 In-Lake Problems
3.5.1 Existing or Potential In-Lake Problems
In 1985, CDM performed a preliminary assessment of the trophic state of Lily Pond20.
CDM suggested that Lily Pond was, at that time, in a eutrophic or borderline
mesotrophic/eutrophic state. As discussed above, a more recent evaluation indicates
that Lily Pond and the Aaron River Reservoir are eutrophic, or borderline hyper-
eutrophic. A discussion of this recent evaluation follows.
As part of this SWSPP, a current evaluation of the trophic state of Lily Pond was
performed using the Vollenweider model and the Carlson Trophic State Index (CYSI).
The estimated hydraulic residence time of the water in Lily Pond and analytical data
collected over the past three years from the pond and its tributaries formed the basis for
this assessment. Based on the Vollenweider model results it appears that Lily Pond is
in a eutrophic state.
The results of the assessment were checked by comparing the total phosphorous
concentrations in Lily Pond to the Carlson Trophic State Index (CTSI). According to the
CTSI, index values over 50 are considered eutrophic, and index values over 70 are
considered hyper-eutrophic. The average index value obtained for Lily Pond, based
upon phosphorous readings over the past three years was 68, which supports the
results of the Vollenweider model that Lily Pond is eutrophic. For several of the
sampling periods, the index value exceeded 70 indicating at these times the pond could
be considered hyper-eutrophic.
20 Water Resource Management Report, Camp Dresser & McKee, March 1986
The CTSI for the average concentration of total phosphorus in the Aaron River
Reservoir is 74, indicating the reservoir is also hyper-eutrophic.
In addition, another indicator of in-lake problems occurred in July of 1998, when the
intake to the water treatment plant was clogged by aquatic weeds preventing any water
from getting into the plant. The potential for excessive aquatic plant growth and the
spread of nuisance weeds in the pond is a threat to the water supply probably
associated with the high concentration of nutrients in the water. Long-term prevention
and/or management of this condition requires monitoring nutrient levels in the pond and
implementation of the various recommendations aimed at the reduction of nutrient
loading as set forth in this SWSPP.
3.6 Other Areas of Concerns
According to the USGS Bedrock Geologic Map of Massachusetts by E-an Zen, bedrock
across the entire Watershed is the Dedham Granite. Groundwater flow through bedrock
is along fractures, and can move in different directions from flow in the overburden.
Bedrock fractures are known to exist within the Watershed northwest of Lily Pond and
likely exist throughout the Watershed. The potential exists for impacted groundwater
that migrates into bedrock to travel to the surface water supply or tributaries along these
fractures. Groundwater flow through bedrock fractures can significantly reduce the
migration time and diffusion, attenuation and retardation of contaminants in the
groundwater compared to flow through soil. This is a concern since the CHL Landfill,
MHD salt storage site, and the Norfolk Conveyor Site, all located northwest of Lily Pond,
are known sources of contamination to groundwater. These releases to groundwater,
while occurring relatively far away from the surface water supply, could impact Lily Pond
via transport through the bedrock fractures. The Cohasset Board of Water
Commissioners has installed three (3) deep groundwater-monitoring wells in some of
these bedrock fractures to monitor the groundwater quality in the fractures. Minor
concentrations of contaminants typical of landfill leachate have recently been detected
in the wells, which are monitored on a quarterly basis.
As recommended above, the Cohasset Board of Water Commissioners should continue
to monitor these wells so that potential migration of contaminants via bedrock fractures
can be detected before they impact Lily Pond.
4.0 SAMPLING PLAN
4.1 Previous Surface Water Sampling
Prior to preparing the sampling plan recommendations noted later in this chapter, it was necessary to
review the several different historic sources of surface water testing data for the watershed. These
sources, in order of historic date, are discussed briefly below:
1. Surface water quality test results reported in “Hydrogeological and Water Quality Study of
Watersheds Tributary to Lily Pond and Great Swamp in the Area of Scituate Hill”, prepared
by CDM, November 1984. Data is reported based on surface water samples near and
down gradient of the CHL landfill. The surface water data in this report demonstrated that
certain surface water quality constituents (specifically chloride and sulfate) exceeded typical
background levels, and were attributable to leachate and/or underdrain discharges from the
CHL landfill that was in operation at the time. (Not all of the testing data in this source is
relevant to the Lily Pond watershed since some of the data related to impacts to the
neighboring Great Swamp watershed).
2. Surface water quality test results reported in “Water Resources Management Plan”,
prepared by CDM, March 1986. Data is reported based on sampling of Lily Pond (surface
and bottom samples), Peppermint Brook, Brass Kettle Brook, Aaron River Reservoir
outflow, and Bound Brook at the control structure. The surface water data demonstrated
that the most elevated contaminant levels (compared to typical pristine background levels)
were found in Peppermint Brook, which is understandable as it is located in the most
densely developed portion of the watershed. Elevated phosphorous levels found in the
pond bottom sample and in Bound Brook are believed related to the anoxic conditions (low
oxygen levels) that were found in the pond bottom water. The indications were that the
pond sediments, under anoxic conditions, are releasing phosphorous and other inorganic
elements. Also, low levels of alkalinity were found in the pond indicating a reduced
buffering capacity of the pond due to acid rain.
3. Surface water quality test results reported in “Report on Potential Contaminant Migration
from Cohasset Landfill to Lily Pond”, prepared by Norfolk Environmental, October 1998.
This report includes a compilation of historic data from landfill monitoring by others,
supplemented by new surface water sampling of a stream that originates at CHL landfill
and continues south to Brass Kettle Brook. Conductivity was measured as a general
indicator of contamination (particularly chloride) in surface water, which showed a decrease
in conductivity with increasing distance from the landfill. Also, several surface water points
along the same stream were sampled and tested for volatile organic compounds, chemical
oxygen demand, chloride, chromium and lead. This surface water data was consistent in
demonstrating that certain surface water quality constituents downgradient of the landfill
(specifically chloride, COD, lead and toluene) exceeded typical background levels, and
were attributable either to leachate and/or underdrain discharges from the CHL landfill, or
to other upgradient sources (e.g. Webb/Norfolk Conveyor site, Mass. Highway site).
4. Surface water quality test results reported in the “Cohasset Water Quality Study, Cohasset,
MA”, prepared by U.S. Army Corps of Engineers, February 1999. The Army Corps of
Engineers conducted a limited watershed study that included sediment and surface water
quality tests to check for possible contamination from the former Hingham Annex waste
site, the CHL landfill and residential areas tributary to the Aaron River and Lily Pond.
Watershed related data includes sediment test data for Brass Kettle Brook at four stations
located progressively further from CHL landfill, and surface water test data for Peppermint
Brook at King Street, and Aaron River at Doane Street and Union Street. The test results
indicated some elevated levels of lead in Brass Kettle Brook, with a pattern of decreasing
lead levels from the station closest to the landfill to the station closest to Lily Pond,
indicating a possible upstream source. Another area of possible concern raised by the
study was the elevated levels of fecal coliforms and nitrate in Peppermint Brook.
5. Surface water quality test results reported for CHL Landfill (state required landfill
monitoring). Surface water testing continues to occur quarterly in areas downgradient of
the CHL landfill, and Norfolk Ram Group, as consultants for the Cohasset Board of Water
Commissioners, have been reviewing and summarizing this data on a regular basis. The
most significant aspect of the results from this regular testing is the data consistently show
that surface waters downgradient of the landfill are impacted by elevated sodium and
chloride contamination. (This reports also consistently show that groundwater, considered
separately due to pathway differences, is also significantly affected by sodium, chloride,
and the volatile organic compound 1, 4 dichlorobenzene in excess of drinking water
standards.)
The above noted historic data reports were considered along with regular testing of the water supply
and tributaries, as sampled semi-annually by Tutela Engineering (Tutela) from mid 1998 to mid 2000,
and as sampled quarterly by Norfolk Ram Group (Norfolk) from September 2001 through March
2002. The following locations have been sampled by Tutela, and parameters analyzed (that varied
by location) included total phosphate, total kjeldahl nitrogen (TKN), total and dissolved sodium, pH,
and temperature.
x Lily Pond, at 1-foot below surface
x Brass Kettle Brook
x Peppermint Brook
x Aaron River Reservoir, at the outfall
x Bound Brook, at the control structure
x Brook from Flat Swamp, below Clapp Road in Scituate
Norfolk’s surface water testing included the first four of those locations noted above along with the
following additional locations (with some changes by quarter, depending upon parameters being
tested):
x Lily Pond, deep samples
x Herring Brook Outlet at Lily Pond
x Aaron River near Doane Street Crossing
x Aaron River Reservoir, deep samples
x Aaron River Reservoir, west side near Hingham Annex
x Outlet of Stream from South Swamp, Scituate, (S.E. area, Aaron River Reservoir)
x Outlet of Aaron River into the reservoir in Hingham
The Norfolk sampling parameters (that varied be sample location) included dissolved oxygen, pH,
conductivity, temperature, turbidity, alkalinity, carbon dioxide, COD (chemical oxygen demand),
chlorides, fecal coliform, orthophosphate, total phosphorous, total nitrogen (TKN), nitrate-nitrogen,
volatile organic compounds (voc’s), and metals. The results for the Tutela / Norfolk testing from
1998/99 through 2001 are included in the data table that presents the latest March 2002 short term
sampling that was performed as part of this SWSPP. These data are discussed below.
4.2 Short-Term Sampling
As shown in Table 4-1, a comprehensive short-term sampling plan was devised and implemented as
part of this SWSPP in order to identify or confirm any contamination sources in Lily Pond, Aaron River
Reservoir and their tributaries. The surface water data collected through this effort was used in
consideration of historic data and known land uses and potential threats to devise a long-term
sampling strategy for the Watershed.
The nine (9) locations of short term surface water sampling, performed as part of this SWSPP are
designated on Map 1b as Sample #1 through Sample #9. These locations were selected on the basis
of prior sampling records noted above and the location of known or suspected sources of
contamination. Consideration was given to concerns over potential releases of contaminants from
the Cohasset Heights Landfill site, Massachusetts Highway Department facility, Norfolk Conveyor,
and military storage bunkers in Wompatuck State Park. The parameters of concern with the greatest
potential impact on the watershed include volatile organic compounds, heavy metals, sodium,
phosphorus and nitrate.
Norfolk Ram Group collected surface water samples at the nine locations indicated on Map 1b for this
SWSPP on March 7, 2002. These latest test results are presented in Table 4-2 along with related
historical test data form the Tutela / Norfolk testing. Also, charts are provided in Figures 3 through 14
that provides a visual review of the data from Table 4-2 along with some of the test data from the
1985 CDM report and the 1998
Army Corps report, (noted in the section above). It is important to note that each sampling event is a
“snapshot” of the conditions at each sampling point and that the results of each sampling event must
be interpreted in context of the natural characteristics of the water body, normal seasonal fluctuations,
and temporary sampling conditions in order to see the larger “moving picture” that more accurately
describes the surface water quality.
The results of the analysis of the water quality parameters listed in Table 4-2 indicate that most
parameters are in “normal” ranges for each of the sample locations. There were some deviations
from the “normal” trend line noted for certain parameters in samples collected from the outlet of
Peppermint Brook (Sample #3) and at the outlet of the Aaron River (Sample #9). Deviations were
found for alkalinity, chlorides, conductivity and nitrate in samples collected from the outlet of
Peppermint Brook into Lily Pond. Deviations were found for pH and turbidity at the outlet of the Aaron
River into the Aaron River Reservoir. These two sample locations are very close to roads that have
no stormwater control devices. Most of these deviations in the short-term sampling can be attributed
road salt runoff.
The analytical results confirm that uncontrolled stormwater runoff from roads have a significant impact
on contaminant loading to the surface water supplies, and that action needs to be taken to control this
source of contamination.
Sample Location No.Sampling LocationVOC'sSDWA -13 MetalsSDWA -5 MetalsPCB'sCODTOCFecal ColiformTotalPhosphorusAlkalinityAlgaeChloridesTKNNitrateColorDOpHConductivityTurbidityTemperatureRationale for Sampling1Outlet of Brass Kettle Brook at Lily pond X X X X XXXXXPrior Releases, Landfills2a.Lily Pond - Shallow SamplesXX XXX XXXXXXX Water Supply2b.Lily Pond - Deep SamplesXX XXXXXXXXXXXXXXX Water Supply3Peppermint Brook Outlet at Lily PondXXXXXXXXXXXSeptic, Stormwater Runoff4Herring Brook Outlet at Lily PondX X XXXXXInlet from Reservoir5Aaron River near Doane Street CrossingXX X X XXXXXSeptic, Stormwater Runoff6a.Aaron River Reservoir - Shallow SamplesX X X XXXXXXX Water Supply6b.Aaron River Reservoir - Deep SamplesXX X XXX X XXXXXXX Water Supply7Aaron River Reservoir - West side near Hingham Annex XXXXXXXKnown Release Site8Outlet of stream from South Swamp in ScituateX X XXX XXX XXXXXSeptic, Stormwater Runoff9Outlet of Aaron River into Reservoir in HinghamX XXX XXX XXXXXSeptic, Stormwater Runoff2241112649283841111111111Total Number of SamplesTABLE 4-1SURFACE WATER SUPPLY PROTECTION PLAN FORLILY POND & AARON RIVER RESERVOIRSHORT-TERM SAMPLING PLAN LOCATIONS AND PARAMETERS
TABLE 4-2aQuarterly Water Sampling ResultsSample LocationOutlet of Brass Kettle Brookat Lily PondLocation #1Lily PondShallow SamplesLocation #2aLily PondDeep SamplesLocation #2bOutlet of Peppermint Brookat Lily PondLocation #3Outlet of Herring Brookat Lily PondLocation #4Aaron River near Doane StreetLocation #5Aaron River ReservoirShallow SamplesLocation #6aAaron River ReservoirDeep SamplesLocation #6bAaron River ReservoirWest side near Hingham AnnexLocation Outlet of Streamfrom South Swamp in ScituateLocation #8Outlet of Aaron Riverat Aaron River Reservoirin HinghamLocation 7/27/99NTNTNTNTNTNT NT NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 1.86 7.1 NT 7.42 2.78 7.91 8.76 NT NT NT 7.5912/6/01 10.4 10.37 9.64 10.84 10.6 12.86 11.46 11.58 12.11 10.3 11.023/7/02 10.45 12.58 12.53 11.47 11.59 12.45 12.89 12.16 12.57 12.7 12.861/7/99 3.87 5.47 NT 5.89 NT NT 5.48 NT NT NT NT4/7/99 5.59 6.6 NT 6.49 NT NT 6.69 NT NT NT NT5/13/99 5.45 6.39 NT 6.08 NT NT 6.46 NT NT NT NT6/16/99 5.02 5.25 NT 5.68 NT NT 5.94 NT NT NT NT7/27/99 NSF 6.52 NT 6.28 NT NT 6.44 NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 7.65 7.23 NT 6.9 6.48 7.3 7.29 NT NT NT 6.412/6/01 7.31 7.33 7.4 7.47 7.6 8.06 7.31 7.21 7.11 7.12 8.073/7/02 7.3 6.85 6.86 6.34 6.87 6.7 6.39 5.24 6.45 6.38 6.587/27/99NTNTNTNTNTNT NT NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 108 128 NT 127 110 111 107 NT NT NT 12412/6/01 153.2 151.3 148 147.7 141.6 105.6 109.3 111.5 111 114.7 104.83/7/02 48 110 109 286 80 96 75 75 71 144 74Sample DateDissolved Oxygen (pH (field, s.u.)Conductivity (mS/cm
TABLE 4-2bQuarterly Water Sampling ResultsSample LocationOutlet of Brass Kettle Brookat Lily PondLocation #1Lily PondShallow SamplesLocation #2aLily PondDeep SamplesLocation #2bOutlet of Peppermint Brookat Lily PondLocation #3Outlet of Herring Brookat Lily PondLocation #4Aaron River near Doane StreetLocation #5Aaron River ReservoirShallow SamplesLocation #6aAaron River ReservoirDeep SamplesLocation #6bAaron River ReservoirWest side near Hingham AnnexLocation #7Outlet of Streamfrom South Swamp in ScituateLocation #8Outlet of Aaron Riverat Aaron River Reservoirin HinghamLocation #91/7/99 6.9 6.8 NT 4.4 NT NT 5.0 NT NT NT NT4/7/99 17.6 13.1 NT 13.1 NT NT 12.5 NT NT NT NT5/13/99 17.5 18.6 NT 13.6 NT NT 16.3 NT NT NT NT6/16/99 23.1 23 NT 15.5 NT NT 23 NT NT NT NT7/27/99 NSF 28.1 NT 18.9 NT NT 28.7 NT NT NT NT6/1/00 20.5 22.1 NT 16.3 NT NT 21.7 NT NT NT NT9/25/01 19.48 19.88 NT 20.96 19.7 22.69 22.25 NT NT NT 20.8212/6/01 13.9 12.4 15.1 12.2 13.08 18.09 15.5 16.71 20.47 16.26 17.133/7/02 4.11 5.5 5.44 6.71 4.78 6.09 5.27 5.24 5.98 4.6 5.817/27/99NTNTNTNTNTNTNTNTNTNTNT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 7.6 1.7 NT 4 1.9 13.6 7.2 NT NT NT 14.612/6/01 51 42.5 35 34.5 43.8 57.7 52.2 57.7 56.8 40 51.33/7/02 2.2 1.4 1.2 1.4 1 3.7 0.8 7 2.2 0.9 100.77/27/99NTNTNTNTNTNTNTNTNTNTNT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 5.8 5.8 NT 6.8 5.8 NT 3.9 NT NT 3.9 2.912/6/01875812NT21NT4ND3/7/02 <2.0 5 6 20 <2.0 NT 3 <2 NT 3 <27/27/99NTNTNTNTNTNTNTNTNTNTNT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01NT9.5NTNTNTNTNTNTNTNTNT12/6/01 NT 19 7.9 NT NT NT NT NT NT NT NT3/7/02 NT NT NT NT NT NT NT NT NT NT NTCarbon Dioxide (mg/L)SampleDateTemperature (deg C)Turbidity (NTU)Alkalinity (mg/L as CaCo3)
TABLE 4-2cQuarterly Water Sampling ResultsSample LocationOutlet of Brass Kettle Brookat Lily PondLocation #1Lily PondShallow SamplesLocation #2aLily PondDeep SamplesLocation #2bOutlet of Peppermint Brookat Lily PondLocation #3Outlet of Herring Brookat Lily PondLocation #4Aaron River near Doane StreetLocation #5Aaron River ReservoirShallow SamplesLocation #6aAaron River ReservoirDeep SamplesLocation #6bAaron River ReservoirWest side near Hingham AnnexLocation #7Outlet of Streamfrom South Swamp in ScituateLocation #8Outlet of Aaron Riverat Aaron River Reservoirin HinghamLocation #97/27/99 NT NT NT NT NT NT NT NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 29 32 NT 34 38 34 27 NT 14 20 5712/6/01 24 19 33 28 17 29 ND 31 24 16 653/7/02 32 32 NT 22 36 32 32 27 29 39 353/7/02 NT 9.7 9.2 NT NT NT NT NT NT NT NT3/7/02 NT 50 50 NT NT NT 120 120 NT NT NT7/27/99 NT NT NT NT NT NT NT NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 26 32 NT 33 NT NT 28 NT NT 29 3312/6/01 29 33 30 33 NT NT 28 27 NT 28 363/7/02 12 39 38 110 NT NT 30 30 NT 62 287/27/99 NT NT NT NT NT NT NT NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 NT NT NT ND NT 10 NT NT NT 10 27012/6/01 NT NT 20 20 NT ND NT ND NT ND ND3/7/02 NT NT <10 20 NT <10 NT <10 NT 10 <107/27/99 NT NT NT NT NT NT NT NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 NT ND NT NT NT NT NT NT NT NT NT12/6/01 NT ND 0.02 NT NT NT NT NT NT NT NT3/7/02 NT NT NT NT NT NT NT NT NT NT NTChloride+A9 (mg/L)Fecal Coliform (# per 100 ml)Orthophosphate (mg/L)Sample DateCOD (mg/L)TOC (mg/L)Color (ADMI)
TABLE 4-2dQuarterly Water Sampling ResultsSample LocationOutlet of Brass Kettle Brookat Lily PondLocation #1Lily PondShallow SamplesLocation #2aLily PondDeep SamplesLocation #2bOutlet of Peppermint Brookat Lily PondLocation #3Outlet of Herring Brookat Lily PondLocation #4Aaron River near Doane StreetLocation #5Aaron River ReservoirShallow SamplesLocation #6aAaron River ReservoirDeep SamplesLocation #6bAaron River ReservoirWest side near Hingham AnnexLocation #7Outlet of Streamfrom South Swamp in ScituateLocation #8Outlet of Aaron Riverat Aaron River Reservoirin HinghamLocation #97/2/98 NT 0.11 NT NT NT NT NT NT NT NT NT7/14/98 0.22 0.12 NT NT NT NT 0.22 NT NT NT NT1/7/99 0.26 0.2 NT 0.23 NT NT 0.15 NT NT NT NT3/3/99 0.15 0.12 NT 0.14 NT NT 0.09 NT NT NT NT4/7/99 0.69 < 0.05 NT 0.11 NT NT 0.13 NT NT NT NT5/13/99 0.44 0.08 NT 0.19 NT NT 0.09 NT NT NT NT6/16/99 0.93 0.1 NT 0.32 NT NT 0.07 NT NT NT NT7/27/99nsf0.09NT0.26NTNT0.17NTNTNTNT6/1/000.30.06NT0.26NTNT0.08NTNTNTNT9/25/01 NT 0.01 NT NT NT NT NT NT NT 0.03 0.0312/6/01NTNDNDNTNTNTNTNDNTND0.013/7/02 NT NT 0.29 NT NT NT NT <.05 NT 0.056 <.057/27/99 NT NT NT NT NT NT NT NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT NT9/25/01 NT 0.18 NT 0.18 NT 0.21 0.17 NT NT ND 0.1912/6/01 NT ND ND ND NT 0.1 0.08 0.06 NT 0.07 ND3/7/02 NT <.03 0.22 0.96 0.25 NT 0.088 NT NT 0.091 <.037/27/99 NT NT NT NT NT 0.6 NT NT NT 2 NT6/1/00 NT NT NT NT NT 0.8 NT NT NT 1.1 NT9/25/01 NT 0.11 NT NT NT NT NT NT NT NT NT12/6/01 NT 0.4 ND NT NT NT NT NT NT NT NT3/7/02 NT NT NT NT NT NT NT NT NT NT NTTotal Nitrogen (mg/L)Nitrogen as Nitrate (mg/L)SampleDateTotal Phosphorus as Phosphate (mg/L)
TABLE 4-2eQuarterly Water Sampling ResultsSample LocationOutlet of Brass Kettle Brookat Lily PondLocation #1Lily PondShallow SamplesLocation #2aLily PondDeep SamplesLocation #2bOutlet of Peppermint Brookat Lily PondLocation #3Outlet of Herring Brookat Lily PondLocation #4Aaron River near Doane StreetLocation #5Aaron River ReservoirShallow SamplesLocation #6aAaron River ReservoirDeep SamplesLocation #6bAaron River ReservoirWest side near Hingham AnnexLocation #7Outlet of Streamfrom South Swamp in ScituateLocation #87/2/98 NT 0.9 NT NT NT NT NT NT NT NT7/14/98 1.2 1.0 NT NT NT NT 0.8 NT NT NT1/7/99 < 0.5 < 0.5 NT 1 NT NT 0.7 NT NT NT3/3/99 < 0.5 <0.5 NT <0.5 NT NT <0.5 NT NT NT4/7/99 2.6 < 0.5 NT 0.6 NT NT <0.5 NT NT NT5/13/99 3.8 0.7 NT 0.7 NT NT <0.5 NT NT NT6/16/99 5.6 0.6 NT 0.6 NT NT 0.5 NT NT NT7/27/99 NSF 1.1 NT 0.8 NT NT 0.6 NT NT NT6/1/00 3 1.1 NT NT NT NT 0.8 NT NT NT9/25/01 NT 0.28 NT NT NT NT NT NT NT NT12/6/01 NT ND ND NT NT NT NT NT NT NT3/7/02 NT NT 0.16 NT NT NT NT NT NT 0.187/27/99 NT NT NT NT NT NT NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT9/25/01 ND NT NT NT NT NT ND NT NT NT12/6/01 ND NT ND NT NT NT NT ND NT NT3/7/02 NT NT ND NT NT NT NT ND NT NT7/27/99 NT NT NT NT NT NT NT NT NT NT6/1/00 NT NT NT NT NT NT NT NT NT NT9/25/01 NT NT NT ND NT NT NT NT ND ND12/6/01 NT NTCr-0.00345 Zn-0.00610ND NT NT NT Zn-0.0166 ND ND3/7/02 ND (5) NT ND ND (5) NT NT NT ND ND (5) ND (5)FOOTNOTES:ND = Non (5) SDWA-5 metals TestedNT = Not tensf = no surface flowSample DateTotal Keldahl Nitrogen (mg/L)Volatile Organic Compounds (µg/L)SDWA-13 Metals (mg/L)
Figure 3Surface Water Dissolved Oxygen024681012147/28/01 9/16/01 11/5/01 12/25/01 2/13/02 4/4/02Time (Sampling Date)Dissolved Oxygen (mg/L)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow2b.) Lily Pond - Deep3.) Peppermint Brook - Lily Pond4.) Herring Brook - Lily Pond5.) Aaron River - Doane Street6.) Aaron River Reservoir - Shallow6b.) Aaron River Reservoir - Deep7.) Aaron River Reservior - West8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River ReservoirClass A Water Body Minimum CriteriaLily Pond - Shallow (CDM, 6/7/85)Lily Pond - Deep (CDM, 6/7/85)Brass Kettle Brook (CDM, 6/7/85)Peppermint Brook - Lily Pond (CDM, 6/7/85)Aaron River Reservoir (CDM 6/7/85)Peppermint Brook - Lily Pond (Army Corp, 5/7/98)Aaron River - Doane Street (Army Corp, 5/7/98)Reference Data(1985 and 1998)
Figure 4Surface Water pH (1999)012345678911/01/1998 12/21/1998 02/09/1999 03/31/1999 05/20/1999 07/09/1999 08/28/1999Time (Sampling Date)pH (s.u.)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow3.) Peppermint Brook - Lily Pond6.) Aaron River Reservoir - ShallowClass A Water Body Criteria Upper LimitClass A Water Body Criteria Lower LimitLily Pond - Shallow (CDM, 6/7/85)Lily Pond - Deep (CDM, 6/7/85)Brass Kettle Brook (CDM, 6/7/85)Peppermint Brook - Lily Pond (CDM, 6/7/85)Aaron River - Doane Street (Army Corp, 5/7/98)Aaron River - Doane Street (CDM, 6/7/85)Peppermint Brook - Lily Pond (Army Corp, 5/7/98)Reference Data(1985 and 1998)XXXXNNOTE: pH levels down to 5.6 are not unusual in New England where acid rain falls on soils of granite origin which have poor buffering capacity.
Figure 4aSurface Water pH (2000-2002)012345678909/06/200109/26/200110/16/200111/05/200111/25/200112/15/200101/04/200201/24/200202/13/200203/05/200203/25/2002Time (Sampling Date)pH (s.u.)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow2b.) Lily Pond - Deep3.) Peppermint Brook - Lily Pond4.) Herring Brook - Lily Pond5.) Aaron River - Doane Street6.) Aaron River Reservoir - Shallow6b.) Aaron River Reservoir - Deep7.) Aaron River Reservior - West8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River ReservoirClass A Water Body Criteria Upper LimitClass A Water Body Criteria Lower LimitNOTE: pH levels down to 5.6 are not unusual in New England where acid rain falls on soils of granite origin which have poor buffering capacity.
Figure 5Surface Water Conductivity0501001502002503003507/28/01 9/16/01 11/5/01 12/25/01 2/13/02 4/4/02Time (Sampling Date)Conductivity (mS/cm)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow2b.) Lily Pond - Deep3.) Peppermint Brook - Lily Pond4.) Herring Brook - Lily Pond5.) Aaron River - Doane Street6.) Aaron River Reservoir - Shallow6b.) Aaron River Reservoir - Deep7.) Aaron River Reservior - West8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River ReservoirPeppermint Brook - Lily Pond (Army Corp, 5/7/98)Aaron River - Doane Street (Army Corp, 5/7/98)Reference Data(1985 and 1998)
Figure 6Surface Water Temperature051015202530357/24/98 2/9/99 8/28/99 3/15/00 10/1/00 4/19/01 11/5/01 5/24/02Time (Sampling Time)Temperature (oC)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow2b.) Lily Pond - Deep3.) Peppermint Brook - Lily Pond4.) Herring Brook - Lily Pond5.) Aaron River - Doane Street6.) Aaron River Reservoir - Shallow6b.) Aaron River Reservoir - Deep7.) Aaron River Reservior - West8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River Reservoir
Figure 7Surface Water Turbidity0204060801001209/6/01 9/26/01 10/16/01 11/5/01 11/25/01 12/15/01 1/4/02 1/24/02 2/13/02 3/5/02 3/25/02Time (Sampling Date)Turbidity (NTU)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow2b.) Lily Pond - Deep3.) Peppermint Brook - Lily Pond4.) Herring Brook - Lily Pond5.) Aaron River - Doane Street6.) Aaron River Reservoir - Shallow6b.) Aaron River Reservoir - Deep7.) Aaron River Reservior - West8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River Reservoir------Allowed level after treatment at plant
Figure 8Surface Water Alkalinity0510152025307/28/01 9/16/01 11/5/01 12/25/01 2/13/02 4/4/02Time (Sampling Date)Alkalinity Concentration (mg/L as CaCo3)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow2b.) Lily Pond - Deep3.) Peppermint Brook - Lily Pond4.) Herring Brook - Lily Pond6.) Aaron River Reservoir - Shallow6b.) Aaron River Reservoir - Deep8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River ReservoirLily Pond - Shallow (CDM 6/7/85)Lily Pond - Deep (CDM 6/7/85)Brass Kettle Brook - Lily Pond (CDM 6/7/85)Peppermint Brook - Lily Pond (CDM 6/7/85)Aaron River Reservoir (CDM 6/7/85)
Figure 9Surface Water COD0102030405060709/6/01 9/26/01 10/16/01 11/5/01 11/25/01 12/15/01 1/4/02 1/24/02 2/13/02 3/5/02 3/25/02Time (Sampling Date)COD Concentration (mg/L)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow3.) Peppermint Brook - Lily Pond4.) Herring Brook - Lily Pond5.) Aaron River - Doane Street6.) Aaron River Reservoir - Shallow7.) Aaron River Reservior - West8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River Reservoir
Figure 10Surface Water Chloride02040608010012007/28/2001 09/16/2001 11/05/2001 12/25/2001 02/13/2002 04/04/2002Time (Sampling Date)Chloride Concentration (mg/L)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow2b.) Lily Pond - Deep3.) Peppermint Brook - Lily Pond6.) Aaron River Reservoir - Shallow6b.) Aaron River Reservoir - Deep8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River ReservoirLily Pond - Shallow (CDM, 6/7/85)Lily Pond - Deep (CDM, 6/7/85)Brass Kettle Brook (CDM, 6/7/85)Peppermint Brook - Lily Pond (CDM, 6/7/85)Aaron River - Doane Street (CDM, 6/7/85)Peppermint Brook (Army Corp, 5/7/98)Aaron River - Doane Street (Army Corp, 5/7/98)Reference Data Points(1985 and 1998)The Massachusetts Secondary Maximum Contaminant Level (SMCL) for chloride is 250 mg/L.
Figure 11Surface Water Fecal Coliform Counts0501001502002503003507/28/01 9/16/01 11/5/01 12/25/01 2/13/02 4/4/02Time (Sampling Date)Fecal Coliform Concentration (ct/100 mL)2b.) Lily Pond - Deep3.) Peppermint Brook - Lily Pond5.) Aaron River - Doane Street8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River ReservoirClass A Water Body Maximum CriteriaPeppermint Brook - Lily Pond (Army Corp, 5/7/98)*Aaron River - Doane Street (Army Corp, 5/7/98)Reference Data Points(1998)*Standard for Class A waters "shall not exceed an arithmetic mean of 20 organisms per 100 mL in any representative sample, nor shall 10% of the samples exceed 100 organisms per 100 mL".
Figure 12Surface Water Orthophosphate00.010.020.030.040.050.069/16/01 9/26/01 10/6/01 10/16/01 10/26/01 11/5/01 11/15/01 11/25/01 12/5/01 12/15/01Time (Sampling Date)Orthophosphate Concentration (ppm)2b.) Lily Pond - DeepLow End of Natural Conc. Range for Orthophosphate*High End of Natural Conc. Range for Orthophosphate*All other sample locations = 0 ppm*From Dunne and Leopold, 1978
Figure 13Surface Water Total Phosphorus00.10.20.30.40.50.60.70.80.9112/1/96 6/19/97 1/5/98 7/24/98 2/9/99 8/28/99 3/15/00 10/1/00 4/19/01 11/5/01 5/24/02 12/10/02Time (Sampling Date)Total Phosphorus Concentration (mg/L)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow3.) Peppermint Brook - Lily Pond6.) Aaron River Reservoir - Shallow8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River ReservoirLily Pond - Shallow (CDM 6/7/85)Lily Pond - Deep (CDM 6/7/85)Brass Kettle Brook - Lily Pond (CDM 6/7/85)Peppermint Brook - Lily Pond (CDM 6/7/85)Aaron River Reservoir (CDM 6/7/85)Recommended Maximum Conc. (mg/L) in Lakes/Reservoirs*Reference Data Points(1985)* Recommended concentration for lakes/reservoirs to control algal growth, from EPA water quality criteria 1986. The comparable EPA recommended concentration for streams that discharge into lakes and reservoirs is 0.05 mg/L. Also, the reported average concentration for euthrophic lakes is 0.084 mg/L (Vollenweider & Kerekes, 1980).
Figure 14Surface Water Total Keldahl Nitrogen01234566/19/97 1/5/98 7/24/98 2/9/99 8/28/99 3/15/00 10/1/00 4/19/01 11/5/01 5/24/02Time (Sampling Date)TKN Concentration (ppm)1.) Brass Kettle Brook - Lily Pond2.) Lily Pond - Shallow2b.) Lily Pond - Deep3.) Peppermint Brook - Lily Pond4.) Herring Brook - Lily Pond5.) Aaron River - Doane Street6.) Aaron River Reservoir - Shallow6b.) Aaron River Reservoir - Deep7.) Aaron River Reservior - West8.) Unnamed Stream - Aaron River Reservoir9.) Aaron River - Aaron River ReservoirLily Pond - Shallow (CDM 6/7/85)Lily Pond - Deep (CDM 6/7/85)Lily Pond - Shallow (CDM 6/7/85)Peppermint Brook - Lily Pond (CDM 6/7/85)Aaron River Reservoir (CDM 6/7/85)Mean Concentration (mg/L) Associated with Eutrophication*Reference Data Points(1985)* From Vollenweider & Kerekes, 1980. Mean concentrations for oligotrophic and mesotrophic given as 0.66 and 0.75 mg/L, respectively.
RECOMMENDATION 4.1 Stormwater Best Management Practice (BMP) controls should be
implemented at roads within the Zone A of the Watershed. Also, the water quality parameters with
deviations from normal found at the aforementioned locations should be closely observed over the
next few quarterly sampling rounds to determine if these deviations in water quality are indicative of
long-term problematic water quality issues or merely seasonal fluctuations.
4.3 Proposed Long-Term Sampling Plan
4.3.1 Surface Water
In order to provide a good indication of the success of the Watershed protection efforts and to monitor
known contaminants of concern and progression in the trophic state of Lily Pond, a Long-Term
Sampling Plan is proposed as indicated in Table 4-3. The Long-Term Sampling Plan also takes into
consideration sampling that will be required under new upcoming regulations that will impact the
water treatment plant.
RECOMMENDATION 4.2 The Cohasset Board of Water Commissioners should implement this
proposed Long-Term Sampling Plan for a period of at least three years to observe the seasonal
variations in contaminant concentrations.
As of the publishing of this report the Quarterly Sampling Plan includes the eleven surface water-
sampling points as shown on Map 1b. These surface water sampling points include the nine short-
term sample locations (Sample #1 through Sample #9) and two addition sampling points (Sample #10
and Sample #11) which were added to the list after public comment of the draft review. This plan
may continue to be modified as areas of concern are either added or eliminated over time.
Lily Pond and the Aaron River Reservoir have a number of surface water tributaries that can carry
contaminants of concern from well beyond the immediate area of these water bodies. Each of the
tributaries may be impacted by land use, stormwater runoff, or the release of hazardous material into
the environment nearby.
RECOMMENDATION 4.3 The Cohasset Board of Water Commissioners Sampling at the surface
water locations shown in Map 1b should be performed on a quarterly basis, and each location should
be sampled for the parameters recommended in the long-term sampling plan summary Table 4-3.
Location No.Sampling LocationVOC'sSDWA -13 MetalsSDWA -5 MetalsPCB'sCODTOCFecal ColiformTotal PhosphorusAlkalinityAlgaeChlorides/SodiumTKNNitrateColorDOpHConductivityTurbidityTemperatureRationale for Sampling1.Outlet of Brass Kettle Brook at Lily pond X X XX X XXXXXPrior Releases, Landfills2a.Lily Pond - Shallow Samples XX XXX XXXXXXX Water Supply2b.Lily Pond - Deep Samples XX XXXXXXXXXXXXXXX Water Supply3.Peppermint Brook Outlet at Lily PondX X XXX X X XXXXXSeptic, Stormwater Runoff4.Herring Brook Outlet at Lily PondX X XXXXXInlet from Reservoir5.Aaron River near Doane Street CrossingXX X X X XXXXXSeptic, Stormwater Runoff6a.Aaron River Reservoir - Shallow SamplesX X X XXXXXXX Water Supply6b.Aaron River Reservoir - Deep SamplesXX X XXX X XXXXXXX Water Supply7.Aaron River Reservoir - West side near Hingham Annex X X XXXXXKnown Release Site8.Outlet of stream from South Swamp in ScituateX X XXX XXX XXXXXSeptic, Stormwater Runoff9.Outlet of Aaron River into Reservoir in HinghamX XXX XXX XXXXXSeptic, Stormwater Runoff10.East Side of Aaron River ReservoirX XX X XXXXXSeptic, Stormwater Runoff11.Brass Kettle Brook near Howes RoadXX X XX X X XXXXXPrior Releases, LandfillsTotal Number of Samples 3 3 4 1132 7 81021031041313131313Sampling ParametersTABLE 4-3LONG-TERM SAMPLING PLAN LOCATIONS AND PARAMETERSSURFACE WATER SUPPLY PROTECTION PLAN FORLILY POND & AARON RIVER RESERVOIR99-04 SWT/ SURFACE WATER PROTECTION GRANT
4.3.2 Groundwater – Bedrock Pathways
Much of the historic water quality data that exists for the Watershed has been collected between Lily
Pond and the Cohasset Heights Landfill site. A 1998 study by Norfolk Environmental evaluated this
data and the potential for contamination of the watershed by CHL landfill. The 1998 Norfolk study
found that groundwater transport is a viable potential threat to the Watershed since significant water
bearing bedrock fractures were found to exist that could channel contaminants from the Landfill to
Brass Kettle Brook and into Lily Pond. For this reason, three deep bedrock wells were installed to
intercept the water bearing bedrock fractures, and quarterly monitoring was initiated for volatile
organic compounds, chemical oxygen demand, chloride, and the five “landfill” metals (antimony,
arsenic, cadmium, chromium, and lead). To date, testing of these bedrock wells has not detected
contaminant migration through bedrock fractures, although there have been some isolated dections of
contaminents. Total antimony was detected in MW-4 at a concentration of 0.0094 milligrams per liter
(mg/L) for the third quarter sampling event. This concentration exceeds the MMCL for total antimony
of 0.006 mg/L. The total antimony concentration for the fourth quarter 2001 and first quarter 2002
sampling events, however, were below the laboratory PQL, and hence the MMCL. This suggests the
detection of total antimony during the third quarter event may be related to the extreme climate
conditions experienced by the northeast during the period leading up to the third quarter sampling
event. Often, heretofore undetected contaminants show up in groundwater samples during periods of
low recharge from precipitation. This may be a result of a reduction in the dilution of the contaminant,
a change in the nature of the groundwater chemistry, or a shift in the preferential travel pathway of
the contaminant. Once climatic conditions shift towards normal, the “new” contaminant is no longer
detected, as occurred for total antimony during the fourth quarter 2001 sampling event. While the
lack of detection of total antimony for the fourth quarter 2001 suggests a “one-time” occurrence, it is
important to closely watch this contaminant since, according to the Environmental Protection Agency
(EPA), antimony potentially causes health effects, such as nausea, vomiting and diarrhea when
people are exposed to it at levels above the MMCL for relatively short periods of time. EPA requires
public water systems where antimony is consistently detected above the MMCL to remove the
contaminant using suitable treatment technologies.
The concentration of total dissolved solids (TDS) detected at MW-4 for the third quarter sampling
event (690 mg/L) exceeded the SMCL of 500 mg/L. TDS can be an indicator of pollutant impacts to
groundwater since excessive TDS concentrations can be attributed to heavy contaminant loading.
The TDS concentration for the fourth quarter 2001 and first quarter 2002 sampling events, however,
dropped well below the SMCL to 94 mg/L, suggesting the third quarter result may be associated with
the low recharge from precipitation.
The concentrations of sulfate detected during the fourth quarter 2001 sampling event in all three wells
exceeded the SMCL for drinking water and were at least two orders of magnitude greater than
previously detected. The detected concentrations of sulfate in MW-1 (1,900 mg/L), MW-3 (1,800
mg/L) and MW-4 (5,700 mg/L) significantly exceeded the SMCL standard of 250 mg/L. For the first
quarter 2002, the sulfate concentrations in all three wells dropped below the SMCL. The cause of the
increased sulfate concentrations for the fourth quarter 2001 sampling event is not currently known.
According to the EPA, health concerns such as diarrhea may be associated with the ingestion of
water containing high concentrations of sulfate. As with total antimony, it is important to closely watch
this contaminant over time to determine if the fourth quarter 2001 increases indicate a shift upward in
the trend of sulfate concentrations in the wells.
However, these should continue to be monitored quarterly at least for the next two (2) years. These
three (3) groundwater-sampling locations are also shown on Map 1b.
5.0 LAND USE CONTROLS
The control of existing and potential future land use within the Watershed is one of the most effective
methods to ensure the long-term viability and usefulness of Lily Pond and the Aaron River Reservoir
as surface water supplies. This section reviews land use controls that are in place, and recommends
measures that should be developed for the long-term prevention and control of existing and potential
sources of contamination within the Watershed. Map 2, Appendix A illustrates the various types of
land use controls and the areas within the Watershed where they exist, and these controls are
discussed in detail below.
5.1 Land Purchase or Deed Restriction
The Cohasset Water Department has been actively pursuing a policy of protecting the surface water
supply by land purchase or deed restriction. These acquisitions include taking land by eminent
domain illustrated by a plot of land near the outlet of the Aaron River Reservoir and Beechwood
Street acquired in July 2001. In addition, the Cohasset Water Commission has preliminarily
evaluated all lots of developable land in Cohasset within the Zone A (and parcels abutting Zone A
parcels) with the intent of purchasing some of these properties over the next 3-5 years. The
purchase of (or protection through establishing conservation deed restrictions) strategically important
properties will aid in the protection of the surface water supply. Figure 15 below illustrates the extent
of these parcels evaluated by the Cohasset Water Commission.
RECOMMENDATION 5.1 The Cohasset Board of Water Commissioners should further evaluate (as
to feasibility and priority) the developable land parcels located within the Zone A areas (including
developable parcels that abut parcels in Zone A); and then pursue acquisition for open space, or
restrictions for such parcels. The priority for plan years one through three should be parcels in Zone
A along Lily Pond, Aaron River Reservoir and tributaries thereto; priority for plan years four through
six should be parcels that abut parcels in the Zone A (for the pond, reservoir and tributaries); and
priority for years seven through ten should be Zone B parcels closest to Zone A areas. The
Commissioners should work cooperatively with existing town boards such as the Open Space
Committee and the Community Preservation Committee to share resources and information
regarding land acquisition priorities.
The Town of Cohasset owns land to the immediate north and northwest of Lily Pond. The protection
afforded by the deed restrictions for these properties designated Open Space is unknown. Also, the
Assessor’s records indicate certain substantial tracts of land that are classified as undevelopable (see
Map 3) and many of these are located within the Zone A or Zone B areas of the Watershed.
RECOMMENDATION 5.2 The Cohasset Board of Water Commissioners should investigate the
deeds to town-owned land to the immediate north and northwest of Lily Pond, and if necessary
strengthen the protections to maximize surface water supply protection.
RECOMMENDATION 5.3 The Cohasset Board of Water Commissioners should consider parcels
presently recorded as undevelopable within the Zone A for possible Town Open Space acquisition or
for securing protective conservation deed restrictions (see Map 3). The priority for plan years one
through three should be parcels in Zone A along Lily Pond, Aaron River Reservoir and tributaries
thereto; priority for plan years four through six should be parcels that abut parcels in the Zone A (for
the pond, reservoir and tributaries); and priority for years seven through ten should be Zone B parcels
closest to Zone A areas.
In addition, there are numerous parcels located within or abutting the Zone A of Lily Pond where the
Assessor’s records indicate unknown ownership (see Map 4).
RECOMMENDATION 5.4 The Cohasset Board of Water Commissioners should evaluate the
possibility of acquiring parcels located within or abutting the Zone A of Lily Pond where the
Assessor’s records indicate unknown ownership, (see Map 4). The priority for plan years one through
three should be parcels in Zone A along Lily Pond, Aaron River Reservoir and tributaries thereto;
priority for plan years four through six should be parcels that abut parcels in the Zone A (for the pond,
reservoir and tributaries); and priority for years seven through ten should be Zone B parcels closest to
Zone A areas.
The Town of Scituate has taken steps to purchase some parcels of land within the Watershed to
preserve as Open Space. One such parcel is the former Clapp Landfill.
5.2 ACECs and Protected Open Spaces
Areas of Critical Environmental Concern (ACECs) are places in Massachusetts that receive special
recognition because of the quality, uniqueness, and significance of their natural and cultural
resources. These areas are identified and nominated at the community level, and reviewed and
designated by the state’s Secretary of Environmental Affairs. The ACEC designation creates a
framework for local and regional stewardship of these resources.
As shown on Map 2, Appendix A none of the land within the Watershed is designated ACEC. The
South Swamp tributary and associated wetland system located north of Clapp Road in Scituate, as
well as the unique habitat and resource value of the South Swamp located south of Clapp Road and
partly in the Watershed, are excellent candidates for ACEC status. Preliminary discussions about this
possibility have recently been initiated by the residents of Scituate.
RECOMMENDATION 5.5 The Watershed communities should identify potential areas within the
Watershed to nominate for ACEC status such as the South Swamp tributary and associated wetland
system watershed located north of Clapp Road in Scituate, as well as the unique habitat and
resource value of the South Swamp located south of Clapp Road and partly in the Watershed.
Cohasset. Roughly one-half of Cohasset’s land within the Watershed is designated Open Space,
which is protected by conservation restrictions, perpetuity, or other land-use restrictions. Land within
the Wompatuck State Park is owned and operated by the Massachusetts DEM, and consists of 2,400
acres west and southwest of Lily Pond and the Aaron River Reservoir. This land is protected in
perpetuity as Open Space. The Trustee of Reservations owns Thayer and Whitney Woods, which
consists of approximately 950 acres north and northwest of Lily Pond and is protected in perpetuity
and/or by conservation restriction as Open Space. The Barbara Churchill Conservation Area, located
just north of Bound Brook, the Campbell Meadow, located northeast of Lily Pond, and the Andrus
property located east of Lily Pond are also protected in perpetuity as Open Space. Other parcels of
land such as the Charlie Pape Reservation located northwest of Lily Pond, and land abutting the
northwest side of Lily Pond owned by the Water Department are designated as Open Space, but are
not protected in perpetuity.
Hingham. Ninety-eight percent of the Hingham land within the Watershed is designated as Open
Space protected in perpetuity as Wompatuck State Park and Trustee of Reservations land. The only
Hingham land within the Watershed not protected as Open Space consists of developed residential
land northwest of Lily Pond.
Norwell. Approximately 85 acres of Norwell land within the Watershed is designated Open Space
and protected in perpetuity or by conservation restrictions. The Norwell Aquifer Protection District
overlays a large percentage (90%) of Norwell land within the Watershed.
5.3 Land Use and Activity Controls
5.3.1 Septic Systems
The Town of Cohasset has recently implemented a plan for upgrading and improving private septic
systems within the Watershed. The Comprehensive On-Site Wastewater Management Plan
prepared by the Cohasset Board of Health is a voluntary plan that Cohasset citizens may join to
receive town-managed services for their residential septic systems if they pass a Title 5 Inspection.
The management plan offers 20-year loans to homeowners to repair/upgrade their septic systems
should they fail at some future date. Other services to members include Title 5 Inspections, annual
evaluations, tank pumping (typically, every three years), maintenance, repair, and upgrades.
Cohasset also offers “Septicredits” for residents who have land that could be used as a resource for
treatment of sanitary wastewater from other properties requiring repair or upgrade. Owners of this
land would receive credits and/or cash payments for the use of their land in this manner.
The Norwell Board of Health has identified the entire town as nitrogen sensitive as defined in 310
CMR 15, primarily because of the large number of private wells in the town. This program will help to
reduce septic system density for new construction.
RECOMMENDATION 5.6 The towns of Cohasset, Norwell and Scituate should evaluate all older
septic systems (installed prior to 1978) within 200 feet of the surface water supply to determine if they
are properly functioning in accordance with 310 CMR 15.303(2). Where it is determined that septic
systems fail to protect the public health and safety and the environment, the towns should require that
the systems be upgraded to meet current Title 5 Standards. Cohasset should consider modifying
their Storm Water Management Plan to include funding these actions through the Septicredit
program.
5.3.2 Stormwater Runoff
No-Salt Zones.
Roadside snow pack has been documented as a major contributor of pollutants that are bound up
with the snow from airborne and roadway deposition. Pollutants migrating into Peppermint Brook
from roadside runoff are carried a relatively short distance and discharged into Lily Pond near the
intake of the water treatment plant. Pollutants from Peppermint Brook pose a significant threat to the
surface water supply due to the proximity of the water treatment plant to the discharge of Peppermint
Brook.
RECOMMENDATION 5.7 The Cohasset Board of Water Commissioners should request that the
MHD designate the area along Route 3A where it is tributary to Peppermint Brook a no-salt zone.
RECOMMENDATION 5.8 The Cohasset Board of Water Commissioners should file a Notice of Intent
with the Town of Norwell Conservation Commission to designate Mt. Blue Street and Mount Hope
Street within the Zone B near Bound Brook Pond no-salt zones.
Stormwater Drainage.
Stormwater drainage systems within the Watershed in the Town of Cohasset are largely unmapped.
Cohasset has begun efforts to locate and identify catch basins and stormwater discharge points. In
particular, sudden roadside releases caused by vehicular accidents pose a significant threat to
Peppermint Brook along sections of Route 3A. The Town of Cohasset Planning Department has
submitted an application to the DEP for a Watershed Improvement Grant. The grant money as well
as matching funds from the town would be put towards a town-wide mapping effort to located and
describe the storm water drainage system in Cohasset. The stormwater mapping project would serve
as a critical component in analyzing the Watershed, identifying non-point sources of contamination
within the Watershed, and provide sustainable protection of the surface water supply into the future.
RECOMMENDATION 5.9 Continued joint efforts between the Cohasset Board of Water
Commissioners, Board of Health, DPW, and Planning Board to accomplish stormwater drainage
system mapping on a town-wide basis should be pursued. A town-wide GIS, which would include
storm drain system mapping, requires the participation of many town departments to ensure that
relevant data remains accurate and up to date once initial mapping is completed. If funds are limited,
mapping Zone A and Zone B areas and threatened coastal and wetland areas should be pursued as
an immediate priority
RECOMMENDATION 5.10 The Cohasset Board of Water Commissioners should evaluate the
feasibility of installing stormwater treatment systems along Route 3A where it comes in close
proximity to Peppermint Brook and along King Street where drainage is tributary to Lily Pond and
especially within the Zone A. Following the feasibility study, treatment systems should be designed
and constructed to capture roadway spills, oil and other petroleum products to prevent their discharge
into Peppermint Brook.
5.4 Municipal Land Use Improvements
Municipal activities that could have an impact on surface water sources include road salt use and
storage, chemical use and storage, composting or recycling facilities, sites of permanent or one-day
household hazardous waste collection events, motor oil collection centers, underground storage
tanks, gasoline pumps, vehicle repair operations, public recreation areas, and on-site septic systems.
RECOMMENDATION 5.11 The Watershed communities should periodically review municipal land
uses in the Watershed to ensure that any activities that have the potential to adversely impact the
surface water supply are identified and addressed as necessary through site improvements and/or
facility management plans.
5.4.1 Water Treatment Plant Improvements
Off-site Disposal of Wastewater and Sludge.
The water treatment plant currently disposes of its sanitary wastewater by pumping to the new sewer
on King Street. However, dried sludge from two-water treatment plant settling lagoons is currently
stored on-site in a drying bed. Lead and arsenic have been detected in recent samples collected
from both lagoons and the drying bed. This is likely due to concentrating naturally occurring lead and
arsenic through the filtration process.
RECOMMENDATION 5.12 The Cohasset Board of Water Commissioners should evaluate the
potential for off-site disposal of the sludge pursuant to 310 CMR 32.00, the Land Application of
Sludge and Septage regulation.
5.5 Lawn Management
The proximity of Beechwood Cemetery and Beechwood Park to the Zone A along the Aaron River
raises the concern that pesticides, herbicides, and fertilizers used to treat the landscaped areas might
enter into the surface water supply.
Cohasset and all watershed communities should initiate a Lawn Care Management Program aimed at
informing homeowners, lawn care specialists, landscape design professionals, and others involved in
lawn care of the detrimental effects of the “perfect lawn” paradigm. The goal of this program should
be to reduce the overall loading of nutrients, pesticides and herbicides in the Watershed.
RECOMMENDATION 5.13 The Cohasset Board of Water Commissioners in partnership with Boards
of Health in the Watershed communities should develop and implement a Lawn Care Management
Program for all areas within the Zone A and all town-owned properties. The plan should define areas
where the application of lawn care chemicals is prohibited such as within 200 feet of the surface
water supply or tributaries, and establish recommended application procedures and frequencies for
areas within the Zone B.
Also, Article XIII, Section 4(c) of the Cohasset General Bylaws requires that commercial lawn care
companies notify the Cohasset Board of Health seven (7) days prior to applications within the Water
Resource District (WRD). However, enforcement of this bylaw is reported to be lacking due to
insufficient staffing and funding. Implementation of this bylaw would provide the town with: 1).
information on the amounts of pesticides and herbicides being applied within the WRD; and 2).
provide opportunity to communicate with, and educate commercial contractors regarding town WRD
policies (e.g., Lawn Care Management Program, if developed).
RECOMMENDATION 5.14 The Cohasset Board of Water Commissioners should work on
partnership with the Board of health to properly fund and implement the existing bylaw Article XIII
Section (c) that applies to Commercial Lawn Care notifications prior to pesticide/herbicide
applications in the WRD.
5.6 Management Plan
RECOMMENDATION 5.15 A written management plan should be developed for town-owned land
within the Watershed. This management plan should include regular inspections to look for
unauthorized activity, illegal dumping, obstructions to stream flow, missing signs, and other
maintenance needs.
6.0 PUBLIC ACCESS/ RECREATION CONTROL
6.1 Public Access to Water Supply Areas
The public has very limited access to Lily Pond due to the surrounding wetland and forests.
RECOMMENDATION 6.1 The Cohasset Board of Water Commissioners should install a fence at Lily
Pond near the water treatment plant to limit public access at that location, and signs should be posted
listing the recreational activities that are allowed and prohibited.
There is limited public access to the Aaron River Reservoir via Beechwood Street. A chain link fence
borders the property at the end of Beechwood Street but is currently in a state of disrepair. The
Water Commission is reported to be proceeding with repairs to fencing in this area.
RECOMMENDATION 6.2 The Cohasset Board of Water Commissioners should repair the fence to
the Aaron River Reservoir via Beechwood Street, install a gate, and install public accommodations
(i.e. stairs and/or ramps).
6.2 Recreation Control
RECOMMENDATION 6.3 The Watershed communities should develop a walking trail around Aaron
River Reservoir that would serve to define and control the specific areas the public can utilize. This
walking trail should be set back from the edge of the reservoir so as to provide a minimum 25-foot
buffer zone. Trash containers placed at strategic locations along the trail would help control trash in
the area.
6.3 Wildlife Management
6.3.1 Canadian Geese
The presence of Canadian geese is a common problem associated with many water bodies. A
sizeable population of geese can significantly add to the nutrient loading. The town is currently
considering methods of controlling the geese population in the Lily Pond area.
RECOMMENDATION 6.4 The Cohasset Board of Water Commissioners should take steps to
discourage geese and other nuisance wildlife from roosting near Lily Pond. One method gaining in
popularity is to employ the use of dogs such as the Border Collie. These animals tirelessly pursue
geese on the ground and provide a harmless threat that discourages the geese from setting up roost.
6.4 In-Lake Management
The Cohasset Board of Water Commissioners is very concerned about the state of eutrophication of
Lily Pond and has already taken positive steps to reduce the nutrient loading. The nutrient loading in
the Aaron River Reservoir is also high. Therefore, the following steps should be taken to further
protect the Pond and Reservoir, and minimize the potential for further eutrophication.
6.4.1 Limnology Study of the Pond and Reservoir
As discussed above, the trophic state of both Lily Pond and the Aaron River Reservoir is eutrophic to
hyper-eutrophic. This information is based upon limited sampling and analysis results and doesn’t
take into account seasonal fluctuations in nutrient levels. Cohasset was recently awarded a $25,000
state grant by the DEM as part of the 2002 Lake and Pond Grant Program to conduct a more
comprehensive limnology and water’s edge study of Lily Pond that will include both a diagnostic and
feasibility evaluation. The study should include an assessment of the trophic state of Lily Pond and
the Aaron River Reservoir based upon the seasonal measurements of chemical constituents. The
analytical results should be compared to literature values and past results to develop a thorough
understanding of the 1) trophic state of the water bodies as a function of time, and 2) the major
nutrient input sources.
A component of the study should be to gain some understanding of the relationship between the
makeup of the water’s edge and overland flow as it contributes to nutrient loading.
RECOMMENDATION 6.5. The Town of Cohasset should conduct a limnology and water’s edge
study of Lily Pond and Aaron River Reservoir to include both a diagnostic and feasibility evaluation.
An assessment of the trophic state of both the pond and the reservoir based upon the seasonal
measurement of chemical constituents, and the relationship between the makeup of the water’s edge
and nutrient loading should be components of the study.
6.4.2 Annual Eutrophication Assessment
The proposed long-term sampling plan previously discussed can provide a year-round picture of the
effects of nutrient loading on the Pond. This information would be valuable to the Town to assist
them in take preventative or remedial measures that will maintain the viability of the Pond as a
surface water supply. Such measures may include aquatic flora reduction, control of stormwater
runoff, sewer system expansion and/or stricter septic system regulations.
RECOMMENDATION 6.6 The Cohasset Board of Water Commissioners should implement the long-
term sampling plan to monitor nutrient concentrations in Lily Pond and Aaron River Reservoir and all
tributaries. The sampling results should be assessed by an experienced limnologist to update the
Town on the state of eutrophication of Lily Pond and Aaron River Reservoir.
7.0 REGULATORY CONTROLS
Local Regulations are an effective method for controlling existing and future potential sources of
contamination within the Watershed. This section examines the Watershed communities’ existing
local and state regulations relative to the protection of the Watershed, and recommends where they
can be strengthened to provide greater protection in the future.
7.1 Current Local Water Resources Protection Regulations
7.1.1 Zoning By-laws
As shown on Map 2, the Watershed consists of several zoning districts including Open Space,
Residential, Commercial, and Technology Business. Each town within the Watershed has their own
zoning by-laws to regulate land use and control development within these districts.
Open Space.
State laws and local zoning by-laws restrict most development of Open Space areas.
Most of the Open Space within the Watershed such as Wompatuck State Park and Trustee of
Reservations Land is protected in perpetuity. Other Open Space land within the Watershed is
protected by “something other than time”. Typically, only passive use of Open Space land is allowed,
however, in some cases, other uses are allowed with a Special Permit usually from the town’s Zoning
Board of Appeals.
RECOMMENDATION 7.1 The Cohasset Board of Water Commissioners should research the deeds
for Open Space, which is protected by “something other than time” so that the degree of protection is
understood, and if necessary strengthen the protections to maximize surface water supply protection.
Residential.
Each town within the Watershed allows residential zoning. Residential districts basically allow single-
family residences. Non-commercial agricultural land use is also allowed within these districts.
Commercial/Technology Business.
The Town of Cohasset has commercial/technology business zoning within the Watershed allowing
office buildings with commercial and/or technology business operations.
7.1.2 Water Resources Protection Districts
As shown on Figure 2, the Water Resources Protection Districts overlay a substantial area of the
Watershed. These districts consist of the Cohasset Water Resource District, the Norwell Aquifer
Protection District, and the Scituate Water Resource Protection District. Cohasset’s Water Resource
District (which is the primary protection district for the watershed) was first adopted in 1986 and
updated in 2000 to conform to the most recent DEP regulations
These districts provide regulatory protection by prohibiting some land use known to have the potential
to adversely effect surface water supplies, providing stricter regulations on discharges of pollutants to
air or water, and restricting storage of oil or hazardous materials. The regulations of the Water
Resources Protection Districts are in addition to municipal zoning regulations.
Regulatory Protection.
Table 7-1 compares the protection provided by each of the town’s Water Resources Protection
Districts. Cohasset bylaws are designed to protect their surface water supply. Protection of the
surface water supply as proposed in this SWSPP should be a component of Cohasset’s master plan,
and the Growth and Development Committee could prove a valuable asset in this effort. Note that
current Norwell and Scituate bylaws are designed to protect their groundwater water supply
resources. The Town of Hingham does not have any Water Resources Protection Districts within the
Watershed.
RECOMMENDATION 7.2 Cohasset should include the protection of the surface water supply as a
component of the town’s master plan. The Growth and Development Committee has drafted a vision
statement that reads in part “Prudent planning and careful management of the town’s natural
resources protect the quality and quantity of the town’s waters – drinking water supply, streams,
wetlands, and coastal waters.” Moreover, water supply protection has emerged, via surveys and
public meetings, as a key concern and top priority. The master plan must balance a variety of issues
and priorities as expressed by various stakeholders during the process. The recommendations of the
SWSPP should be considered very carefully along with other top community priorities.
RECOMMENDATION 7.3 Cohasset should prohibit the following land uses within the Zone A of the
Watershed: commercial car/truck washes; dry-cleaning establishments; metal plating, finishing, or
polishing; chemical or bacteriological laboratories; commercial photographic processing; commercial
printing other than xerographic reproduction; self-service laundries unless sewered; hotels or motels
unless sewered; cabinet/furniture making establishments; painting, wood preserving, and furniture
stripping establishments; and electronic circuit assembly facilities. The Cohasset Board of Water
Commissioners should enlist the support of the Zoning Advisory Committee, which is a sub-
committee of the Planning Board when proposing future zoning changes.
RECOMMENDATION 7.4 Norwell should prohibit the following land uses within the Zone A of the
Watershed: cabinet/furniture making establishments; painting, wood preserving, and furniture
stripping establishments; electronic circuit assembly facilities; and outside storage of herbicides,
pesticides, or fertilizer in amounts exceeding normal household or agricultural use.
RECOMMENDATION 7.5 Scituate should prohibit the following land uses within the Zone A of the
Watershed: non-sanitary treatment/disposal works subject to 314 CMR 5.00; and the removal of soil
within four feet of the high groundwater elevation.
PROHIBITED USES IN WATER RESOURCES PROTECTION DISTRICTS
Cohasset Norwell Scituate
Sanitary landfills X X X
Salvage/Junk yards X X X
Commercial Car/Truck washes X X
Road Salt/ De-icing material storage X X X
Dumping of Snow from outside of District X X X
Dry-cleaning establishments X X
Metal plating, finishing, or polishing X X
Chemical or bacteriological laboratories X X
Commercial photographic processing X X
Commercial printing, other than xerographic reproduction X X
Self-service laundries, unless sewered X X
Hotel or motel, unless sewered X X
Airplane, boat, motor vehicle service and repair/ auto body shops X X X
Non-sanitary treatment/disposal works subject to 314 CMR 5.00 X X
Removal of soil within four feet of the high groundwater elevation X X
Installation of UST’s (except septic systems) X X X
Cabinet /Furniture-making establishments X
Electronic circuit assembly X
Painting, wood preserving, and furniture stripping establishment X
Municipal sewage treatment facilities with on-site disposal of
primary or secondary treatment effluent XXX
Storage and/or sale of petroleum or refined petroleum products,
except within the building for heating XXX
Outside storage of herbicides, pesticides, or fertilizer, in amounts
exceeding normal household or agricultural use XX
Notes:
X = Land use prohibited by existing regulation
TABLE 7-1
SURFACE WATER SUPPLY PROTECTION PLAN FOR
LILY POND & AARON RIVER RESERVOIR
7.1.3 Conservation Commission Bylaws
Cohasset’s Wetlands Bylaw.
The Town of Cohasset’s wetlands bylaw is summarized below.
Cohasset has adopted a General By-law for wetlands protection (Article XIV). This by-law prohibits
any discharge from a landfill into the Watershed. Additional protective measures include erosion and
sedimentation control.
The Cohasset Conservation Commission has adopted wetlands regulations that provide guidance for
activities in the 100-foot buffer zone, and generally require a 50-foot buffer strip be maintained
between all non-water dependent projects and the resource area. The goal of the regulations is to
maintain a dense, continuous, woody vegetative cover within the buffer strip to provide wildlife
habitat, improve water recharge, reduce pollution, reduce erosion, and maintain aesthetic appeal.
Activities within the buffer strip are generally limited to light pruning
Norwell’s Wetlands Bylaw.
The Town of Norwell’s wetlands bylaw, titled Article XVI-A is summarized below.
Buffer Zone.
The prime concern of the Commission in the buffer zone is the ultimate impact on adjacent wetland
resource of the construction and the use phases of the proposed activity. The goal of the
Commission is to maintain a dense habitat, improve water recharge, reduce pollution, and reduce
erosion. Work within the buffer zone may qualify for a Request for Determination rather than filing of
a Notice of Intent.
Fifty Foot (50’) Buffer Strip Regulation.
No activity or alteration shall be permitted within a fifty foot (50’) buffer strip between any proposed
site disturbance and a bordering vegetated wetland as defined in Chapter 131, Sec. 40 or isolated
vegetated wetland defined as any area where surface or ground water, is at or near the surface of the
ground and greater than five hundred square feet which supports a plant community (cover)
comprised of 50 percent or greater of wetlands species, or which in the judgment of the Commission
supports significant community of wetland vegetation.
Prohibited activities include, but are not limited to, new construction (with the exception of water
dependant structures approved by the Commission) of buildings, sheds, driveways, and alterations to
existing structures; or activities resulting in the removal, filling or altering of land within the buffer zone
adjacent to a bordering vegetated wetland or isolated wetland, as defined by this bylaw regulation.
This regulation shall not be construed to preclude maintenance of an already existing structure within
the fifty foot (50’) buffer strip.
The Norwell Conservation Commission may allow the prohibited activities when the applicant makes
a clear and convincing showing that the proposed work or its natural and consequential impacts and
effects will not adversely affect the wetlands.
Scituate’s Wetlands Bylaw.
The Town of Scituate’s wetlands bylaw, titled Section 30770 – Wetlands Protection Rules and
Regulations is summarized below.
The regulations set forth by the Scituate Wetland Regulations (SWR 10.00 – 10.99) are intended to
enhance wetlands protection and to provide uniformity to the procedural requirements outlined in the
bylaw for work in or near wetlands.
These regulations parallel the State Wetland Regulations 310 CMR 10.00, but provide more stringent
control where it has been deemed appropriate to adequately protect wetland resource areas within
Scituate.
The interests protected under the bylaw are as follows:
x Protection of public and private water supply;
x Protection of groundwater;
x Flood control;
x Storm damage prevention;
x Prevention of pollution;
x Protection of fisheries;
x Protection of shellfish; and
x Protection of wildlife habitat.
7.1.4 Activities Requiring Special Permits
The Town of Cohasset requires a Special Permit for the following:
x Rendering impervious more than 40% of a lot area within the Water Resource District.
All stormwater runoff from impervious surfaces must be recharged on-site via
subsurface infiltration through vegetative surfaces, unless infeasible (due to site
conditions) or undesirable (due to pollution risks);
x On-site sewage disposal greater than 500 gallons per day if within 500 feet of Lily Pond,
the Aaron River Reservoir, the Aaron River, Peppermint Brook, or Brass Kettle Brook;
and
x Installation of floor drains unless directed to an impervious retention facility for
controlled removal.
Source reduction efforts are required as a condition of Special Permits and include limitations on
parking area de-icing materials and periodic cleaning or renovation of pollution control devices such
as catch basins.
7.1.5 Hazardous Materials Restrictions
Cohasset has adopted a General By-law to ensure the safe storage of hazardous materials (Article
XIII). Article XIII includes registration requirements for underground storage tanks and more stringent
standards for land-use activities in the Water Resource District. Provisions in the Water Resource
District By-law (Section 14 of the Zoning By-laws) severely restrict the storage of hazardous materials
within the District.
The Town of Cohasset has adopted an article amending their Zoning By-laws to prohibit the granting
of a use variance for any land use in the Water Resource District and in any other zoning district,
except Commercially zoned area. This article allows the Town to have more control over the siting of
private solid waste facilities and other potential high-risk land uses.
7.1.6 Title 5 Septic System Regulations
The towns of Cohasset and Norwell have adopted regulations that supplement the Title 5 Standards.
Cohasset requires that any septic system newly installed or being upgraded within 400 feet of a water
body in the Watershed must pass the performance standards for Nitrogen Sensitive Areas. Soil
absorption systems in Norwell must be greater than 100 feet from a wetland. Septic tanks and
distribution systems must be greater than 50 feet from a wetland, and all plans must show whether
the area is in the Aquifer Protection District or a nitrogen sensitive area.
7.2 State Regulations
The State of Massachusetts provides regulatory control for public surface water supplies under 310
CMR 22.20B. These regulations require that public water systems prohibit various activities on or in
the public water source and its tributaries, including access to the public water source and tributaries
by animals and activities associated with maintaining livestock or other domestic animals within 100
feet. The regulation also requires the prohibition of burials within 100 feet of the high water mark of a
public water source or tributary, and compliance with Title 5 Standards for all on-site subsurface
sewage disposal systems within the Zone A, B, or C of the surface water supply. New or expanded
land use within Zone A of the surface water supply that entails the installation of underground storage
tanks, aboveground storage tanks for most liquid hazardous materials (unless it is within a building or
has an appropriate secondary containment system), and treatment or disposal works, must be
prohibited by the public water system.
RECOMMENDATION 7.6 All towns within the Watershed should incorporate the requirements of the
Drinking Water regulation to the Zones A, B, and C of the surface water supply, pursuant to 310 CMR
22.20B.
8.0 EMERGENCY PLANNING
8.1 Emergency Response Plans
The Cohasset Water Department has updated their Emergency Response Plan21, which provides
guidelines for procedures, operations, resources, and communication in emergency conditions. The
water service contractor for the Town, American Water Services (AWS), provides an Incident
Commander and an Emergency Response Team (ERT) to make decisions, utilize resources, and
implement response activities in emergency situations so as to minimize hazards to human health,
property damage, or the environment. ERT’s are available 24-hours per day for emergency duties.
The Emergency Response Plan covers the following anticipated emergencies:
x power outages;
x equipment failures;
x chlorination failure;
x pump failures;
x operator illness/strikes/job actions;
x chemical contamination of supply;
x chemical spills;
x vandalism/sabotage/bomb threats;
x fire;
x main breaks;
x snow and severe weather; and
x biological outbreaks.
The Emergency Response Plan is reviewed quarterly and revised annually by AWS. The towns of
Hingham, Norwell, or Scituate do not have emergency response plans for emergencies occurring in
the areas of the Watershed within these towns.
21 Cohasset Emergency Response Plan, AWT, 2001
8.2 Emergency Response Training
RECOMMENDATION 8.1 Inter-community emergency response training should be conducted on a
routine basis in conjunction with local fire departments from the Watershed communities to coordinate
response activities that may be necessary to address potential emergencies in each of the
communities. Also, the Cohasset Water Department should meet with the Cohasset Fire Department
and the fire departments for the other three watershed communities to 1). Confirm locations of critical
tributary areas where spills are most likely to affect the water supply; and 2). Confirm a consistent set
of spill or release response measures including pre-approved spill response contractors.
9.0 EDUCATION PROGRAM
As part of the SWSPP, a community education program (the PROGRAM) was developed, which is
considered a vital part of the SWSPP since the protection of any surface water supply depends upon
the actions of the members of the communities within the watershed.
9.1 Objective of the Education Program
The objective of the PROGRAM is to explain the information contained in the SWSPP, and to
educate the communities to the ways they can contribute to protecting the environment within the
Watershed, and hence protect the surface water supply. Interviews with public officials were
conducted to identify and develop ideas, functional objectives, and educational messages in regard to
surface water supply protection.
The PROGRAM is designed to educate the public and provide the local communities with information
to:
x allow informed input into decisions about water supply protection;
x recognize existing and potential threats to the surface water supply; and
x promote activities that minimize the release of contaminants within the Watershed.
This PROGRAM incorporates the results of discussions conducted on March 27 and 29, 2001, with
public officials from Cohasset, Situate, Norwell and Hingham, Massachusetts who met voluntarily with
representatives from Norfolk Ram Group, LLC and Common Sense Environmental. At the meetings,
a draft of the SWSPP and the PROGRAM were discussed and comments solicited regarding the best
methods to identify and develop ideas, functional objectives, and educational messages in regard to
surface water supply protection. Each attendee was invited to submit comments on the SWSPP and
the PROGRAM, and interested parties who were not able to attend the meetings were encouraged to
send in their comments. In general, interviewees expressed the following issues set forth below.
9.2 Implementation
Meeting attendees suggested that one of the objectives of the PROGRAM should be to clearly
explain how the environmental condition of the Watershed affects each individual’s quality of life. The
involvement of Conservation Commissions, Planning Boards, Watershed groups, Boards of Health
and Departments of Public Works was identified as beneficial to helping the Water Department
implement the SWSPP.
Meeting attendees suggested including the Weir River Watershed committee, the Straights Pond
Committee, individuals on the Hingham Conservation Commission contact list, the Massachusetts
American Water Company, and the Groundwater Advisory Committee in the implementation of the
PROGRAM.
Meeting attendees suggested that all interested representatives from all the communities within the
Watershed review the draft SWSPP simultaneously. Cohasset Town Hall after 5 p.m. was suggested
as an ideal meeting place.
9.3 Public Outreach and Education
The following suggestions are offered as means to inform and educate the public:
1. Post a page at the town websites that provides information about the Watershed and the
SWSPP.
2. Periodically send email and mail informational fact sheets about the Watershed and the
SWSPP to businesses and residents.
3. Include watershed information with water invoices.
4. Dispense information through science classes in the local schools.
5. Provide exhibits at town events such as foot races, the farmer's market and beach cleanups to
share information with stakeholders.
6. Other means include publishing information in the Mariner,Health Notes, the Elder Affairs
Newsletter, Cohasset Revitalization mailings, and Garden Club mailings. Evaluate the
potential for securing grant money for periodic news releases through state-funded Technical
Assistance Grants (TAG).
Based on interviews with Town officials, there are no language barriers in the watershed
communities.
9.4 Intercommunity Partnership
The success of the SWSPP requires mutual support among the Watershed communities. Therefore,
a Watershed Team should be developed consisting of at least one town official from each of the
Watershed communities. The purpose of the Watershed Team would be to have a forum to present
issues, address concerns, and foster communication and cooperation between the Watershed
communities with the common goal of protecting the Watershed and implementing the SWSPP.
9.5 SWSPP Information
Activities similar to those described below and included in Table 9-1, will enable Town officials and
interested community members to become informed about the Watershed and the SWSPP, have the
opportunity to express their concerns, obtain satisfactory answers to their questions, and make
recommendations regarding appropriate agency responses.
Prepare and distribute fact sheets. A Comment Survey Form was prepared and distributed to
interested parties and interviewees during the discussions forum conducted in March 2001. The
Comment Survey Form provided a brief description of the purpose of the SWSPP, described the
location of the Watershed communities within the Watershed, and provided an overview of the next
steps of the SWSPP. The Comment Survey Form also included information regarding the information
repositories discussed below. Additional fact sheets may be prepared and distributed as significant
developments occur, such as any additional findings and developments as they relate to the
implementation of the SWSPP in the future.
Establish and maintain information repositories. Two information repositories have been
established in the Watershed: one at the Paul Pratt Memorial Library located at 106 South Main
Street in Cohasset, and a second one at the Scituate Public Library located at 85 Branch Street, in
Scituate. The repositories will receive key information about the SWSPP, including work plans, fact
sheets, the SWSPP report, and other documents as appropriate.
Develop and maintain an internet web page. A surface water supply web page should be
developed that could be linked to town web pages and provide bulletin board and email/contact
information to interested parties. The SWSPP should be posted at the web page as well as
information updates, results from water quality testing, results from limnological studies, etc.
Develop a mailing/e-mail list. An e-mail list should be developed that would include names and
addresses of relevant federal, state and local officials and group representatives. This list may be
expanded as time goes on to include the names and addresses of other interested parties.
Opportunities to be included in the mailing list could be provided during community education and
public information meetings.
School presentations. Exhibits and presentation material for schools could be prepared to educate
student of the significance of the surface water supply, threats of contamination, and preventive
measures they can take to preserve this resource for future generations.
Presentations at community interest group meetings. Watershed information could be presented
to local officials and community interest groups at community meetings, which might encourage
attendees to become involved in actively promoting and protecting the Watershed. An excellent
source for Watershed Protection literature and presentation materials can be found at the Center for
Watershed Protection, Ellicott City, Maryland (www.cwp.org).
Informational articles for newspapers and periodicals. Informational articles could be published
in newspapers and periodicals discussing current issues regarding the surface water supply.
Inter-Community Meetings. Meetings with officials and the public could be conducted periodically to
provide a forum for communicating significant new information related to Watershed issues.
10.0 SUMMARY OF RECOMMENDATIONS
10.1 General
As noted in the Introduction to this report, the SWSPP is intended to create a starting point for
watershed protection, education, and management as a dynamic process going forward. Towards
this end, this report has presented numerous recommendations for future action. This final section of
the report provides a summary compilation of the SWSPP recommendations, and offers a
prioritization for implementing these recommendations based on the relative importance of each
recommendation to watershed protection. In short, the relative priority for implementing each
recommendation presented here is based upon a current day, subjective assessment of need, which
is expected to change over time. As this report is revisited in the future, a key objective should be a
re-assessment of the implementation schedule for SWSPP recommendations. This re-assessment
should include identifying recommended actions that have been accomplished, re-defining
recommended actions in light of changing conditions and additional information, and identifying new
areas where additional focus is required.
The recommendation actions developed in this report are summarized below and in Table 10-1.
They are grouped under several major categories, which are in general order of priority, the following:
Group A Watershed Monitoring and Assessment;
Group B Stormwater and Non-Point Source Pollution Controls;
Group C Septic System and Other Point Source Pollution Controls;
Group D Land Use Bylaws, Management, and Enforcement Funding;
Group E Open Space Acquisition and Conservation Restrictions; and
Group F Watershed Management.
For each recommendation, a proposed “Action Partner” is identified in Table 10-1. This entity is
considered the best advocate for implementing the recommendation. It is also important to designate
a oversight entity and a “Lead Person” for the overall coordination and implementation of the plans
and recommendations in this SWSPP. It is suggested the best oversight entity would be the
Cohasset Board of Water Commissioners with the Chairman, as the Lead Person. A proposed
schedule for implementing the recommendations is included in Table 10-2. Regarding staffing
requirements for implementing the recommendations listed in Tables 10-1 and 10-2: It is anticipated
that the Cohasset Water Commission will outsource (to consultants) many of the major action items
that are recommended for implementation within the first three year planning period. To date, the
Commission has utilized a Contract Operator for operation of the water plant and distribution system.
The Commission should consider modifying their existing contract with the Contact Operator to
include hiring a Water Supply Protection Coordinator. This coordinator should report to the Board of
Water Commissioners and be responsible for implementing and updating the SWSPP, either
performing the work directly, or accomplishing the action items through the coordinated use of
consultants. If modifying the Contract Operator agreement is not feasible, then an alternative would
be for the Commission to hire such a Water Supply Protection Coordinator directly.
Report Section ReferenceRecommended Action Action Partner(s)ProposeImplementSchedulA**Watershed Monitoring and Assessment2.3 Establish Watershed Partnership Cohasset Water Commissioners 20022.4 Revisit and Update SWSPP Cohasset Water Commissioners 20052.1 Assess Watershed Tributaries and Zone A Limits Cohasset Water Commissioners 20024.2 Long Term Sampling and Testing Cohasset Water Commissioners 20026.5 Limnology and Water's Edge Study Cohasset Water Commissioners 20023.1 Periodic Review of 21-E Sites Status Cohasset Water Commissioners Ongoing Qu3.5 Monitor Bedrock Wells Cohasset Water Commissioners Ongoing Qu3.6 Install Overburden Well Below Norfolk Conveyor SiteCohasset Water Commissioners2002B Stormwater and Non-Point Source Pollution Controls4.1 Stormwater BMP Controls in Cohasset Cohasset Water Commissioners 2002 - 205.9 Mapping Cohasset Water Commissioners 20025.1 Feasibility Study Cohasset Water Commissioners 20035.1 Design and Construct BMP Facilities Cohasset Water Commissioners 2003 - 203.14 Stormwater Management Plans Norwell & Scituate Boards of Health 2002 - 203.15 Phase II Stormwater Management Program Boards of Health 20035.7 Designate No-Salt Zones()ConsCom 20025.13 Lawn Care Management Programs Health 20033.25 Herbicide Application in Right-of-WaysCohasset Water CommissionersAnnual ReC Septic System and Other Point Source Pollution Controls3.19 Zone A Protections Cohasset Water Commissioners 2002 - 203.18 Sewer System Expansion Cohasset Water Commissioners 20043.16 Protections for Unnamed Stream in Scituate Scituate Board of Health 20033.17 Wastewater Management Plans Boards of Health 20035.6 Older Septic Systems Within Zone A Cohasset, Norwell & Scituate Boards of Health 2003 - 203.17 Septic System Instruction Boards of Health 20023.22 Water Treatment Plant SludgeCohasset Water Commissioners2004 - 20TABLE 10-1SUMMARY OF RECOMMENDATIONS
ReportSectionReferenceRecommended Action Action Partner(s)Proposed Implementation Schedule*D Land Use Bylaws, Management, and Enforcement Funding3.19 Zone A Restrictions, Special Permit Controls, Funding Water Commissioners and Town Meeting 2002 - 20033.13 Water Resources Protection Districts BylawsWater Commissioners 20033.28 Inter-community / Intra-community Cooperation Zoning Boards 2002 - 20035.5 Potential ACEC Areas Conservation Commissions 20045.14 Commercial Lawn Care Notification EnforcementHealth 2002 - 20037.2 Cohasset Master Plan Reference to SWSPPCohasset Water Commissioners and Town Meeting2003E Open Space Acquisition and Conservation Restrictions5.1 Developable Land Within Zone A/B Areas Cohasset Water Commissioners 2002 - 20045.2 Town-Owned Land (Research, Improve Controls) Cohasset Water Commissioners 2002 - 20045.3 Undevelopable Land (Research, Improve Controls) Cohasset Water Commissioners 2005 - 20075.4 "Owner Unknown" Land (Research, Improve Controls) Cohasset Water Commissioners 2008 - 20097.1 Deeds for Existing Open SpaceTown Clerks2010 - 2012F Watershed Management2.2 Hydrological Assessment Cohasset Water Commissioners 2002 - 20033.26 Non-Hemlock Confer Trees DPWs 20023.3 Geese and Other Nuisance Wildlife Cohasset Water Commissioners 20025.2 Municipal Land UsesDPWs 20025.15 Management Plan for Town-Owned Lands DPWs 20036.1 Fence Installation - Lily Pond DPWs 20026.2 Fence Repair, Installation - Aaron River Reservoir DPWs 20023.29 SignsCohasset Water Commissioners & DPWs 20026.3 Walking Trail - Aaron River Reservoir Cohasset Water Commissioners 20043.24 CHL Landfill NPDES Permit Cohasset Water Commissioners 20023.27 Fertilizers and Manure Boards of Health 20037.3 Proposed Prohibited Land Uses Boards of Health 20038.1 Emergency Response TrainingFire Departments2003*See Table 10-2 for more detail on implementation schedulesTABLE 10-1SUMMARY OF RECOMMENDATIONS
TABLE 10-2 IMPLEMENTATION SCHEDULE FOR RECOMMENDATIONSRept. RecommendationTIME FROM INCEPTION OF PROJECT (by Quarter Year Periods)Ref. Description2002 2002 2003 2003 2003 2003 2004 2004 2004 2004 2005 2005 2005 2005 2006 2006 2006 2006 2007 2007 2007 2007 20082Proposed Time Period to Complete (*) 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1stA Watershed Monitoring and Assessment2.3 Establish Watershed Partnership2.4 Re-visit and Update SWSPP2.1 Assess Watershed Tributaries and Zone A Limits4.2 Long Term Sampling & Testing. XRe-assess sampling and testing program6.5 Limnology and Water’s Edge Study3.1 Periodic Review of 21-E Sites Status 3.5 Monitor Bedrocks Wells XRe-assess sampling and testing program3.6 Install Overburden Well S.E. of Norfolk Conveyor SiteB4.1 Stormwater BMP controls in CohassetX3rd Year Review 5.9 Mapping.XX5.1 Feasibility studyX5.1 Design & Construct BMP FacilitiesXXXXX3.14 Stormwater Management Plans (Norwell, Scituate)X3rd Year Review 3.15 Phase II Stormwater Management Program Compliance5.7 Designate No-salt zones5.13 Lawn Care Management ProgramsX3rd Year Review 3.25 Herbicide Application in Right-of-WaysC3.19 Zone A ProtectionsX3rd Year Review 3.18 Sewer System ExpansionX3rd Year Review 3.16 Protections for Unnamed Stream in Scituate3.17 Wastewater Management PlansX3rd Year Review 5.6 Older Septic Systems Within Zone AX3rd Year Review 3.17 Septic System Instruction3.22 Water Treatment Plant SludgeYear 3 Year 4 Year 5 Year 6Stormwater and Non-Point Source Pollution ControlsSeptic System and Other Point Source Pollution ControlsYear 1 Year 2
TABLE 10-2 IMPLEMENTATION SCHEDULE FOR RECOMMENDATIONSRept. RecommendationRef. Description2007 2007 2008 2008 2008 2008 2009 2009 2009 2009 2010 2010 2010 2010 2011 2011 2011 2011 2012Proposed Time Period to Complete (*) 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1stA Watershed Monitoring and Assessment2.2 Hydrological Assessment2.3 Establish Watershed Partnership2.4 Re-visit and Update SWSPP2.1 Assess Watershed Tributaries and Zone A Limits4.2 Long Term Sampling & Testing. 6.5 Limnology and Water’s Edge Study3.1 Periodic Review of 21-E Sites Status 3.5 Monitor Bedrocks Wells 3.6 Install Overburden Well S.E. of Norfolk Conveyor SiteB Stormwater and Non-Point Source Pollution Controls4.1 Stormwater BMP controls in CohassetX3rd Year Review X3rd Year Revie5.9 Mapping.5.1 Feasibility study5.1 Design & Construct BMP Facilities3.14 Stormwater Management Plans (Norwell, Scituate)X3rd Year Review X3rd Year Revie3.15 Phase II Stormwater Management Program Compliance5.7 Designate No-salt zones5.13 Lawn Care Management ProgramsX3rd Year Review X3rd Year Revie3.25 Herbicide Application in Right-of-WaysC Septic System and Other Point Source Pollution Controls3.19 Zone A ProtectionsX3rd Year Review X3rd Year Revie3.18 Sewer System Expansion3.16 Protections for Unnamed Stream in Scituate3.17 Wastewater Management PlansX3rd Year Review X3rd Year Revie5.6 Older Septic Systems Within Zone AX3rd Year Review X3rd Year Revie3.17 Septic System Instruction3.22 Water Treatment Plant SludgeYear 10Year 6 Year 7 Year 8 Year 9
TABLE 10-2 IMPLEMENTATION SCHEDULE FOR RECOMMENDATIONSRept. RecommendationTIME FROM INCEPTION OF PROJECT (by Quarter Year Periods)Ref. Description2002 2002 2003 2003 2003 2003 2004 2004 2004 2004 2005 2005 2005 2005 2006 2006 2006 2006 2007 2007Proposed Time Period to Complete (*) 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2ndD Land Use Bylaws, Management and Enforcement Funding3.19 Zone A Restrictions, Special Permit Controls, Funding 3.13 Water Resources Protection Districts BylawsXAnnual Review XAnnual Review X3rd Year Review 3.28 Inter-community / Intra-community CooperationX3rd Year Review 5.5 Potential ACEC Areas5.14 Commercial Lawn Care Notification Enforcement7.2 Cohasset Master Plan Reference to SWSPPX3rd Year Review E Open Space Acquisition and Conservation Restrictions5.1 Developable Land Within Zone A/B Areas5.2 Town-Owned Land (Research, Improve Controls)5.3 Undevelopable Land (Research, Improve Controls)5.4 "Owner Unknown" Land (Research, Improve Controls)7.1 Deeds for Existing Open SpaceFWatershed Management2.2Hydrological Assessment3.26 Non-Hemlock Confer TreesXOngoing Effort3.3 Geese and Other Nuisance WildlifeXOngoing Effort5.2 Municipal Land UsesXAnnual Review XAnnual Review XAnnual Review X3rd Year Review 5.15 Management Plan for Town-Owned LandsX3rd Year Review 6.1 Fence installation – Lily Pond6.2 Fence Repair, Installation - Aaron River Reservoir3.29 Signs (in Cooperation with DEM on State Land)6.3 Walking Trail - Aaron River Reservoir3.24 CHL Landfill NPDES Permit Also check for compliance per EPA renewal schedule3.27 Fertilizers and Manure7.3 Proposed Prohibited Land UsesX3rd Year Review 8.1 Emergency Response TrainingX3rd Year Review Year 3 Year 4 Year 5Year 1 Year 2
TABLE 10-2 IMPLEMENTATION SCHEDULE FOR RECOMMENDATIONSRept. RecommendationRef. Description2007 2007 2008 2008 2008 2008 2009 2009 2009 2009 2010 2010 2010 2010 2011 2011 2011 2011 2012 20Proposed Time Period to Complete (*) 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2D Land Use Bylaws, Management and Enforcement Funding3.19 Zone A Restrictions, Special Permit Controls, Funding 3.13 Water Resources Protection Districts BylawsX3rd Year Review X3rd Year Review 3.28 Inter-community / Intra-community CooperationX3rd Year Review X3rd Year Review 5.5 Potential ACEC Areas5.14 Commercial Lawn Care Notification Enforcement7.2 Cohasset Master Plan Reference to SWSPPX3rd Year Review X3rd Year Review E Open Space Acquisition and Conservation Restrictions5.1 Developable Land Within Zone A/B Areas5.2 Town-Owned Land (Research, Improve Controls)5.3 Undevelopable Land (Research, Improve Controls)5.4 "Owner Unknown" Land (Research, Improve Controls)7.1 Deeds for Existing Open SpaceFWatershed Management3.26 Non-Hemlock Confer Trees3.3 Geese and Other Nuisance Wildlife5.2 Municipal Land UsesX3rd Year Review X3rd Year Review 5.15 Management Plan for Town-Owned LandsX3rd Year Review X3rd Year Review 6.1 Fence installation – Lily Pond6.2 Fence Repair, Installation - Aaron River Reservoir3.29 Signs (in Cooperation with DEM on State Land)6.3 Walking Trail - Aaron River Reservoir3.24 CHL Landfill NPDES Permit3.27 Fertilizers and Manure7.3 Proposed Prohibited Land UsesX3rd Year Review X3rd Year Review 8.1 Emergency Response TrainingX3rd Year Review X3rd Year Review * See report per section reference number listed for more detailed descriptions of recommendations. Also, see Table 10-1.Year 10Year 6Year 7Year 8Year 9
Partnership (Recommendation 2.3) The Town of Cohasset should establish a partnership with the
other Watershed communities based upon the common goal of protecting the surface water supply.
The intent of this partnership should be to create a forum for the discussion of Watershed protection
issues, to identify the appropriate action partner(s) to implement Watershed initiatives and to
establish specific timeframes for implementing the initiatives developed in this SWSPP. In this
regard, the South Coastal Watershed Team could help with other Watershed Communities. The
Cohasset Town Planner has indicated several representatives from Cohasset, Scituate and Norwell
are active participants of the Team. The technical expertise of the Team coordinator and various
state representatives could be instrumental in organizing the partnership and providing technical
assistance.
Revisit and Update SWSPP (Recommendation 2.4) The Cohasset Board of Water Commissioners
should revisit this SWSPP at least every three (3) years to evaluate and revise the recommendations
and the implementation schedule for recommendations, and to identify achievements and areas
where additional efforts should be focused.
10.2 Watershed Monitoring and Assessment (Group A)
The first and most important priority for watershed management is the monitoring of water quality and
monitoring of known potential threats within the Watershed. This includes data gathering and careful
interpretation of water quality data, and the monitoring of “potential threats” sites for changes in
activity, contaminant levels and contaminant pathways to the surface water supply until such time that
the sites are successfully remediated and/or they no longer threaten water quality within the
Watershed. The following are recommended as Watershed assessment and monitoring activities.
Assess Watershed tributaries and Zone A limits (Recommendation 2.1). The Cohasset Board of
Water Commissioners should determine the extent and direction of flow in the potential tributary
stream to Brass Kettle Brook located west of the wetland, and the extension of the South Swamp
tributary to the Aaron River Reservoir identified by the First Herring Brook Initiative, and the existence
of channel flow through the bordering wetlands located south of Bound Brook Pond in the town of
Norwell, which may include some of Burnt Plain Swamp. If these areas are tributary a significant
extension of the Zone A may be appropriate.
Long term sampling & testing (Recommendations 3.21, 4.2, 4.3, 6.6). Although some water
quality testing and monitoring of land use activities within the Watershed have been performed over
the past few years, the first priority recommendation is for the Cohasset Board of Water
Commissioners to implement the long term sampling & testing program as presented in this report at
Section 4-4. The proposed sampling locations are noted on Map 1b “Potential Threats to the
Watershed” and the proposed testing program summarized in Table 4-3. The Cohasset Board of
Water Commissioners should implement the long-term sampling plan to monitor nutrient
concentrations in Lily Pond and Aaron River Reservoir and all tributaries. The sampling results
should be assessed by an experienced limnologist to update the Town on the state of eutrophication
of Lily Pond and Aaron River Reservoir.
Limnology and water’s edge study (Recommendation 6.5). The Town of Cohasset should
conduct a limnology and water’s edge study of Lily Pond and Aaron River Reservoir to include both a
diagnostic and feasibility evaluation. An assessment of the trophic state of both the pond and the
reservoir based upon the seasonal measurement of chemical constituents, and the relationship
between the makeup of the water’s edge and nutrient loading should be components of the study.
Periodic Review of 21E sites status. The Cohasset Board of Water Commissioners should
periodically review the progress of response actions conducted at the state 21E sites listed below so
that potential impacts to the surface water supply can be assessed. This review should continue until
1) these sites have been determined by DEP as no longer posing a threat to water quality within the
Watershed, and/or 2) the ongoing long term sampling & testing program has determined that impacts
from these sites is insignificant and unlikely to become significant.
1) Hingham Training Annex Disposal Site (Recommendations 3.1, 3.2);
2) Former Beechwood Dump (Recommendations 3.3, 3.4);
3) Former Norfolk Conveyor Site (Recommendations 3.5, 3.6);
4) Former Burning Ground (Recommendations 3.7, 3.8);
5) Cohasset Heights Landfill (Recommendations 3.9, 3.10, 3.20); and
6) Former Clapp Landfill (Recommendations 3.11, 3.12).
Monitor Bedrock Wells (Recommendations 3.5, 3.9). The Cohasset Board of Water
Commissioners should continue to monitor the bedrocks wells on a quarterly basis, until the SWSPP
is revisited (after three years) at which time the need to monitor can be reevaluated, and periodically
review the progress of response actions conducted at the former Norfolk Conveyor site so that
potential impacts to Lily Pond can be assessed. Install overburden well between Norfolk Conveyor
site and Lily Pond.
Install Overburden Well Between Norfolk Conveyor Site & Lily Pond (Recommendations 3.6 and
3.10) The Cohasset Board of Water Commissioners should consider evaluating the feasibility of
installing overburden-monitoring wells in the depositional sands and gravels of the former or existing
wetlands located between the former Norfolk Conveyor site and Lily Pond. The geology of these
wetlands are areas of greatest soil thickness consisting of deposits of gravel, sand and/or silts with
relatively high hydraulic conductivities, and could potentially serve as a pathway for impacted
groundwater to Lily Pond.
10.3 Stormwater and Non-Point Source Pollution Controls (Group B)
Aside from the need to continue gathering data on watershed water quality, this is the single greatest
need and priority for protecting the surface water supply. This priority is based on 1) the reported
eutrophic to hyper-eutrophic state of both Lily Pond and the Aaron River Reservoir, 2) the known
presence of multiple discharges of uncontrolled or poorly controlled stormwater into Lily Pond and
into the tributaries to both the pond and the reservoir, and 3) the evidence gathered to date on the
water contamination that can be attributed to stormwater and non-point source impacts (phosphorus,
nitrogen, TSS, and metals) based on water quality testing to date. There are several recommended
actions under this category which are listed in summary form below:
Stormwater BMP controls in Cohasset (Recommendation 4.1). Stormwater Best Management
Practice (BMP) controls should be implemented at roads within the Zone A of the Watershed. Also
the water quality parameters with deviations from normal found at the aforementioned locations
should be closely observed over the next few quarterly sampling rounds to determine if these
deviations in water quality are indicative of long-term problematic water quality issues or merely
seasonal fluctuations.
x Mapping (Recommendation 5.9). The Town of Cohasset Planning Department has
submitted an application to the DEP for a Watershed Improvement Grant. The grant money as
well as matching funds from the town would be put towards a town-wide mapping effort to
located and describe the storm water drainage system in Cohasset. The stormwater mapping
project would serve as a critical component in analyzing the Watershed, identifying non-point
sources of contamination within the Watershed, and provide sustainable protection of the
surface water supply into the future. Continued joint efforts between the Cohasset Board of
Water Commissioners, Board of Health, DPW, and Planning Board to accomplish stormwater
drainage system mapping on a town-wide basis should be pursued. A town-wide GIS, which
would include storm drain system mapping, requires the participation of many town
departments to ensure that relevant data remains accurate and up to date once initial mapping
is completed. If funds are limited, mapping Zone A and Zone B areas and threatened coastal
and wetland areas should be pursued as an immediate priority.
x Feasibility study (Recommendation 5.10). There are critical areas identified as tributaries to
Lily Pond and the Aaron River Reservoir that should be addressed as a priority. The feasibility
of installing stormwater treatment systems along Route 3A where it comes in close proximity to
Peppermint Brook and along King Street where drainage is tributary to Lily Pond and
especially within the Zone A should be evaluated. Following the feasibility study, treatment
systems should be designed and constructed to capture oil and other petroleum products to
prevent their discharge into Peppermint Brook.
x Design and Construct BMP Facilities (Recommendation 5.10). Based upon feasibility
study, design and construct BMP facilities including roadway spill collection systems along
Route 3A, along King Street where drainage is tributary to Lily Pond and especially within the
Zone A ,and other critical areas tributary to Lily Pond.
Stormwater management plans (Recommendation 3.14). It is reported the Towns of Norwell and
Scituate are currently developing stormwater management plans. Best Management Practices
should be identified and implemented immediately for the sections of road identified as posing a
significant threat to the surface water supply. At a minimum, no-salt zones should be designated
along the sections of roads with drainage basins that discharge directly to the surface water supply.
The town Planning Boards could codify in their regulations stormwater controls as part of the approval
process for site plans, subdivisions and proposed creation of impervious areas. At a minimum these
regulations should comply with the DEPs Best Management Practices set forth in their Stormwater
Management Policy.
Phase II Stormwater Management Program (Recommendation 3.15). The Watershed towns
should comply with the DEP’s Phase II Stormwater Management Program by the required deadline in
2003. The Cohasset Board of Water Commissioners should request the opportunity to follow and
comment on the communities’ progress.
Designate no-salt zones (Recommendations 5.7, 5.8). The Town of Cohasset should request that
the MHD designate the area of Route 3A where it is tributary to Peppermint Brook a no-salt zone.
The Town of Norwell should designate Mt. Blue Street and Mount Hope Street within the Zone B near
Bound Brook Pond no-salt zones.
Lawn care management programs (Recommendations 3.23, 5.13). The Cohasset Board of Water
Commissioners in partnership with Boards of Health in the Watershed communities should develop
and implement a Lawn Care Management Program for areas within the Zone A and all town-owned
properties. The plan should define areas where the application of lawn care chemicals is prohibited
such as within 200 feet of the surface water supply or tributaries, and establish recommended
application procedures and frequencies for areas within the Zone A and Zone B.
Herbicide application in right-of-ways (Recommendation 3.25). The Cohasset Board of Water
Commissioners should maintain close oversight of the application of herbicides in areas of right-of-
ways that are within the Zone A, and request in writing, advanced notice of any planned application of
herbicides within the Zone A and Zone B areas of the watershed, and an annual updated copy of the
utility company YOP.
10.4 Septic System and Other Point Source Pollution Controls (Group C)
Zone A protections (Recommendation 3.19). Implement Zone A zoning and non-zoning controls
through local bylaws and/or Board of Health regulations. The towns within the Watershed should
adopt zoning and non-zoning controls within the Zone A pursuant to 310 CMR 22.00, the Drinking
Water Regulations. (See Model Zone A Bylaw in Appendix B). In Cohasset, for proposed zoning
changes, the Cohasset Board of Water Commissioners should enlist the support of the Zoning
Advisory Committee, which is a sub-committee of the Planning Board.
Sewer system expansion (Recommendation 3.18). Continue to expand Cohasset municipal sewer
system with the goal of eliminating Zone A septic systems (1st priority) followed by systems within
Zone B areas (2nd priority). The towns of Cohasset and Scituate should extend the municipal sewer
into areas where residences with on-site septic systems are located within the Zone A.
Protections for South Swamp Tributary in Scituate (Recommendation 3.16). The Town of
Scituate should located/mapped and recognized for proper Title 5 setback requirements, filling and
dredging restrictions, Zone A prohibitions, and, if applicable Rivers Act buffer requirements the
extension of the South Swamp tributary to the Aaron River Reservoir identified by the First Herring
Brook Watershed Initiative.
Wastewater management plans (Recommendation 3.17). The Watershed communities should
encourage all towns within the Watershed to develop and implement Comprehensive On-Site
Wastewater Management Plans.
Older septic systems within Zone A areas (Recommendation 5.6). Cohasset, Norwell and
Scituate should determine if on-site septic systems located within Zone A areas fail to protect the
public health, safety and environment as required by Title 5 regulations and require system upgrades.
Cohasset should consider modifying their Storm Water Management Plan to include funding these
actions through the Septicredit program. Also, the towns should consider adopting regulations
possibly designating Septic System Management Districts where periodic inspections of septic
systems within the Zone A are mandated.
Septic system instruction (Recommendation 3.17). The occupants of residences within 400 feet
of the surface water supply or tributaries should be instructed as to the detrimental effect of
antiquated septic systems, disposal of chemicals via sinks or toilets and the benefits of using laundry
detergents that do not contain phosphates.
Water treatment plant sludge (Recommendations 3.22, 5.12). The Town of Cohasset should
evaluate the potential for off-site disposal of the treatment sludge pursuant to 310 CMR 32.00, the
Land Application of Sludge and Septage regulation. Tying sanitary and wastewater discharges from
the water treatment plant into the existing municipal sewer system along King Street should be
evaluated.
10.5 Land Use Bylaws, Management and Enforcement Funding (Group D)
Zone A Restrictions, Special Permit Controls, Funding (Recommendation 3.19). (See Zone A
protections noted above.) Implementation of the Zone A protections discussed above are critically
important for protecting the source water supply from septic systems and other point sources of
contamination. These protective restrictions can be implemented through town-approved upgrades to
the local water resource protection district bylaws. In Cohasset, for proposed zoning changes, the
Cohasset Board of Water Commissioners should enlist the support of the Zoning Advisory
Committee, which is a sub-committee of the Planning Board. Another more direct pathway to
consider for implementation is for the local Boards of Health to amend their existing rules and
regulations. This can be done without town meeting approval, however, consultation with local town
counsel is advised. Proper funding of the Board of Health and/or town inspectional services is also
critically important to ensure proper implementation and endorsement of bylaw protections. (See
Model Zone A Bylaw in Appendix B.)
Water Resources Protection District bylaws (Recommendations 3.13, 7.6). The Watershed
communities in cooperation with the Cohasset Board of Water Commissioners, should continue to
implement and periodically review and update where appropriate their Water Resources Protection
Districts bylaws. The Cohasset Board of Water Commissioners should request the opportunity to
review the community bylaws or proposed changes and make recommendations towards furthering
the protection of the surface water supply. Also, all towns within the Watershed should incorporate
the requirements of the Drinking Water regulation to the Zones A, B, and C of the surface water
supply, pursuant to 310 CMR 22.20B
Inter-community and intra-community cooperation (Recommendation 3.28). The Watershed
communities should allow officials from each town the chance to review and comment on zoning
variances or special permits for proposed future development. To the best of its ability, town officials
in the town where the zoning variances or special permits apply should incorporate the comments of
the other Watershed town officials into the approval process.
Commercial Lawn Care Notification Enforcement (Recommendation 5.14) The Cohasset Board
of Water Commissioners should work on partnership with the Board of health to properly fund and
implement the existing bylaw Article XIII Section (c) that applies to Commercial Lawn Care
notifications prior to pesticide/herbicide applications in the WRD.
Potential ACEC areas (Recommendation 5.5). The Watershed communities should identify
potential areas within the Watershed to nominate for ACEC status such as the South Swamp tributary
and associated wetland system watershed located north of Clapp Road in Scituate, as well as the
unique habitat and resource value of the South Swamp located south of Clapp Road and partly in the
Watershed.
Cohasset Master Plan Reference of SWSPP (Recommendation 7.2). Cohasset should include
the protection of the surface water supply as proposed in this SWSPP as a component of the town’s
master plan. Cohasset should include the protection of the surface water supply as a component of
the town’s master plan. The Growth and Development Committee has drafted a vision statement that
reads in part “Prudent planning and careful management of the town’s natural resources protect the
quality and quantity of the town’s waters – drinking water supply, streams, wetlands, and coastal
waters.” Moreover, water supply protection has emerged, via surveys and public meetings, as a key
concern and top priority. The master plan must balance a variety of issues and priorities as
expressed by various stakeholders during the process. The recommendations of the SWSPP should
be considered very carefully along with other top community priorities.
10.6 Open Space Acquisition and Conservation Restrictions (Group E)
Developable Land Within Zone A/B Areas (Recommendation 5.1) The Cohasset Board of Water
Commissioners should further evaluate (as to feasibility and priority) the developable land parcels
located within the Zone A areas (including developable parcels that abut parcels in Zone A); and then
pursue acquisition for open space, or restrictions for such parcels. The priority for plan years one
through three should be parcels in Zone A along Lily Pond, Aaron River Reservoir and tributaries
thereto; priority for plan years four through six should be parcels that abut parcels in the Zone A (for
the pond, reservoir and tributaries); and priority for years seven through ten should be Zone B parcels
closest to Zone A areas. The Commissioners should work cooperatively with existing town boards
such as the Open Space Committee and the Community Preservation Committee to share resources
and information regarding land acquisition priorities.
Town-owned land – research, improve controls (Recommendation 5.2). The Town of Cohasset
should investigate the deeds to town-owned land to the immediate north and northwest of Lily Pond,
and if necessary strengthen the protections to maximize surface water supply protection.
Undevelopable land – research, improve controls (Recommendation 5.3). The Cohasset Board
of Water Commissioners should consider parcels presently recorded as undevelopable within the
Zone A for possible Town Open Space acquisition or for securing protective conservation deed
restrictions (see Map 3).
“Owner unknown” land – research, improve controls (Recommendation 5.4). The Town of Cohasset
should evaluate the possibility of acquiring parcels located within or abutting the Zone A of Lily Pond
where the Assessor’s records indicate unknown ownership, (see Map 4).
Deeds for existing Open Space (Recommendation 7.1). The Watershed communities should
research the deeds for Open Space, which is protected by “something other than time” so that the
degree of protection is understood, and if necessary strengthen the protections to maximize surface
water supply protection.
10.7 Watershed Management (Group F)
Hydrological Assessment (Recommendation 2.2). The Cohasset Board of Water Commissioners
should conduct a hydrologic assessment to include a water balance evaluation, wetlands and wildlife
inventory and stream channel characterization. As part this assessment, at least five stream flow and
stage gauging stations should be constructed equipped with constant recording open channel flow
meters, and stream gages to measure stage. The proposed locations for the stations are at the
Aaron River downstream of the fish ladder (at Doane Street), at the upstream side of the BBCS, at
the upstream extent of Herring Brook where it meets Lily Pond, brass Kettle Brook at Lily Pond, and
Peppermint Brook at Lily Pond. Stream flow and stage data should be collected at each station over
the course of one year to establish baseline flow data from which to monitor changes going forward.
Non-hemlock conifer trees (Recommendation 3.26). The Towns of Cohasset, Hingham and
Scituate should plant, or encourage the planting (via education and/or a program to supply and plant
saplings) of non-hemlock conifer tree species in areas damaged by woody adelgid infestation within
50 feet of the Aaron River Reservoir or Lily Pond in order to reduce potential siltation of the water
bodies and maintain slope stability. This planting program may best be implemented through local
conservation commission efforts. The Cohasset Board of Water Commissioners should discuss such
a program with their local conservation commissioners.
Geese and other nuisance wildlife (Recommendations 3.30, 6.4). The Cohasset Board of Water
Commissioners should take steps to discourage geese and other nuisance wildlife from roosting near
Lily Pond. One method gaining in popularity is to employ the use of dogs such as the Border Collie.
These animals tirelessly pursue geese on the ground and provide a harmless threat that discourages
the geese from setting up roost. The dogs are available for sale through kennels that specifically train
them this purpose.
Municipal land uses (Recommendation 5.11). The Watershed communities should periodically
review municipal land uses in the Watershed to ensure that any activities that have the potential to
adversely impact the surface water supply are identified and addressed as necessary through site
improvements and/or facility management plans.
Management plan for town-owned lands (Recommendation 5.15). A written management plan
should be developed for town-owned land within the Watershed. This management plan should
include regular inspections to look for unauthorized activity, illegal dumping, obstructions to stream
flow, missing signs, and other maintenance needs.
Fence installation – Lily Pond (Recommendation 6.1). The Cohasset Board of Water
Commissioners should install a fence at Lily Pond near the water treatment plant to limit public
access at that location, and signs should be posted listing the recreational activities that are allowed
and prohibited.
Fences repair and installation – Aaron River Reservoir (Recommendation 6.2). The Cohasset
Board of Water Commissioners should repair the fence to the Aaron River Reservoir via Beechwood
Street, install a gate, and install public accommodations (i.e. stairs and/or ramps). Signs should be
posted listing the recreational activities that are allowed and prohibited.
Signs (Recommendation 3.29). The Cohasset Board of Water Commissioners should post signs at
the public access ways for both Lily Pond and the Aaron River Reservoir that indicate allowed and
prohibited activities within these water bodies.
Walking trail - Aaron River Reservoir (Recommendation 6.3). The Watershed communities
should develop a walking trail around Aaron River Reservoir that would serve to define and control
the specific areas the public can utilize. This walking trail should be set back from the edge of the
reservoir so as to provide a minimum 25-foot buffer zone. Trash containers placed at strategic
locations along the trail would help control trash in the area.
CHL Landfill NPDES permit (Recommendation 3.24). The Cohasset Board of Water
Commissioners should demand that the EPA order the CHL Landfill operator to obtain and keep
current a NPDES permit for the discharge of its landfill stormwater into the Lily Pond Watershed.
Fertilizers and manure (Recommendation 3.27). The Watershed communities should require that
all outdoor storage of fertilizers or manure be contained in weatherproof enclosures.
Proposed prohibited land uses (Recommendations 7.3, 7.4, 7.5). Cohasset should prohibit the
following land uses within the Zone A of the Watershed: commercial car/truck washes; dry-cleaning
establishments; metal plating, finishing, or polishing; chemical or bacteriological laboratories;
commercial photographic processing; commercial printing other than xerographic reproduction; self-
service laundries unless sewered; hotels or motels unless sewered; cabinet/furniture making
establishments; painting, wood preserving, and furniture stripping establishments; and electronic
circuit assembly facilities. The Cohasset Board of Water Commissioners should enlist the support of
the Zoning Advisory Committee, which is a sub-committee of the Planning Board when proposing
future zoning changes.
Norwell should prohibit the following land uses within the Zone A of the Watershed: cabinet/furniture
making establishments; painting, wood preserving and furniture stripping establishments; electronic
circuit assembly facilities; and outside storage of herbicides, pesticides, or fertilizer in amounts
exceeding normal household or agricultural use.
Scituate should prohibit the following land uses within the Zone A of the Watershed: non-sanitary
treatment/disposal works subject to 314 CMR 5.00; and the removal of soil within four feet of the high
groundwater elevation.
Emergency Response Training (Recommendation 8.1). Inter-community emergency response
training should be conducted on a routine basis in conjunction with local fire departments from the
Watershed communities to coordinate response activities that may be necessary to address potential
emergencies in each of the communities.
APPENDIX A
MAPS
Thematic Data Layers Portrayed on the GIS Maps
List of Assessor Parcels Categorized as Undeveloped Land by the Town of Cohasset
Assessor’s Office
Map 1a Land Use
Map 1b Potential Threats to the Watershed
Map 2 Protected Areas, Open Space, and Municipal Zoning
Map 3 Undevelopable Land Parcels
Map 4 Parcels of Unknown Ownership
Thematic Data Layers Portrayed On The GIS Maps
MAP 1a
1. Landuse
2. FEMA 100 Year Flood Zones
3. Zone A Surface Water Protection
4. Zone B Surface Water Protection
5. Zone C Watershed Boundary
6. Surface Hydrography
7. Wompatuck State Park
8. Roads
9. Public Water Supplies
10. Town Boundary
MAP 1b
1. Septic and Sewered Areas
2. Landuse
3. Landfills or Solid Waste Areas
4. 21-E sites
5. Underground Storage Tanks
6. Surface Water Sampling Points
7. Bedrock Monitoring Wells
8. Spills/Releases
9. NPDES Discharges
10. MHD Road Salt Storage Area
11. Surface Hydrography
12. Wetlands
13. Zone A Surface Water Protection Area
14. Zone B Surface Water Protection Area
15. Zone C Watershed Boundary Area
16. Roads
17. Town Boundary
18. Wompatuck State Park
MAP 2
1. Municipal Zoning
2. Open Space
3. Water Resources Protection Districts
4. Utility Corridors
5. U.S. Government, Hingham Annex
6. Certified Vernal Pools
7. Priority Sites of Rare Species Habitats
8. Zone A Surface Water Protection Area
9. Zone B Surface Water Protection Area
10. Zone C Watershed Boundary Area
11. Town Boundary
12. Roads
13. Surface Hydrography
MAP 3
1. Landuse (undeveloped land)
2. Zone A Surface Water Protection Area
3. Zone B Surface Water Protection Area
4. Zone C Watershed Boundary Area
5. Wetlands
6. Surface Hydrography
7. Wompatuck State Park
8. Town Boundary
MAP 4
1.Landuse (undeveloped land)
2. Zone A Surface Water Protection Area
3. Zone B Surface Water Protection Area
4. Zone C Watershed Boundary Area
5. Wetlands
6. Surface Hydrography
7. Wompatuck State Park
8. Town Boundary
List Of Assessor Parcels Categorized As Undevelopable Land
By The Town Of Cohasset Assessor’s Office
Map and Lot Map and Lot
41-027
41-032
41-110A
42-027
51-031
52-053
52-054
52-055
52-056
52-057
52-058
52-059
52-060
52-061
52-062
52-063
53-070
54-019
54-025
55-128
55-128
56-011
56-012
56-013
56-014
56-015
56-016
56-030
56-052
59-002
59-011
59-012
60-012
65-007
65-008
65-009
65-010
66-001
66-004
66-005
66-007
66-010
66-013
66-014
67-001
72-001
72-002
APPENDIX B
Supporting Documentation
· Land Use Pollution Potential Matrix
· DRAFT Land Use/Associated Contaminants Matrix
· Quality Assurance Project Plan
· Model Zone A Bylaw Revisions Proposed for Cohasset
· Inventory of Stormwater Drainage Systems Tributary to Lily Pond (Norfolk Ram Group memo
dated 04/02/02 including GIS Figures showing locations)
Massachusetts Department of Environmental Protection
Source Water Assessment Program
January 1999
Land Use Pollution Potential Matrix
Under the Source Water Assessment Program (SWAP), the State is required by EPA to create an inventory of
potential contamination sources and evaluate their likelihood to adversely impact source waters of public water
supplies. The table below, which will be used in this inventory effort, presents land uses and activities considered to
be significant potential sources of contamination to drinking water. Each land use has been ranked relative to its
threat to the water quality (high, moderate, low), considering the type of drinking water source (groundwater or
surface water). When looking for a particular potential pollution threat, all land use categories should be reviewed,
as some activities may overlap land use categories (i.e., pesticide use and storage), but may be listed under only one
category.
The ranking assigned to each of the land uses represents the relative risk it could potentially pose to a drinking water
source compared to other land uses in the assessment area. The threat assigned to a particular land use was based
on, but not limited to, the type and quantity of chemicals used or wastes generated by the business, and the behavior
and mobility of the pollutants in the soils and groundwater. The land uses considered potential contamination
sources are those facilities that typically use, produce, or store contaminants of concern, which, if managed improperly,
could find their way to a source of public drinking water. It is important to understand that a release may never occur from the
potential contamination source provided they are using best management practices (BMPs). If BMPs are in place, the actual risk posed
by the activity may be lower than the ranking presented in this matrix. Many potential contamination sources are regulated at the federal,
state and/or local levels, to further reduce the risk of a release.
The land use pollution potential ranking matrix was originally created from a compilation of numerous source
protection documents published in New England, and the combined field experience of DEP staff from the
Drinking Water Program, Bureau of Waste Site Cleanup and the Bureau of Waste Prevention1. In addition, the
advisory committees and other EOEA agencies provided significant input during the drafting of the matrices.
EPA has created a matrix which links land uses and the specific contaminants that may be associated with them.
DEP plans to post this matrix on its web site and make it widely available as soon as the final version is available
from EPA this winter.
References:
1 CCAMP, A Guide to Contamination Sources for Wellhead Protection, February 1989.
MA DEP/DWS, Watershed Resource Protection Self-Audit, May 8,1996.
NEIWPCC, Source Protection: A Guidance Manual for Small Surface Water Supplies In New England, March 1996.
EPA OTA, Protecting the Nation’s Groundwater from Contamination, October 1984.
MA DEP/DWP, Making Wellhead Protection Work in Massachusetts: A Guide for Developing Local Groundwater
Protection Controls, December 1997.
EPA/ORD, Environmental Planning for Small Communities: Guide for Local Decision-Makers, September 1994.
LAND USE THREAT
AGRICULTURAL Groundwater Surface Water
Dairy farms M H
Fertilizer storage or use M M
Forestry Operations L M*
Livestock Operations M H
Landscaping M M
Manure spreading or storage H H
Nurseries M M
Pesticide storage or use H H
Slaughterhouses M H
*Threat is low with an approved Chapter 132 forest management plan.
COMMERCIAL Groundwater Surface Water
Airports H M
Auto repair shops H M
Boat yards/builders H H
Bus and Truck terminals H M
Car washes L L
Cemeteries M L
Dry cleaners H M
Funeral homes L L
Furniture Stripping and
Refinishing
H M
Gas/service stations H M
Golf courses M M
Junk yards and Salvage
yards
H H
Laundromats L L
Medical facilities M L
Nursing homes L L
Paint shops H M
Photo processors H M
Printer and Blueprint shops M M
Railroad tracks and Yards H H
Repair shops
(engine, appliances, etc.)
H M
Research laboratories M M
Rust proofers H H
Sand and Gravel
mining/washing
M M
INDUSTRIAL Groundwater Surface Water
Asphalt, Coal tar, and
Concrete plants
M M
Chemical manufacture or
storage
H H
Electronics/electrical
manufacture
H M
Electroplaters H M
Food processors L L
Foundries or Metal
fabricators
H M
Fuel oil distributors H H
Gasification plants
(oil or coal)
M H
Hazardous waste storage,
treatment and recycling
H H
Industrial lagoons and pits H H
Hazardous materials storage H H
Industrial parks H H
Jewelry or Metal plating H M
Machine/metalworking shops H M
Metal and Drum
cleaning/reconditioning
H H
Nuclear power plants H H
Paper manufacture H H
Pharmaceutical manufacture H H
Plastic manufacture H H
RCRA TSDF facilities H H
Storage facilities
(petroleum and chemical)
H H
Tanneries H H
Textile manufacture H H
Wood preserving facilities M M
RESIDENTIAL Groundwater Surface Water
Fuel oil storage M M
Lawn care/Gardening M M
Septic systems/cesspools M M
MISCELLANEOUS Groundwater Surface Water
Aboveground storage tanks M M
Aquatic wildlife L H
Clandestine dumping H H
Combined sewer overflow L H
Composting facilities L M
Dredge disposal facilities M H
Fire training facilities M M
Fishing/boating L M
Landfills and Dumps H H
Land application of sewage
sludge
M M
Large quantity hazardous
waste generators
H H
Military facilities
(past and present)
H H
NPDES locations L H
Pipelines
(oil and sewer)
M M
Prisons M M
Road and Maintenance
depots
M M
Schools, colleges and
universities
M M
Small quantity hazardous
waste generators
M L
Snow dumps M M
Stormwater drains/
Retention basins
L H
Tire dumps M M
Transmission line right of
ways
L H
Transportation corridors M H
Underground storage tanks H M
Utility substation
transformers
L M
Very small quantity
hazardous waste generators
L L
Waste incinerators M H
Waste transfer stations M M
Wastewater treatment plants M H
Water treatment sludge
lagoon
M L
NOTE: These rankings may be revised in the future if additional information indicates that the current ranking
is inappropriate.
H = High
M = Moderate
L = Low
Massachusetts Department of Environmental Protection
Source Water Assessment Program
February 1999
DRAFT Land Use/Associated Contaminants Matrix
AGRICULTURAL Contaminants of Concern
Livestock Operation MIC/IOC
nitrate
nitrite
Dairy Farms MIC/IOC
nitrate
nitrite
lindane
methoxychlor
2,4-D
glyphosate
dicamba
EPTC
Fertilizer Storage or Use IOC
cyanide
nitrate
nitrite
fluoride
Forestry Operations VOC
turbidity
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
anthracene
lindane
Manure Spreading or
Storage
MIC/IOC
nitrate
nitrite
Nurseries SOC
methoxychlor
carbaryl
dimethoate
disulfoton
Pesticide/Herbicide Storage
or Use
SOC
alachlor
aldicarb
aldicarb sulfoxide
aldicarb sulfone
atrazine
carbofuran
2,4 -D
lindane
methoxychlor
diquat
endothal
glyphosate
hexachlorobenzene
hexachlorocyclopentadiene
oxamyl
picloram
simazine
butachlor
carbaryl
dicamba
3-hydroxycarbofuran
methomyl
metolachlor
metribuzin
propachlor
endosulfan
acetochlor
alachlor ESA
atrazine-desethyl
cyanazine
diazinon
dimethoate
disulfoton
diuron
fonofos
linuron
terbufos
terbacil
molinate
2,4,6 trichlorophenol
methyl bromide
prometon
nitrobenzene
acetone
PCE
TCE
xylene
1,1,1,2 tetrachloroethane
1,3 dichloropropene
m-dichlorobenzene
nitrobenzene
chlorodibromomethane
trichloromethane
chloromethane
bromomethane
selenium
Slaughterhouses MIC/IOC
nitrate
nitrite
arsenic
COMMERCIAL Contaminants of Concern
Airports VOC/SOC/IOC
benzene
toluene
ethylbenzene
xylene
n-propylbenzene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
1,2,4 trimethylbenzene
1,3,5 trimethylbenzene
cumene
2,4-D
2,4,5-TP
dalapon
diquat
glyphopsate
carbon tetrachloride
o-dichlorobenzene
1,2 DCE
chlorobenzene
1,1,1 TCA
1,1 DCA
1,2 DCA
1,1,2,2 tetrachloroethane
PCE
TCE
methylene chloride
methoxychlor
heptachloroepoxide
endosulfan
cadmium
mercury
beryllium
nickel
phenol
bromobenzene
hexachlorobutadiene
Auto Repair Shops VOC/IOC/SOC
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1,2,3 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,I) perylene
chrysene
fluoranthene
fluorene
pyrene
phenol
chloroethane
bromobenzene
hexachlorobutadiene
Boat Yards/Builders VOC/SOC/IOC
toluene
benzene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1,2 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
phenol
bromobenzene
hexachlorobutadiene
Bus and Truck Terminals VOC/SOC/IOC
toluene
benzene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1,2,3 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
phenol
chloromethane
1,3 dichloropropane
hexachlorobutadiene
2-methylphenol
Car Washes SURF/VOC/SOC
toluene
benzene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
EDB
1,2,4 trimethylbenzene
MTBE
sodium
Cemeteries SOC/IOC
arsenic
atrazine
2,4-D
methoxychlor
glyphosate
simazine
carbaryl
dicamba
picloram
diazinon
pentachlorophenol
phenol
nitrate
nitrite
Dry Cleaners VOC
PCE
TCE
1,2 dichloropropane
1,1,1 TCA
Funeral Homes VOC
chloroform
pentachlorophenol
phenol
Furniture Stripping and
Refinishing
VOC/IOC
methylene chloride
benzene
chlorobenzene
o-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,1 DCE
1,2 dichloropropane
1,1,1 TCA
TCE
toluene
xylene
phenol
1,1,2,2 tetrachloroethane
tetrachloroethane
carbon tetrachloride
MEK
MIBK
methyl bromide
acetone
dimethyl phthalate
pentachlorophenol
antimony
barium
cadmium
mercury
lead
zinc
chromium
ethylbenzene
Gas/Service Stations VOC/SOC/IOC
toluene
benzene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1, 2,3 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
fluorotrichloromethane
2-methylphenol
Golf Courses SOC/IOC
atrazine
2,4-D
methoxychlor
glyphosate
simazine
carbaryl
dicamba
picloram
diazinon
nitrate
nitrite
arsenic
cadmium
mercury
cyanide
Junk Yards and Salvage
Yards
VOC/SOC/IOC
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1,2,3 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
Laundromats MIC/SURF/VOC
xylene
carbon tetrachloride
benzene
TCE
1,1,1 TCA
boron
Medical Facilities MIC/RAD/IOC/VOC
legionella
arsenic
benzene
bromoform
chloroform
chromium
1,1 DCA
mercury
methylene chloride
phenanthrene
phenol
selenium
silver
toluene
TCE
zinc
pentachlorophenol
1,1 dichlorobenzene
p-dichlorobenzene
styrene
thallium
acetone
1,2 DCE
dichlorodifluoromethane
trichlorofluoromethane
epichlorohydrin
1,1,1,2
tetrachloromethane
1,3 dichloropropane
radium
iodine
manganese
2,4,6 trichlorophenol
2,4 dintrophenol
1,2 diphenylhydrazine
2 -methylphenol
MTBE
nitrobenzene
Nursing Homes MIC legionella
Paint Shops VOC/IOC/SOC
acetone
methylene chloride
benzene
chlorobenzene
o-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,1 DCE
1,2 dichloropropane
1,1,1 TCA
TCE
toluene
xylene
phenol
1,1,2,2 tetrachloroethane
TCE
carbon tetrachloride
MEK
MIBK
methyl bromide
dimethyl phthalate
pentachlorophenol
antimony
barium
cadmium
mercury
lead
zinc
chromium
PCE
ethylbenzene
trichloromethane
1,2,4 trimethylbenzene
cyanide
di(2-ethylhexyl) phthalate
hexylphthalate
dichlorofluoromethane
boron
Photo Processors VOC/IOC/SOC
cyanide
2,4 dinitrophenol
cadmium
silver
diethyl phthalate
phenol
selenium
Printer and Blueprint Shops VOC/IOC
barium
cadmium
chromium
cobalt
lead
selenium
MEK
MIBK
methylene chloride
silver
TCE
PCE
cumene
ethylbenzene
antimony
cyanide
xylene
1,1,1 TCA
1,1,2 TCA
benzene
toluene
acetone
2,4 dinitrophenol
naphthalene
ethylbenzene
nitrate
zinc
Railroad Tracks and Yards VOC/SOC/IOC
2,4-D
glyphosate
picloram
diquat
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1,2,3 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
bromobenzene
Repair Shops (Small
Engine, Appliances, etc.)
VOC
benzene
carbon tetrachloride
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
1,1,1 TCA
TCE
toluene
1,1 DCA
1,2 DCA
fluorotrichloromethane
dichlorodifluoromethane
1,1,2,2 tetrachloroethane
acetone
naphthalene
mercury
thallium
antimony
methylene chloride
1,2,4 trichlorobenzene
methyl bromide
nitrobenzene
Research Laboratories VOC/SOC/
MIC/RAD/IOC
silver
pyrene
phenanthrene
methylene chloride
acetone
thallium
selenium
arsenic
benzene
1,1 DCA
styrene
toluene
TCE
pentachlorophenol
dichlorodifluoromethane
uranium
manganese
Rust Proofers VOC/IOC
zinc
phenol
1,1,1,2 tetrachloroethane
Sand and Gravel
Mining/Washing
VOC
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
INDUSTRIAL Contaminants of Concern
Asphalt,Coal Tar, and
Concrete Plants
VOC/SOC
TCE
1,1,1 TCA
1,2 DCE
methylene chloride
chloroform
MEK
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
sulfate
Chemical Manufacture or
Storage
VOC/SOC/IOC
benzene
toluene
xylene
TCE
methylene chloride
hexachlorobenzene
dioxin
o-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,2 dichloropropane
ethylbenzene
PCE
vinyl chloride
tribromomethane
1,1,2,2 tetrachloroethane
mercury
acetone
phenol
silver
1,1,2 TCA
2,4 dichlorophenol
2,4 dinitrotoluene
methyl bromide
chromium
sodium
MEK
MIBK
naphthalene
nickel
nitrate
chlorobenzene
MTBE
antimony
barium
chromium
lead
tert butylbenzene
sec butylbenzene
hexachlorobutadiene
1,2,3 trichlorobenzene
p-dichlorobenzene
bromobenzene
1,3 dichloropropene
chloromethane
chlorobenzene
acrylamide
epichlorohydrin
hexachloropentadiene
diethyl phthalate
di(2-ethylhexyl)phthalate
bromodichloromethane
dibromomethane
1,1,1 TCA
toluene
MTBE
MEK
MIBK
nitrate
antimony
barium
nickel
alumimum
chromium
nickel
zinc
cyanide
styrene
cumene
bis 2 chloroethylether
p-chloroaniline
2,4 dimethylphenol
methyl mercury
2- methylnaphthalene
2,4,5 trichlorophenol
2,4,6 trichlorophenol
2,6 nitrotoluene
nitrobenzene
sodium
Electronics Manufacture VOC/IOC/SOC
carbon tetrachloride
TCE
PCE
arsenic
mercury
antimony
beryllium
thallium
acetone
MEK
toluene
xylene
methylene chloride
styrene
lead
barium
arsenic
silver
selenium
zinc
nickel
cyanide
chromium
cadmium
barium
nitrate
di(2-ethylhexyl)phthalate
dichlorofluoromethane
2-methylphenol
Electroplaters VOC/IOC
carbon tetrachloride
1,2 dichloropropane
chlorobenzene
PCE
1,1,1 TCA
TCE
o-dichlorobenzene
1,1 DCA
1,2 DCA
1,1,2,2 tetrachloroethane
cadmium
chromium
cyanide
nickel
phenol
Food Processors MIC/IOC
nitrate
nickel
barium
xylene
zinc
phenol
bromomethane
Foundries or Metal
Fabricators
VOC/IOC/SOC
carbon tetrachloride
1,2 DCA
1,1 DCA
1,2 dichloropropane
chlorobenzene
PCE
1,1,1 TCA
1,1,2,2 TCA
naphthalene
arsenic
cadmium
chromium
antimony
cyanide
selenium
nickel
methylene chloride
antimony
zinc
barium
silver
lead
vanadium
acetone
phenol
TCE
toluene
MEK
MIBK
xylene
ethylbenzene
nitrate
dichlorofluoromethane
hexachlorobenzene
di(2-ethylhexyl)phthalate
styrene
dimethyl phthalate
sodium
manganese
boron
aluminum
o-dichlorobenzene
trichlorofluoromethane
1,1,2 TCA
pyridine
Fuel Oil Distributors VOC/SOC/IOC
pyrene
fluorene
fluoranthene
benzoanthracene
chrysene
benzo(a)pyrene
phenanthrene
naphthalene
2-methylnaphthalene
benzene
xylene
dibenzo(a,h)anthracene
ethylbenzene
xylene
toluene
arsenic
cadmium
chromium
lead
nickel
zinc
vanadium
MTBE
MIBK
cumene
methylene chloride
MEK
TCE
111 TCA
PCE
1,3,5 trimethylbenzene
Gasification Plants
(Oil or Coal)
VOC/SOC/IOC
benzo(a)pyrene
naphthalene
barium
cadmium
chromium
nitrate
selenium
antimony
cyanide
nickel
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(a,k)flouranthene
benzo(g,h,i)perylene
chrysene
benzo(a,h)anthracene
2,4 dimethylphenol
fluorothene
fluorene
2-methylnaphthalene
phenanthrene
phenol
pyrene
sulfate
2-methylphenol
vanadium
zinc
Hazardous Waste Storage,
Treatment and Recycling
VOC/SOC/IOC
PCBs
pentachlorophenol
hexachlorobenzene
benzene
carbon tetrachloride
o-dichlorobenzene
p-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,1 DCE
1, 2 dichloropropane
ethylbenzene
chlorobenzene
styrene
PCE
1,1,1 TCA
TCE
toluene
vinyl chloride
xylene
tribromomethane
1,1,2,2 tetrachloroethane
1,2,3 trichloropropane
naphthalene
fluorotrichloromethane
dichlorofluoromethane
asbestos
arsenic
barium
cadmium
chromium
mercury
selenium
antimony
beryllium
cyanide
nickel
thallium
lead
acetone
di(2-ethylhexyl)phthalate
2-chlorophenol
fluorene
hexachloroethane
MEK
MIBK
methylene chloride
phenanthrene
phenol
pyrene
silver
1,2,4 trichlorobenzene
1,1,2 trichloroethane
2,4,6 trichlorophenol
2,4 dichlorophenol
2,4 dinitrophenol
methyl bromide
zinc
p-chlorotoluene
bromobenzene
1,3,5 trimethylbenzene
1,2,3 trichlorobenzene
n-butyl benzene
hexachlorobutadiene
cumene
Industrial Lagoons and Pits VOC/SOC/IOC
PCBs
pentachlorophenol
hexachlorobenzene
benzene
carbon tetrachloride
o-dichlorobenzene
p-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,1 DCE
1,2 dichloropropane
ethylbenzene
chlorobenzene
styrene
PCE
111TCA
TCE
toluene
vinyl chloride
xylene
tribromomethane
1,1,2,2 tetrachloroethane
1,2,3 trichloropropane
naphthalene
fluorotrichloromethane
dichlorofluoromethane
asbestos
asenic
barium
cadmium
chromium
mercury
selenium
antimony
beryllium
cyanide
nickel
thallium
lead
acetone
di(2-ethylhexyl)phthalate
2-chlorophenol
fluorene
hexachloroethane
MEK
MIBK
methylene chloride
phenanthrene
phenol
pyrene
silver
1,2,4 trichlorobenzene
1,1,2 trichloroethane
2,4,6 trichlorophenol
2,4 dichlorophenol
2,4 dinitrophenol
methyl bromide
zinc
Industrial Parks VOC/SOC/IOC
PCBs
pentachlorophenol
hexachlorobenzene
benzene
carbon tetrachloride
o-dichlorobenzene
p-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,1 DCE
1,2 dichloropropane
ethylbenzene
chlorobenzene
styrene
PCE
1,1,1 TCA
TCE
toluene
vinyl chloride
xylene
tribromomethane
1,1,2,2 tetrachloroethane
1,2,3 trichloropropane
naphthalene
fluorotrichloromethane
dichlorofluoromethane
asbestos
asenic
barium
cadmium
chromium
mercury
selenium
antimony
beryllium
cyanide
nickel
thallium
lead
acetone
di(2-ethylhexyl)phthalate
2-chlorophenol
fluorene
hexachloroethane
MEK
MIBK
methylene chloride
phenanthrene
phenol
pyrene
silver
1,2,4 trichlorobenzene
1,1,2 trichloroethane
2,4,6 trichlorophenol
2,4 dichlorophenol
2,4 dinitrophenol
methyl bromide
zinc
dimethyl phthalate
diethyl phthalate
nitrate
aluminum
acrylamide
1,3 dichloropropane
epichlorohydrin
1,2,4 trimethylbenzene
1,3,5 trimethylbenzene
1,2 diphenylhydrazine
aluminum
Jewelry or Metalplating VOC/IOC
carbon tetrachloride
1,2 dichloropropane
chlorobenzene
PCE
1,1,1-TCA
TCE
o-dichlorobenzene
1,1 DCA
1,2 DCA
1,1,2,2 tetrachloroethane
cadmium
chromium
cyanide
nickel
phenol
barium
aluminum
lead
silver
zinc
nitrate
toluene
xylene
methylene chloride
MEK
MIBK
acetone
ethylbenzene
o-dichlorobenzene
trichlorofluoromethane
1,1,2 TCA
pyridine
Machine/ Metalworking
Shops
VOC/IOC
carbon tetrachloride
1,2 DCA
1,1 DCA
1,2 dichloropropane
chlorobenzene
PCE
1,1,1 TCA
1,1,2,2 tetrachloroethane
naphthalene
arsenic
cadmium
chromium
antimony
cyanide
selenium
nickel
methylene chloride
phenol
silver
barium
lead
zinc
nitrate
styrene
ethylbenzene
MEK
MIBK
toluene
acetone
PCE
TCE
xylene
nitrobenzene
o-dichlorobenzene
trichlorofluoromethane
1,1,2 TCA
pyridine
Metal and Drum
Cleaning/Reconditioning
VOC/SOC/IOC
PCBs
pentachlorophenol
hexachlorobenzene
benzene
carbon tetrachloride
o-dichlorobenzene
p-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,1 DCE
1,2 dichloropropane
ethylbenzene
chlorobenzene
styrene
PCE
1,1,1 TCA
TCE
toluene
vinyl chloride
xylene
tribromomethane
1,1,2,2 tetrachloroethane
1,2,3 trichloropropane
naphthalene
fluorotrichloromethane
dichlorofluoromethane
asbestos
asenic
barium
cadmium
chromium
mercury
selenium
antimony
beryllium
cyanide
nickel
thallium
lead
acetone
di(2-ethylhexyl)phthalate
2-chlorophenol
fluorene
hexachloroethane
MEK
MIBK
methylene chloride
phenanthrene
phenol
pyrene
silver
1,2,4 trichlorobenzene
1,1,2 trichloroethane
2,4,6 trichlorophenol
2,4 dichlorophenol
2,4 dinitrophenol
methyl bromide
zinc
Nuclear Power Plants MIC/RAD/IOC
radium 226
radium 228
radium 222
Gross Beta
Gross Alpha
cadmium
uranium
beryllium
strontium
boron
vanadium
Paper Manufacture VOC/IOC
aluminum
antimony
zinc
MEK
xylene
toluene
phenol
Pharmaceutical
Manufacture
VOC/SOC
dichlorodifluoromethane
methylene chloride
trichlorofluoromethane
1,3 dichloropropane
nitrobenzene
manganese
Plastic Manufacture VOC/SOC/IOC
aluminum
antimony
barium
methylene chloride
diethyl phthalate
epichlorohydrin
ethylbenzene
lead
MEK
MIBK
nitrate
phenol
styrene
toluene
1,2,4 trimethylbenzene
xylene
zinc
PCE
TCE
difluorochloromethane
cyanide
nickel
chromium
cadmium
silver
acetone
RCRA TSDF Facilities VOC/SOC/IOC
PCBs
pentachlorophenol
hexachlorobenzene
benzene
carbon tetrachloride
o-dichlorobenzene
p-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,2 DCE
1,1 DCE
1,2 dichloropropane
ethylbenzene
chlorobenzene
styrene
PCE
1,1,1 TCA
TCE
toluene
vinyl chloride
xylene
tribromomethane
1,1,2,2 tetrachloroethane
1,2,3 trichloropropane
naphthalene
fluorotrichloromethane
dichlorofluoromethane
asbestos
asenic
barium
cadmium
chromium
mercury
selenium
antimony
beryllium
cyanide
nickel
thallium
lead
acetone
di(2-ethylhexyl)phthalate
2-chlorophenol
fluorene
hexachloroethane
MEK
MIBK
methylene chloride
phenanthrene
phenol
pyrene
silver
1,2, 4 trichlorobenzene
1, 1, 2 trichloroethane
2,4,6 trichlorophenol
2,4 dichlorophenol
2 ,4 dinitrophenol
methyl bromide
zinc
Tanneries VOC/IOC/SOC
benzene
o-dichlorobenzene
p-dichlorbenzene
toluene
naphthalene
arsenic
chromium
anthracene
di(2-ethylhexyl)phthalate
dimethyl phthalate
phenanthrene
2,4,6 trichlorophenol
2,4 dichlorophenol
zinc
pentachlorophenol
cyanide
cadmium
Textile Manufacture VOC/IOC
antimony
chromium
barium
lead
zinc
phenol
xylene
MIBK
TCE
MEK
toluene
Wood Preserving Facilities SOC/IOC
2,4 dinitrophenol
pentachlorophenol
anthracene
aldrin
naphthalene
cadmium
arsenic
chromium
RESIDENTIAL Contaminants of Concern
Fuel Oil Storage VOC/SOC/IOC
pyrene
fluorene
fluoranthene
benzoanthracene
chrysene
benzo(a)pyrene
phenanthrene
naphthalene
2-methylnaphthalene
benzene
xylene
dibenzo(a,h)anthracene
ethylbenzene
xylene
toluene
arsenic
cadmium
chromium
lead
nickel
zinc
vanadium
MTBE
MIBK
Lawn Care SOC/IOC
atrazine
2,4 -D
methoxychlor
glyphosphate
dicamba
carbaryl
arsenic
mercury
diazinon
Septic Systems/Cesspools MIC/VOC/IOC
nitrate
nitrite
benzene
toluene
xylene
ethylbenzene
MTBE
TCE
acetone
fluoride
methylene chloride
sulfate
1,1,1 TCA
PCE
carbon tetrachloride
phenol
MEK
MIBK
styrene
p-dichlorobenzene
naphthalene
cyanide
silver
MISCELLANEOUS Contaminants of Concern
Aboveground Storage
Tanks
VOC/SOC/IOC
pyrene
fluorene
fluoranthene
benzoanthracene
chrysene
benzo(a)pyrene
phenanthrene
naphthalene
2-methylnaphthalene
benzene
xylene
dibenzo(a,h)anthracene
ethylbenzene
xylene
toluene
arsenic
cadmium
chromium
lead
nickel
zinc
vanadium
MTBE
MIBK
Aquatic Wildlife MIC
Clandestine Dumping VOC/SOC/IOC
PCBs
pentachlorophenol
hexachlorobenzene
benzene
carbon tetrachloride
o-dichlorobenzene
p-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,1 DCE
1,2 dichloropropane
ethylbenzene
chlorobenzene
styrene
PCE
1,1,1 TCA
TCE
toluene
vinyl chloride
xylene
tribromomethane
1,1,2,2 tetrachloroethane
1,2,3 trichloropropane
naphthalene
fluorotrichloromethane
dichlorofluoromethane
asbestos
asenic
barium
cadmium
chromium
mercury
selenium
antimony
beryllium
cyanide
nickel
thallium
lead
acetone
di(2-ethylhexyl)phthalate
2-chlorophenol
fluorene
hexachloroethane
MEK
MIBK
methylene chloride
phenanthrene
phenol
pyrene
silver
1,2,4 trichlorobenzene
1,1,2 trichloroethane
2,4,6 trichlorophenol
2,4 dichlorophenol
2,4 dinitrophenol
methyl bromide
zinc
Combined Sewer Outfalls MIC/IOC/SOC
VOC
nitrate
nitrite
TCE
benzene
toluene
ethylbenzene
xylene
MTBE
benzo(a)pyrene
naphthalene
dichlorodifluoromethane
arsenic
barium
cadmium
chromium
cyanide
selenium
silver
mercury
lead
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,k)fluoranthene
benzo(g,h,i)perylene
chrysene
fluoranthene
fluorene
2-methylnaphthalene
pryene
Composting Facilities MIC/IOC
nitrate
nitrite
Dredge Disposal Facilities IOC
arsenic
cadmium
chromium
copper
lead
mercury
nickel
PCBs
vanadium
zinc
Fire Training Facilities VOC/IOC/SOC
toluene
ethylbenzene
xylene
benzene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MBTE
EDB
1,2,4-trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-diclorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
PCE
1,1 DCA
1,2 DCA
methylene chloride
1,2, 3 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
chromodibromomethane
fluorotrichloromethane
bromodichloromethane
dichlorodifluoromethane
Fishing/Boating VOC/MIC
benzene
toluene
xylene
ethylbenzene
beryllium
hexachloroethane
MEK
MIBK
methylene chloride
Landfills and Dumps VOC/SOC/
IOC
styrene
nitrate
sulfate
arsenic
barium
cadmium
chromium
cyanide
lead
mercury
selenium
silver
TCE
hexachloroethane
carbon tetrachloride
1,1 DCE
1,2 DCE
chlorobenzene
1,4 dichlorobenzene
MEK
MIBK
hexachlorobenzene
benzene
dichlorodifluoromethane
PCBs
methylene chloride
Land Application of Sewage
Sludge
IOC/SOC
cadmium
chromium
barium
arsenic
lead
mercury
silver
selenium
endrin
lindane
methoxychlor
toxaphene
PCBs
Large Quantity Hazardous
Waste Generator
VOC/SOC/IOC
PCBs
pentachlorophenol
hexachlorobenzene
benzene
carbon tetrachloride
o-dichlorobenzene
p-dichlorobenzene
1,2 DCA
1,1 DCA
1,2 DCE
1,1 DCE
1,2 dichloropropane
ethylbenzene
chlorobenzene
styrene
PCE
1,1,1 TCA
TCE
toluene
vinyl chloride
xylene
tribromomethane
1,1,2,2 tetrachloroethane
1,2,3 trichloropropane
naphthalene
fluorotrichloromethane
dichlorofluoromethane
asbestos
asenic
barium
cadmium
chromium
mercury
selenium
antimony
beryllium
cyanide
nickel
thallium
lead
acetone
di(2-ethylhexyl)phthalate
2-chlorophenol
fluorene
hexachloroethane
MEK
MIBK
methylene chloride
phenanthrene
phenol
pyrene
silver
1,2,4 trichlorobenzene
1,1,2 trichloroethane
2,4,6 trichlorophenol
2,4 dichlorophenol
2,4 dinitrophenol
methyl bromide
zinc
dimethyl phthalate
diethyl phthalate
nitrate
aluminum
acrylamide
1,3 dichloropropane
epichlorohydrin
1,2,4 trimethylbenzene
1,3,5 trimethylbenzene
1,2 diphenylhydrazine
aluminum
Military Facilities VOC/SOC/
IOC
PCBs
benzene
ethylbenzene
TCE
PCE
1,1,1 TCA
toluene
xylene
EDB
1,2,4 trimethylbenzene
cumene
naphthalene
1,3,5 trimethylbenzene
n-propylbenzene
beryllium
hexachloroethane
MEK
MTBE
2-methylnaphthalene
MIBK
methylene chloride
phenanthrene
2,4 dinitrophenol
2,4 dinitrotoluene
RDX
4 nitrophenol
cyanide
selenium
antimony
acetone
zinc
lead
cadmium
chromium
barium
arsenic
alumimum
vanadium
di(2-ethylhexyl)phthalate
endosulfan
2,6 dinitrotoluene
NPDES Locations MIC/IOC/VOC
nitrate
nitrite
TCE
benzene
toluene
ethylbenzene
xylene
MTBE
benzo(a)pyrene
naphthalene
dichlorodifluoromethane
arsenic
barium
silver
cadmium
chromium
cyanide
mercury
lead
selenium
sulfate
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,k)fluoranthene
benzo(g,h,i)perylene
chrysene
fluoranthene
fluorene
2-methylnaphthalene
pyrene
Pipelines
(Oil and Sewer)
VOC/SOC/IOC
pyrene
fluorene
fluoranthene
benzo(a)anthracene
chrysene
benzo(a)pyrene
phenanthrene
naphthalene
2-methylnaphthalene
benzene
xylene
dibenzo(a,h)anthracene
ethylbenzene
xylene
toluene
arsenic
cadmium
chromium
lead
nickel
zinc
vanadium
MTBE
MIBK
cumene
methylene chloride
MEK
TCE
1,1,1 TCA
PCE
1,2,4 trimethylbenzene
Prisons MIC/VOC
benzene
carbon tetrachloride
1,1 DCE
ethyl benzene
1,1,1 TCA
toluene
xylene
TCE
methylene chloride
1,1 DCA
1,2 DCA
naphthalene
acetone
MEK
MIBK
Road and Maintenance
Depots
VOC/IOC/SOC
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
monochlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1,2,3 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
Schools, Colleges and
Universities
VOC/IOC/SOC
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1,2 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
phenol
chloroethane
bromobenzene
hexachlorobutadiene
silver
thallium
selenium
manganese
uranium
styrene
phenanthrene
indeno(1,2,3-cd)pyrene
pentachlorophenol
cyanide
Small Quantity Hazardous
Waste Generator
VOC/IOC/SOC
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1,2,3 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
phenol
chloroethane
bromobenzene
hexachlorobutadiene
carbon tetrachloride
fluorotrichloromethane
1,1,2,2, tetrachloroethane
thallium
antimony
1,2,4 trichlorobenzene
methyl bromide
nitrobenzene
Snow Dumps IOC/VOC
sodium
benzene
toluene
xylene
ethylbenzene
Stormwater Drains/
Retention Basins
MIC/IOC/VOC/SOC
nitrate
nitrite
TCE
benzene
toluene
ethylbenzene
xylene
MTBE
benzo(a)pyrene
naphthalene
dichlorodifluoromethane
arsenic
barium
cadmium
chromium
mercury
lead
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k)fluoranthene
benzo(g,h,i)perylene
chrysene
fluoranthene
fluorene
2-methylnaphthalene
pryene
Tire Dumps VOC/SOC
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acenaphthalate
acenaphthene
anthracene
benzo(a)anthracene
benzo(a)pyrene
benzo(b) fluoranthene
chrysene
dibenzo(a,h) anthracene
fluoranthene
fluorene
indeno(1,2,3-cd)pyrene
pyrene
Transmission Line Right-of-
Ways
SOC
glyphosate
picloram
Transportation Corridors VOC/IOC/SOC
glyphosate
picloram
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
1,2,4 trimethyl benzene
benzo(a)pyrene
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
Underground Storage
Tanks
VOC/SOC/IOC
pyrene
fluorene
fluoranthene
benzo(a)anthracene
chrysene
benzo(a)pyrene
phenanthrene
naphthalene
2-methylnaphthalene
benzene
xylene
dibenzo(a,h)anthracene
ethylbenzene
xylene
toluene
arsenic
cadmium
chromium
lead
nickel
zinc
vanadium
MTBE
MIBK
Utility Substation
Transformers
VOC
PCBs
1,2,3 trichlorobenzene
1,1 biphenyl
1,2,4 trichlorobenzene
Very Small Quantity
Generators
VOC/IOC/SOC
benzene
toluene
ethylbenzene
xylene
naphthalene
2-methylnaphthalene
phenanthrene
acetone
MEK
MIBK
MTBE
EDB
1,2,4 trimethylbenzene
arsenic
barium
cadmium
chromium
lead
mercury
zinc
PCBs
o-dichlorobenzene
1,2 dichloropropane
chlorobenzene
tetrachloroethylene
1,1,1 TCA
TCE
1,1 DCA
1,2 DCA
methylene chloride
1,2,3 trichlorobenzene
benzo(a)pyrene
dichlorodifluoromethane
acenaphthene
acenaphthylene
anthracene
benzo(a)anthracene
benzo(b,j,k) fluoranthene
benzo(g,h,i) perylene
chrysene
fluoranthene
fluorene
pyrene
phenol
chloroethane
bromobenzene
hexachlorobutadiene
carbon tetrachloride
fluorotrichloromethane
1,1,2,2, tetrachloroethane
thallium
antimony
1,2,4 trichlorobenzene
methyl bromide
nitrobenzene
Waste Incinerators SOC
chrysene
hexachloroethane
ideno(1,2,3-c,d) pyrene
cyanide
2,4 dinitrophenol
n-propyl benzene
Waste Transfer Stations VOC/IOC
styrene
nitrate
sulfate
arsenic
barium
cadmium
chromium
cyanide
lead
mercury
silver
TCE
carbon tetrachloride
1,1 DCE
1,2 DCE
chlorobenzene
MEK
MIBK
methylene chloride
benzene
Wastewater Treatment
Plants
VOC/IOC/MIC
methylene chloride
nitrite
nitrate
arsenic
barium
cadmium
chromium
cyanide
lead
copper
mercury
selenium
silver
zinc
sulfate
trichloromethane
1,2,3 trichlorobenzene
n- propyl benzene
Water Treatment Sludge
Lagoons
IOC
manganese
aluminum
arsenic
radon
Model Zone A Bylaw Revisions Proposed for Cohasset
Article ( ). To see if the Town will vote to amend Section 14, “Water Resource District” of the Zoning
Bylaws by inserting a new Section 14.2A:
14.2A Definitions
For the purposes of this Section of the Bylaw, the following terms and words are given the meanings
stated below.
Bank. The portion of land surface which normally abuts and confines a water body and which lies between a
water body and a bordering vegetated wetland and adjacent floodplain, or in the absence of these features, it lies
between a water body and an upland; the upper boundary of a bank is the first observable break in the slope or
the mean annual flood level; whichever is lower, the lower boundary of a bank is the mean annual low flow
level.
Department. The Massachusetts Department of Environmental Protection
Zone A. Zone A means:
(a) the land area between the surface of Lily Pond, the Aaron River Reservoir, and the tributaries or associated
surface water bodies to Lily Pond and the Aaron River Reservoir, which includes Bound Brook/Herring
Brook, Aaron River, Peppermint Brook, and Brass Kettle Brook, and the upper boundary of the bank; and
(b) the land area within a 400 foot lateral distance from the upper boundary of the banks of Lily Pond and the
Aaron River Reservoir, and
(c) the land area within a 200 foot lateral distance from the upper boundary of the banks of a tributary or
associated surface water body to Lily Pond and the Aaron River Reservoir, which includes Bound
Brook/Herring Brook, Aaron River, Peppermint Brook, and Brass Kettle Brook.
(d) The area of land described in subparagraph (a), (b) and (c) immediately above, is generally depicted on a
map entitled “Zone A Delineation” prepared by the Norfolk Ram Group, LLC, dated March 2002 and which
is on file with the Town Clerk. The Zone A areas shown on this map are provided to generally depict the
above noted limits of the Zone A areas around the protected waters, in relation to known parcels of land of
record at the Cohasset Assessors office. The specific Zone A limits as defined in (a), (b) and (c)
immediately above (e.g. 200 foot or 400 foot lateral distances) shall control in all maters of interpretation of
this map.
and by inserting a new Section 14.3.1(A):
14.3.1A Prohibitions within Zone A of Public Drinking Water Supply
In addition to the uses prohibited in the Water Resource District pursuant to Section 14.3.1, the
following uses are prohibited within Zone A:
(a) All underground storage tanks,
(b) All above-ground storage of liquid hazardous material as defined in M.G.L. c.21E, or liquid propane or
liquid petroleum products, except as follows:
1. Storage is incidental to:
a. normal household use, outdoor maintenance, or the heating of a structure;
b. use of emergency generators;
c. a response action conducted or performed in accordance with M.G.L. c.21E and 310 CMR 40.000 which is
exempt from a ground water discharge permit pursuant to 314 CMR 5.05(14); and
2. Storage is within a building, either in container(s) or above-ground tank(s), or outdoors in covered
container(s) or above-ground tank(s) in an area that has a containment system designed and
operated to hold either 10% of the total possible storage capacity of all containers, or 110% of the
largest container's storage capacity, whichever is greater. However, these storage requirements do
not apply to the replacement of existing tanks or systems for the keeping, dispensing or storing of
gasoline provided the replacement is performed in accordance with applicable state and local
requirements;
(c) Treatment or disposal works subject to 314 CMR 3.00 or 5.00, except the following:
1. the replacement or repair of an existing treatment or disposal works that will not result in a design
capacity greater than the design capacity of the existing treatment or disposal works;
2. treatment or disposal works for sanitary sewage if necessary to treat existing sanitary sewage discharges in
non-compliance with Title 5, 310 CMR 15.00, provided the facility owner demonstrates to the Department's
satisfaction that there are no feasible siting locations outside of the Zone A. Any such facility shall be
permitted in accordance with 314 CMR 5.00 and shall be required to disinfect the effluent. The Department
may also require the facility to provide a higher level of treatment prior to discharge;
3. treatment works approved by the Department designed for the treatment of contaminated ground or surface
waters and operated in compliance with 314 CMR 5.05(3) or 5.05 (13).
4. discharge by public water system of waters incidental to water treatment processes.
(d) facilities that, through their acts or processes, generate, treat, store or dispose of hazardous waste that are
subject to M.G.L. c. 21C and 310 CMR 30.000, except for the following:
1. very small quantity generators, as defined by 310 CMR 30.000;
2. treatment works approved by the Department designed in accordance with 314 CMR 5.00 for the
treatment of contaminated ground or surface waters;
(e) sand and gravel excavation operations;
(f) uncovered or uncontained storage of fertilizers;
(g) uncovered or uncontained storage of road or parking lot de-icing and sanding materials;
(h) storage or disposal of snow or ice, removed from highways and streets outside the Zone A, that contains
deicing chemicals;
(i) uncovered or uncontained storage of manure;
(j) junk and salvage operations;
(k) motor vehicle repair operations;
(l) cemeteries (human and animal) and mausoleums;
(m)solid waste combustion facilities or handling facilities as defined at 310 CMR 16.00;
(n) land uses that result in the rendering impervious of more than 15%, or more than 20% with artificial
recharge, or 2500 square feet of any lot, whichever is greater; and
(o) commercial outdoor washing of vehicles, commercial car washes.
(p) dry-cleaning establishments;
(q) metal plating, finishing, or polishing;
(r) chemical of bacteriological laboratories;
(s) commercial photographic processing;
(t) commercial printing other than xerographic reproduction;
(u) self-service laundries unless sewered;
(v) hotels or motels unless sewered;
(w)cabinet/furniture making establishments;
(x) painting, wood preserving and furniture stripping establishments; and
(y) electronic circuit assembly facilities.
; and by amending Section 14.3.2 by striking the first sentence and inserting in place thereof the following:
The following uses and activities are permitted in the Water Resource District, exclusive of the Zone A area,
only upon the issuance of a Special Permit by the Zoning Board of Appeals (“the Board”) under such conditions
as the Board may require.
; or to take any other action relative thereto.
MEMO
To: Mr. John McNabb, Chairman
Cohasset Water Commission
From: David Tanguay, Norfolk Ram Group
Date: April 2, 2002
Re: Stormwater Drainage in the Lily Pond Tributary
Norfolk Job # 158.09
Cc: Mark Bartlett, P.E., Norfolk Ram Group
*******************************************************************************************
Between the dates of October 18, 2001 and October 29, 2001 Norfolk Ram Group had been conducting fieldwork to assess the extent
of the stormwater drainage system within the Lily Pond tributary. Fieldwork included the locating, measuring distances and field
mapping of all Stormwater catch basins, headwalls and Stormwater swales within the hydrologic topographical divide of Lily Pond.
To date, the following street and numbers of drainage systems have been mapped:
Street Name # Systems*
State Highway 3A, King St. to Beechwood St. 9
King St. 1
Pond St. 3
Bailey Rd. 0
Hugh Strain Rd. 0
Lily Pond Lane 1
Whitney Woods Lane 1
Beechwood St. 6
Bound Brook Lane 1
Mill Lane 1
Wheelwright Farm 1
River View Dr. 2
Doane St. 2
Church St. 1
Bates Lane 1
Buttonwood Lane 0
Clayspring Rd. 1
Bayberry Lane 1
Tupelo Rd. 1
Arrowwood St. 1
Old Pasture Rd. 1
If you have any questions about this fieldwork please contact David Tanguay, (508) 822-5500 ext. 35.
* System meaning catch basins and drain lines within a definite beginning and ending (outfall of undetermined end).