HomeMy WebLinkAboutAppendix G O&M PlanLONG-TERM POLLUTION PREVENTION AND
STORMWATER MANAGEMENT SYSTEM
OPERATION AND MAINTENANCE PLAN
SOUTH YARMOUTH LNG PROJECT
SOUTH YARMOUTH, MASSACHUSETTS
DECEMBER 2025
Prepared for:
National Grid
Table of Contents Tighe&Bond
Section 1 Introduction and Purpose
Section 2 Responsible Parties
Section 3 Long Term Pollution Prevention Plan
3.1 Good Housekeeping........................................................................3-1
3.1.1 Local Standards...................................................................3-1
3.2 Potential Sources of Pollution...........................................................3-2
3.3 General Spill Prevention and Response..............................................3-2
3.3.1 Federal and State Spill Notification.........................................3-3
3.3.2 Local Notification..................................................................3-3
3.4 Storage, Handling, and Disposal of Materials and Wastes ....................3-4
3.4.1 Pesticides, Herbicides, Insecticides, Fertilizers, and Landscaping
Materials.............................................................................3-4
3.4.3 Hazardous or Toxic Waste.....................................................3-4
3.4.4 Domestic Waste...................................................................3-5
Section 4 Stormwater Management System
4.1 Inspections....................................................................................4-1
4.1.1 Vegetated Surfaces..............................................................4-1
4.1.2 Driveway and Walkway Sweeping...........................................4-1
4.1.3 Deep -Sump, Hooded Catch Basins..........................................4-1
4.1.4 Proprietary Water Treatment Devices.....................................4-2
4.1.6 Surface Infiltration Basin.......................................................4-2
4.1.7 Infiltration Trenches.............................................................4-2
4.1.13 Stone End Protection (Outfalls)..............................................4-3
Section 5 Operation and Maintenance Log Form
Section 6 Snow Management & De -Icing
Section 7 Estimated O&M Budget
Table of Contents Tighe&Bond
Appendices
Stormwater BMP Location Map
]:\C\C5200 CH-IV\South Yarmouth LNG - 001\Permitting\Stormwater\Appendix F - Stormwater 0&M\Long Term Pollution Prevention and
Stormwater Management OM Plan.doc
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Section 1
Introduction and Purpose
The following Long -Term Pollution Prevention and Stormwater Operations and
Maintenance (O&M) Plan has been prepared for the stormwater management system at
the proposed South Yarmouth LNG project in South Yarmouth, Massachusetts. The
purpose of the plan is to provide guidance and procedures for proper pollution
prevention and stormwater management system maintenance following construction
completion.
The proposed project has been designed in compliance with the Massachusetts
Department of Environmental Protection (MassDEP) Stormwater Handbook and the Town
of Yarmouth Stormwater Regulations to maintain or improve stormwater runoff quality
and quantity. The stormwater management system components shall be maintained as
recommended in the Massachusetts Stormwater Handbook.
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Section 2
Responsible Parties
National Grid is responsible for maintaining and servicing the proposed driveway, paved
and unpaved parking and storage areas, landscaping, utility infrastructure and the
stormwater management facilities post construction. The property is owned by Boston
Gas Company. During construction, the contractor will be responsible for stormwater
management system maintenance.
Applicant/Property Owner:
Matthew T. Wozniak
Boston Gas Company DBA National Grid
170 Data Drive
Waltham, MA 02451
Applicant Signature, date: j (,{J� 12/12/25
Maintenance Contact:
Jaylon Todman
Boston Gas Company DBA National Grid
127 Whites Path
South Yarmouth, MA 02664
Maintenance Contact j�cr
Signature, date: 12/12/25
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Section 3
Long Term Pollution Prevention Plan
3.1 Good Housekeeping
The goal of the good housekeeping policy is to keep the site in a clean and orderly
condition. A disorderly site can lead to improper materials management and can reduce
the efficiency of any response to potential pollution problems.
The following good housekeeping measures will be followed at the site to aid in pollution
prevention:
• Promptly clean and remove any spills or contamination from vehicles or other
services.
• Perform preventative maintenance on the structural components of the stormwater
system.
• Properly dispose of refuse.
3.1.1 Local Standards
South Yarmouth Good Housekeeping Standards, Projects shall meet the following
Performance Standards:
(2) Good housekeeping procedures shall be used to reduce sources of sediment,
phosphorus, nitrogen and other contaminants in stormwater runoff. These shall be
documented in the Operation and Maintenance Plan and must include:
(a) Wash vehicles at commercial car washes or on lawns or pervious areas using
biodegradable and phosphate free detergent;
(b) Removal of sediment, leaf litter and other organic debris from impervious surfaces a
minimum of twice a year in the spring (after snowmelt) and fall (after leaf fall);
(c) Removal of sediment/debris from catch basin structures a minimum of once a year;
(d) Restrictions on the application of fertilizers, including:
i. Fertilizer shall not be applied during or immediately prior to heavy rainfall, such
as but not limited to thunderstorms, hurricanes, or northeastern storms, or when
the soil is saturated due to intense or extended rainfall;
ii. Fertilizer shall not be applied between November 12 and the following March
31;
iii. Fertilizer shall not be applied, spilled or deposited on impervious surfaces or in
a manner that allows it to enter into storm drains;
iv. Fertilizer shall not be applied within 100 feet of any surface water or within
the Zone I of a public drinking water well;
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v. Fertilizer containing phosphorus shall not be applied unless a soil test taken
not more than three years before the proposed fertilizer application indicates that
additional phosphorus is needed for growth of that turf, or unless establishing
new turf or reestablishing or repairing turf after substantial damage or land
disturbance;
vi. A single application of fertilizer that contains nitrogen shall not exceed 1.0
pound of nitrogen per 1,000 square feet, shall consist of at least 20% slow -
release nitrogen (SRN) fertilizer (NOTE: This represents the minimum
percentage: use of higher SRN content is generally preferable, especially on
sandy root zones, during stress and pre -stress periods, and when there are fewer
annual applications of nitrogen made to a lawn) and the annual rate shall not
exceed 3.2 pounds of actual nitrogen per thousand square feet. Single
applications shall be done at intervals of no less than four weeks until the annual
maximum is reached;
vii. Grass clippings, leaves, or any other vegetative debris shall not be deposited
into or within 50 feet of water bodies, retention and detention areas, drainage
ditches or stormwater drains, or onto impervious surfaces, such as, but not limited
to, roadways and sidewalks, except during scheduled clean-upprograms; and (e)
Provide for routine inspection (at least annually) and maintenance of structural
BMPs to remove sediment and debris.
3.2 Potential Sources of Pollution
The following sources of pollution are anticipated as part of the long-term use of the
project.
Pollutant -Generating
Activity
Pollutants or Pollutant Constituents
(that could be discharged if exposed to stormwater)
Vehicular Access
Petroleum, concrete, vehicle fluids, paints, solvents
Solid waste storage
Construction debris, trash
Landscaping Activites
Fertilizers, pesticides, herbcides
Equipment use
Hydraulic oils, fluids, antifreeze, coolant
3.3 General Spill Prevention and Response
In the event of a spill, the following procedures shall be followed by the Maintenance
Contact or their authorized representative:
• Manufacturer's recommended methods for cleanup will be clearly posted and
facility personnel will be made aware of the procedures and the location of the
information and clean up supplies.
• Materials and equipment necessary for spill cleanup will be kept in the material
storage areas at the facility. Equipment and materials will include but not be
limited to brooms, dustpans, mops, rags, gloves, goggles, kitty litter, sand,
sawdust and plastic or metal trash containers specifically for this purpose.
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• All spills will be cleaned up immediately after discovery.
• The spill area will be kept well ventilated and personnel will wear appropriate
protective clothing to prevent injury from contact with hazardous substances.
• Spills of toxic or hazardous material will be reported to the appropriate state or
local government agency regardless of size.
• The Spill Prevention Plan will be adjusted to include measures to prevent this
type of spill from recurring and how to cleanup the spill if it recurs. A description
of the spill, its cause and the cleanup measures will be included.
• The Maintenance Contact is responsible for day to day operations will be the spill
prevention and cleanup coordinator.
3.3.1 Federal and State Spill Notification
In accordance with 310 CMR 40.0333, the Maintenance Contact shall notify the
Massachusetts Department of Environmental Protection (Southeast Region) - (508) 946-
2700 the Local Emergency Planning Committee (LEPC) (if applicable) and any other
authorities or agencies within two hours if an accident or other type of incident results in a
release to:
• land
0 10 Gallons for more Oils (PCB<500 ppm)
0 1 Gallon or more Oils (PCB >_500 ppm)
• waterways
o Any quantity of Oils
• Or, triggers the exposure to toxic chemical levels as listed in 301 CMR 40.1600,
Revised Massachusetts Contingency Plan (MPC)
The Maintenance Contact shall notify the National Response Center (NRC) at (800)
424-8802 where a leak, spill, or other release containing a hazardous substance or oil
in an amount equal to or in excess of a reportable quantity consistent with Part 2.3.3.4c
and established under either 40 CFR Part 110, 40 CFR Part 117, or 40 CFR Part 302,
occurs during a 24-hour period.
In either event, the Maintenance Contact will work with state and federal agencies to
ensure that all appropriate forms and reports are submitted in a timely manner.
• Note: Trigger volumes for other chemical spills vary. Contact the MassDEP or a
Licensed Site Professional (LSP) for specific guidance on reporting thresholds and
requirements for other chemicals.
3.3.2 Local Notification
The following local agencies will be called to provide emergency assistance at the facility
on the judgment of the Maintenance Contact:
Fire Department
911 or (508)-398-2212
Police Department
911 or (508) 775-0445
Hospital: Cape Cod Hospital
Department of Public Works:
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(508) 771-1800 1 (508) 398-2231 ext.1250
3.4 Storage, Handling, and Disposal of Materials and
Wastes
The following procedures shall be followed throughout the facility when storing, handling
and disposing of various materials.
3.4.1 Pesticides, Herbicides, Insecticides, Fertilizers, and Landscaping
Materials
• Store new and used materials in a neat, orderly manner in their appropriate
containers in a covered area. If storage in a covered area is not possible, the
materials shall be covered with polyethylene or polypropylene sheeting to protect
them from the elements.
• Storage area should include precautions to contain any potential spills.
• Immediately contain and clean up any spills with absorbent materials.
• Apply at a rate and in amounts consistent with manufacturer's specifications, or
document departures from the manufacturer's specifications.
• Apply at the appropriate time of year for the site, and preferably timed to
coincide as closely as possible to the period of maximum vegetation uptake and
growth
• Avoid applying before heavy rains that could cause excessive nutrients to be
discharged
• Never apply to frozen ground
• Never apply to stormwater conveyance channels with flowing water
• Follow all federal, state, tribal, and local requirements regarding fertilizer
application.
3.4.3 Hazardous or Toxic Waste
• Store new and used materials in a neat, orderly manner in their appropriate
containers in a covered area. If storage in a covered area is not possible, the
materials shall be covered with polyethylene or polypropylene sheeting to protect
them from the elements.
• Storage areas should include precautions to contain any potential spills.
• Immediately contain and clean up any spills with absorbent materials.
• Have equipment available in fuel storage areas and in vehicles to contain and
clean up any spills that occur.
• To prevent leaks, empty and clean hazerdous waste containers before disposing
of them.
• Never remove the original product label from the container because it contains
important safety information. Follow the manufacturer's recommended method of
disposal, which should be printed on the label.
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• Never mix excess products when disposing of them, unless specifically
recommended by the manufacturer.
3.4.4 Domestic Waste
• Site property manager shall designate a waste collection area on the site that
does not receive a substantial amount of runoff from upland areas and does not
drain directly to a water body.
• Ensure that containers have lids so they can be covered before periods of rain
and keep containers in a covered area whenever possible.
• Schedule waste collection to prevent the containers from overfilling.
• Clean up spills immediately. For hazardous materials, follow cleanup instructions
on the package. Use an absorbent material such as sawdust or kitty litter to
contain the spill.
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Section 4
Stormwater Management System
Under proposed conditions, stormwater runoff from the project area is all collected and
treated within the new stormwater system. No runoff from the redevelopment area will
enter the existing stormwater system on site. The stormwater runoff generally flows
south and is collected in catch basins, trench drains, or directly flows into a series of
sediment forebays. The runoff entering catch basins will flow through a series of drain
manholes and a Water Quality Treatment Unit. All run off from impervious vehicular
areas will reach the required 44% pretreatment before entering the basin for infiltration.
The infiltration basin has been sized to retain the volume of 1 inch per impervious.
See the attached Figures 1-3 in Appendix A for the location of the various described
components of the Stormwater Management System.
4.1 Inspections
Inspections will be performed in accordance with the Massachusetts Department of
Environmental Protection (MassDEP) Stormwater Handbook. Figure 3, provided in
Appendix A, identifies the location of each BMP to be inspected and maintained as
described in this Section. All inspections should be logged using the Inspection Forms
provided in Section 5.
The following stormwater management system features will be evaluated during each
inspection:
4.1.1 Vegetated Surfaces
Inspection Frequency: Bi-annually in Summer and Winter
Special Inspection Event(s): Spring Snow Melt
All vegetative surfaces will be observed to identify locations of settlement, erosion and
other impacts from the proposed access roads. Areas of settlement and erosion that
may result in a discharge of sediment into Waters of the Commonwealth shall be
repaired and restored to a vegetated condition.
4.1.2 Driveway and Walkway Sweeping
Inspection Frequency: Quarterly
Special Inspection Event(s): Spring Snow Melt
All pavement surfaces should be inspected annually for deterioration or spalling.
Additionally, the pavement surface should be regularly monitored to make sure it drains
properly after storms. Cleanings should be conducted on a quarterly basis to prevent
clogging. For best management practices, high -efficiency vacuum sweeping machines
should be used to clean and maintain the surface.
4.1.3 Deep -Sump, Hooded Catch Basins
Inspection Frequency: Quarterly
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Section 4 Stormwater Management System Tighe&Bond
Special Inspection Event(s): Rainfall greater than 0.5 inches
Deep sump catch basins should be inspected at least four times per year. The Visual
inspection should ascertain that the catch basin is functioning properly (i.e. no blockages
or obstructions to the outlet and/or hood) and to measure the amount of solid materials
that have accumulated in the sump. This can be done with a calibrated dipstick, tape
measure or other measuring instrument so that the depth of deposition in the sump can
be tracked. Inspections should be completed visually from the ground level. Deep sump
catch basins should be cleaned four times per year or whenever the depth of the
sediment is greater than or equal to one half the depth from the bottom of the invert of
the lowest pipe in the basin. Cleanings should also be conducted at the end of the
foliage and snow -removal seasons. Clamshell buckets can be used to remove sediment.
However, vacuum trucks will remove more trapped sediment, are more expedient, and
are less likely to damage hoods on outlet pipes. Disposal of sediment removed from
catch basins must be disposed of in accordance with local, state and federal
requirements.
4.1.4 Proprietary Water Treatment Devices
Inspection Frequency: Per manufacturer recommendations
Special Inspection Event(s): Rainfall greater than 0.5 inches
Structural Water Quality Units (WQU) will be observed in accordance with manufacturer
recommendations. Units are to be cleaned as directed by the manufacturer.
Manufacturer recommended O&M requirements are provided in Appendix F.
4.1.6 Surface Infiltration Basin
Inspection Frequency: Bi-annually
Special Inspection Event(s): Rainfall greater than 0.5 inches
Surface infiltration basins should be inspected bi-annually for standing water. If standing
water is observed for longer than 72 hours, a pump should be placed in the basin and
discharged through the outlet pipe. After the system is dewatered, it should be observed
by a Professional Engineer. A Professional Engineer should provide an opinion as to why
the infiltrations basin is not draining and provide recommendations to restore infiltration
capacity to the system. Additionally, infiltration basins shall be observed to identify
depths of sediment and occurrence of debris which would impact functionality. The
outlet control structure, if applicable, shall be observed for signs of clogging during
storm events and erosion. Any trash or debris encountered shall be removed.
If the basin is equipped with a Sediment Forebay, inspect the forebay monthly to
observe sediment depth, and to identify signs of rilling and gullying an repair as needed.
Forebays should be mowed as needed, with grass height no greater than 6 inches.
Remove accumulated sediment quarterly, and when sediment depth is between 3 to 6
feet. After sediment removal, reseed by incorporating practices such as hydroseeding
with a tackifier or erosion control blanket.
4.1.7 Infiltration Trenches
Inspection Frequency: Bi-annually
Special Inspection Event(s): Rainfall greater than 0.5 inches
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Section 4 Stormwater Management System Tighe&Bond
Perform preventive maintenance at least twice a year. Inspect and clean pretreatment
BMPs every six months and after every major storm event (2 year return frequency).
Check inlet and outlet pipes to determine if they are clogged. Remove accumulated
sediment, trash, debris, leaves and grass clippings from mowing. Remove tree
seedlings, before they become firmly established. Because infiltration trenches are prone
to failure due to clogging, it is imperative that they be aggressively maintained on a
regular schedule.
4.1.13 Stone End Protection (Outfalls)
Inspection Frequency: Bi-annually
Special Inspection Event(s): Rainfall greater than 0.5 inches
Emergency spillways should be inspected twice a year as well as after every major
storm, for slope integrity, soil moisture, vegetated health, soil stability, soil compaction,
soil erosion, ponding and sediment accumulation. If the rip rap has been displaced,
undermined or damaged, it should be replaced immediately. The channel immediately
below the outlet should be checked to see that erosion is not occurring. The downstream
channel will be kept clear of obstructions, such as fallen trees, debris, leaves and
sediment that could change flow patterns and/or tail water depths in pipes. Repairs must
be carried out immediately to avoid additional damage to the outlet protection apron.
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Section 5 Operation and Maintenance Log
Form
Person conducting Inspection:
Reason for Inspection (Routine / Significant Rainfall):
Stormwater Management System Components:
Vegetated Surface
Component inspected during this inspection
Any Repair Necessary
Other Comments
Driveway and Walkway Sweeping
Component inspected during this inspection
Any Repair Necessary
Other Comments
Deep -Sump Hooded Catch Basins
Component inspected during this inspection
Any Repair Necessary
Other Comments
Proprietary Water Quality Units
Component inspected during this inspection
Any Repair Necessary
Other Comments
Infiltration Basins
Component inspected during this inspection
Any Repair Necessary
Other Comments
Culvert and Stone End Protection
Component inspected during this inspection
Any Repair Necessary
Other Comments
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Section 6
Snow Management & De -Icing
Snow removal will occur along areas where the proposed site improvements occur. Snow
storage should not be in or adjacent to wetland areas nor block drainage to surface
inlets (e.g. catch basins).
Applications of chemical de-icing may be applied along with sand for the roads, main
entrances, stop sign areas, and sidewalks. Apply only as needed using minimum
quantities. Small quantities of deicers may be mixed with sand or sprayed on hard to
maintain areas.
Sweep or clean up accumulated sand, sidewalks, steps, and roads as soon as possible
after the road surface clears.
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Section 7
Estimated O&M Budget
The following estimated O&M Budget includes the inspections and maintenance activities
previously described on an annual basis.
Maintenance
Quantity
Frequency
Unit Cost
Annual Cost
Component
er ear
Vegetated Surfaces
1
4
$100
$100
Street Sweeping
1
4
$250
$250
Catch Basin
4
4
$250
$1,000
Inspection
Catch Basin
4
2
$1,000
$4,000
Sediment Removal
Surface Infiltration
1
2
$500
$500
Basins
System Outfalls
2
2
$250
$500
Proprietary
1
3
$500
$500
Treatment Devices
Total Annual Estimated Budget
$6,950
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Pollution Prevention and Stormwater Management OM Plan.doc
Long Term O&M Plan 7-1
APPENDIX G
Tighe&Bond
Illicit Discharge Compliance Statement
Project Location: 127 Whites Path, South Yarmouth, MA 02664
Illicit discharges to the stormwater management system are discharges that are not
entirely comprised of stormwater. Illicit discharge does not include discharges from the
following activities or facilities: firefighting, water line flushing, landscape irrigation,
uncontaminated groundwater, potable water sources, foundation drains, air conditioning
condensation, footing drains, individual resident car washing, flows from riparian
habitats and wetlands, dechlorinated water from swimming pools, water used for street
washing, and water used to clean residential buildings without detergents.
To the best of my knowledge, I am not aware of any existing illicit discharges located at
the Project Location and will abandon or remove such illicit discharges/connections in
the future, if found.
Signature: //JI
Printed Name & Title: Matthew T. Wozniak, PE, Lead Environmental Engineer
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Discharge Statement.doc
South Yarmouth LNG Project
Stormwater Management Report