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HomeMy WebLinkAbout20250121_NOI_CCS_Part 7 Attachment I Eversource Best Management Practices Manual Best Management Practices Manual for Massachusetts and Connecticut APRIL 2022 Prepared for: Eversource Energy Environmental Licensing and Permitting Group CONSTRUCTION & MAINTENANCE ENVIRONMENTAL REQUIREMENTS TABLE OF CONTENTS Table of Contents i Section 1 Introduction 1.1 Purpose ........................................................................................1-1 1.2 Scope and Applicability ...................................................................1-1 1.3 Definitions .....................................................................................1-1 1.4 Acronyms and Abbreviations ............................................................1-4 1.5 BMP References .............................................................................1-5 Section 2 Project Planning 2.1 Regulated Areas .............................................................................2-1 2.1.1 Types of Wetlands ................................................................ 2-1 2.1.2 Rare Species........................................................................ 2-2 2.1.3 Historical/Cultural ................................................................ 2-3 2.2 Meetings .......................................................................................2-3 2.3 Site Staging and Parking .................................................................2-3 2.4 Construction Monitoring ..................................................................2-3 2.5 Signage/Limit of Boundaries ............................................................2-3 Section 3 Construction Considerations 3.1 Avoidance and Minimization .............................................................3-1 3.2 Rare Species Habitat ......................................................................3-1 3.3 Hiking Trails ..................................................................................3-2 3.4 Work on State-owned land in Connecticut .........................................3-3 3.5 Historic/Cultural Resources ..............................................................3-3 3.5.1 Stone Walls ......................................................................... 3-3 3.5.2 Unanticipated Discoveries ...................................................... 3-5 3.6 Human Remains .............................................................................3-5 3.7 Vernal Pools ..................................................................................3-5 3.7.1 Certified Vernal Pools (MA) .................................................... 3-6 3.8 Access Roads .................................................................................3-6 3.8.1 New Access Roads ................................................................ 3-7 3.8.2 Existing Access Roads ........................................................... 3-7 3.8.3 Best Management Practices – New Access Roads ...................... 3-9 3.8.4 Construction in Wetlands ..................................................... 3-15 3.8.5 Watercourse Crossings ........................................................ 3-20 3.9 Slope Excavation .......................................................................... 3-24 3.10 Vegetation Removal and Preservation ............................................. 3-24 3.10.1 ROW Vegetation and Eastern Box Turtle (EBT) – MA only ........ 3-25 3.10.2 ROW Vegetation and Other Protected Turtles ......................... 3-25 3.10.3 Preservation of Existing Vegetation ....................................... 3-27 Table of Contents ii 3.10.4 Invasive Plant Species ........................................................ 3-27 3.11 Work Pads ................................................................................... 3-32 3.11.1 De-Energized and Energized ................................................ 3-32 3.12 Structure-Related Work ................................................................ 3-33 3.12.1 Wetland ............................................................................ 3-33 3.13 Underground Cable and Gas Piping-Related Work ............................. 3-36 3.14 Construction Material along the ROW .............................................. 3-38 3.15 Winter Construction ...................................................................... 3-38 3.15.1 Snow Management ............................................................. 3-38 3.15.2 De-Icing ............................................................................ 3-39 3.15.3 Snow and Ice Management on Construction Mats ................... 3-39 3.16 Dust Control ................................................................................ 3-39 3.16.1 Soil Stockpile Management .................................................. 3-40 3.16.2 Stockpiles on Construction Mats ........................................... 3-40 3.16.3 Regulated Soils Management ............................................... 3-40 3.16.4 Best Management Practices – Soil Stockpile Management ........ 3-41 3.17 Anti-Idling Laws ........................................................................... 3-41 3.17.1 Connecticut ....................................................................... 3-41 3.17.2 Massachusetts ................................................................... 3-41 Section 4 Inspection and Maintenance 4.1 During Construction ........................................................................4-1 4.1.1 Maintenance of Erosion and Sedimentation Controls ................. 4-1 4.1.2 Rapid Wetland Response Restoration ...................................... 4-1 4.1.3 Vehicle Storage and Refueling ................................................ 4-1 4.1.4 Spills .................................................................................. 4-2 4.1.5 Post-Construction ................................................................. 4-2 Section 5 Rehabilitation and Restoration 5.1 Restoration ....................................................................................5-1 5.1.1 Seed Mixes .......................................................................... 5-1 5.1.2 Upland ................................................................................ 5-1 5.1.3 Wetland/Watercourses .......................................................... 5-2 5.2 Private Property .............................................................................5-3 5.2.1 Improved Areas ................................................................... 5-3 5.2.2 Overall Work Site ................................................................. 5-3 5.2.3 Material Storage/Staging and Parking Areas ............................ 5-3 5.3 Work in Agricultural Lands ...............................................................5-4 Table of Contents iii Appendices A BMP Typical Details Construction A01 Construction Entrance Track Pad A02 Water Bars A03 Vegetated Swales A04 AlturnaMAT® A05 Construction Mat (Wetland Crossing) A06 Construction Mat (Air Bridge) A07 Construction Mat Anchoring A08 Permeable Road A09 Temporary Construction Culvert A10 Permanent Open Bottom Box Culvert A11 Arch Culvert A12 Pole Ford A13 Construction Mat Work Pad (Live Line Work) A14 Construction Mat Work Pad (De-Energized Line Work) A15 Concrete Wash Out A16 Road Trench (Duct Bank) A17 Road Trench (6-Way Duct Bank) A18 Tree Protection Soil Stockpile Management A19 Soil Stockpile Management Erosion / Sedimentation Controls A20 Topsoil Segregation A21 Straw Bale Barrier A22 Silt Fence A23 Syncopated Silt Fence A24 Reinforced Silt Fence Table of Contents iv A25 Erosion Control Blankets A26 Straw Wattle / Mulch Log A27 Straw Wattle (on Slope) A28 Compost Filter Tube A29 Turbidity Curtain A30 Catch Basin Inlet Protection (Straw Bales) A31 Catch Basin Inlet Protection (Silt Sack) A32 Loam and Seed A33 Straw Mulch A34 Coir Log A35 Level Spreader A36 Check Dams A37 Trench Breakers Water Control A38 Sediment Trap A39 Dewatering Basin A40 Dewatering Basin (Filter Bag) A41 Dewatering Basin (Frac Tank) A42 Coffer Dam and Stream Flow Bypass (gravity) A43 Coffer Dam and Stream Flow Bypass (pumping) B Applicable Regulations in Connecticut C Applicable Regulations in Massachusetts D Example Frac-Out Plan SECTION 1 Eversource Best Management Practices Manual 1-1 Section 1 Introduction 1.1 Purpose As a matter of Eversource Energy (herein, “Eversource”) policy with regard to environmental stewardship and in accordance with local, state, and federal regulations, all construction and maintenance projects shall use environmentally sound best management practices (BMPs) to minimize or eliminate environmental impacts that may result from construction activities. Regardless of whether a specific permit is needed for the work, construction and maintenance projects must f ollow internal environmental performance standards, which is the purpose of these BMPs. In many cases, maintenance activities are exempt from regulatory authorization. Permits are usually required for new work. Contractors will be provided with copies of any project- specific permits and will be required to adhere to any and all conditions of the permit(s). Project-specific permit conditions may supersede the BMPs outlined in this manual. However, where certain construction elements are not addressed by per mit conditions, or where permitting is not required, or for emergency situations where obtaining a permit before the work occurs may not be feasible, these BMPs shall be considered as Eversource’s standards. In some cases, and at the discretion of the Eversource Environmental Licensing and Permitting staff, the BMPs presented herein may be modified to be more appropriate for site-specific conditions. 1.2 Scope and Applicability These BMPs primarily address the disturbance of soil, water, and vegetation incidental t o construction within on- and off-road utility corridors, substations, including the establishment of access roads and work areas, within rights of way (ROWs) and on private property, in and near wetlands, watercourses, or other sensitive natural areas (such as protected species), including storm drain systems (e.g., catch basins). Types of construction include, but are not limited to, installation or maintenance of underground and overhead utilities, access road repair/improvement or construction, and upgrades or maintenance of substations and other facilities. Other common construction issues such as noise, air pollution, oil spill procedures, handling of contaminated soils, and work safety rules are addressed in the Eversource Energy Contractor Work Rules and related appendices. 1.3 Definitions The following definitions are provided to clarify use of common terms throughout this document. Best Management Practice (BMP): A means to reduce and minimize impact to natural resources. Casing: A galvanized steel corrugated pipe that serves as the form for a utility structure foundation. Section 1 Introduction Eversource Best Management Practices Manual 1-2 Emergency Projects: Actions needed to maintain the operational integrity of the system or activities necessary to restore the system and affected facilities in response to a sudden and unexpected loss of electric or gas service or events that affect public health and safety. Embedded Culvert: A culvert that is installed in such a way that the bottom of the structure is below the stream bed and there is substrate in the culvert. Environmentally Sensitive Areas: An area containing natural features, cultural resources, or ecological functions of such significance to warrant protection. Some examples are rivers, streams, ponds, lakes, wetlands, rare species habitat, water supply protection areas, archaeological sites, parks, and agricultural land. Erosion Control: A measure to prevent soil from detachment and transportation by water, wind, or gravity. Existing Access Roads: Previously permitted or grandfathered access roads that are used to access structures that are clearly visible or can be found by mowing or by the presence of road materials in soil cores. Grubbing: A site preparation method that is used to clear the ground of roots and stumps. Intermittent Watercourse: An intermittent watercourse, or stream, is broadly defined as a channel that a flowing body of water follows at irregular intervals and does not have continuous or steady flow. Regulatory definitions for intermittent watercourses are: • Connecticut – Per the Connecticut Inland Wetland and Watercourses Act, intermittent watercourses are delineated by a defined permanent channel and bank and the occurrence of two or more of the following characteristics: (A) Evidence of scour or deposits of recent alluvium or detritus, (B) the presence of standing or flowing water for a duration longer than a particular storm incident, and (C) the presence of hydrophytic vegetation. • Massachusetts – Under the Massachusetts Wetlands Protection Act (MAWPA), a jurisdictional intermittent watercourse is defined as a body of running water which moves in a definite channel in the ground due to a hydraulic gradient, does not flow throughout the year, and which flows within, into or out of an area subject to protection under the MAWPA. Intermittent watercourses upgradient of any Bordering Vegetated Wetlands or Ponds are not jurisdictional under the MAWPA. A watercourse can be determined to be intermittent if it me ets MAWPA criteria with regard to its depiction on the most current USGS topographic map of the area (i.e., shown as intermittent or not shown), and watershed size and predicted flow rates as determined by the USGS StreamStats method or documented observations of no flow at least once per day over the course of four days in any consecutive 12 - month period barring drought conditions, withdrawals, or other human-made flow reductions or diversions (subject to conservation commission and/or M assDEP review and approval). Limit of Work/Disturbance: The boundaries of the approved project within regulated areas. All project related activities in regulated areas must be conducted within the approved limit of work/disturbance. The limit of work/disturbance should be depicted on the approved permit site plans, which may require the limits to be survey located and identified in the field by flagging, construction fencing, and/or perimeter erosion controls. Low Ground Pressure Vehicle: Vehicles that have a lesser impact on an environmentally sensitive area due to the vehicle being smaller, lighter, or different in another way than a vehicle which would have a greater impact. Low ground pressure is Section 1 Introduction Eversource Best Management Practices Manual 1-3 measured in pounds per square inch (psi) when loaded and as defined by the US Army Corps of Engineers (ACOE). CT = < 3 psi MA = < 3 psi Low impact vehicles could include off -road vehicles (ORVs) or all-terrain vehicles/ utility vehicles (ATVs/UTVs), tracked vehicles with low ground pressure, or vehicles with oversized balloon-type tires. Maintenance Projects: Typically consist of activities limited to the repair and/or replacement of existing and lawfully located utility structures and/or facilities where no substantial change in the original structure or footprint is proposed. Maintenance activities also include vegetation management. Minimization: Causing as little disturbance to an area as practicable during construction. New Construction: Construction of new transmission or distribution facilities that previously did not exist or construction that substantially modifies existing facilities. All new (and existing) construction projects are required to go through a full permit review by Eversource Environmental Licensing and Permitting. Pre-Construction Notification (PCN): Project activities that do not qualify for Self- Verification (SV) or where otherwise required by the terms of the Massachusetts (MA) and Connecticut (CT) General Permits (GPs) must submit a PCN and obtain written verification before starting work in ACOE jurisdiction. Refer to MA and CT GP s for PCN thresholds. Projects that cannot be completed under a PCN must file for an Individual Permit with the ACOE. In CT, for coastal projects, notification is provided to ACOE by the CT Department of Energy and Environmental Protection (CT DEEP), Office of Long Island Sound Programs (OLISP) or by applicants as necessary. Written approval from ACOE is required. Protected Species: Species named and protected under the Massachusetts Endangered Species Act (MESA) regulations and/or the Connecticut Endangered Species Act (C.G.S. §§ 26-303 through 26-315). Rare Species: See Protected Species. Restoration: To return a disturbed area to its former, original or unimpaired condition. A site is considered fully restored when it has returned (as closely as practicable) to its original state. Restoration of disturbed areas should occur as soon as practicable following the completion of activities at that location. Revegetation: Establishment of plant material for temporary or permanent soil stabilization. Right of Way (ROW): A pathway, road, or corridor of land where Eversource has legal rights (either fee ownership, lease, or easement) to construct, operate, and main tain an electric power line and/or natural gas pipeline. Sediment Control: The practice of managing the erosion of soil materials mobilized by water, typically stormwater runoff, on-site for the purpose of protecting nearby wetland and water resources. Self-Verification (SV): Activities that are eligible for SV are authorized under the MA and CT GPs and may commence without written verification from the ACOE provided the prospective permittee has: i. Confirmed that the activity will meet the terms and conditions of applicable MA and CT GPs. Section 1 Introduction Eversource Best Management Practices Manual 1-4 ii. Submitted the Self-Verification Notification Form (SVNF) to the ACOE. In CT, coastal projects do not require filing of a SVNF. ACOE relies on CT DEEP submittals. Sensitive Environmental Area: For the purposes of this BMP Manual, this term shall be inclusive of all wetlands, streams, waterways, waterbodies, buffer zones, rare species habitat, and historical/cultural resources. Stabilization: A system of permanent or temporary measures used alone or in combination to minimize erosion from disturbed areas. Work: For the purposes of this BMP Manual, any form of temporary or permanent draining, dumping, damming, discharging, excavating, filling or grading; the erection, reconstruction, replacement or expansion of any buildings or structures; the driving of piles; the construction or improvement of roads and other ways; the changing of run -off characteristics; the intercepting or diverging of ground or surface water; the installation of storm drain systems (e.g., catch basins); the discharging of pollutants; the destruction of plant life; and any other changing of the physical characteristics of land including, but not limited to: on- and off-road utility corridors and substations. Types of work include but are not limited to the installation or maintenance of underground and overhead utilities, substations and other facilities. 1.4 Acronyms and Abbreviations The following acronyms and abbreviated are provided to clarify use of common terms throughout this document. All-terrain Vehicle ATV Best Management Practice BMP Certified Vernal Pool CVP Connecticut CT Connecticut Department of En ergy & Environmental Protection CT DEEP Connecticut Department of Transportation ConnDOT Connecticut General Statute Conn. Gen. Stat. Cross-Linked Polyethylene XLPE Eastern Box Turtle EBT Environmental Affairs Department EAD Eversource Energy Eversource General Permits GPs Geographic Information System GIS High-Pressure Fluid-Filled HPFF Horizontal Directional Drilling HDD Kilovolt kV Massachusetts MA Massachusetts Department of Agriculture MA DAR Massachusetts Department of Conservation and Recreation MA DCR Section 1 Introduction Eversource Best Management Practices Manual 1-5 Massachusetts Department of Environmental Protection MassDEP Massachusetts Endangered Species Act MESA Massachusetts Wetlands Protection Act MAWPA Massachusetts General Law M.G.L. Natural Diversity Database NDDB Natural Heritage and Endangered Species Program NHESP New England Cottontail NEC Off-Road Vehicle ORV Outstanding Resource Water ORW Pounds per Square Inch psi Pre-Construction Notification PCN Right of Way ROW Self-Verification SV Self-Verification Notification Form SVNF Species spp. Time of Year TOY United States U.S. United States Army Corps of Engineers ACOE United States Department of Agriculture USDA United States Geologic Survey USGS Utility Vehicle UTV Vegetation Management Plan VMP 1.5 BMP References The following table lists the public guidance documents utilized during the preparation of this BMP manual. Refer to these documents for additional information. BMP References General Best Management Practices (BMPs) Manual for Access Road Crossings of Wetlands and Waterbodies, EPRI, Palo Alto, CA (2002) 1005188. Gas Research Institute. Horizontal Directional Drilling Best Management Practices Manual (2002) ENSR Corporation, Westford, MA and Trenchless Engineering Corp., Houston, TX. Connecticut Connecticut Department of Transportation (ConnDOT). ConnDOT Drainage Manual (October 2000) http://www.ct.gov/dot/cwp/view.asp?a=1385&Q=260116 Section 1 Introduction Eversource Best Management Practices Manual 1-6 BMP References Connecticut Standard Specifications for Roads, Bridges and Incidental Construction, FORM 816 (2004) http://www.ct.gov/dot/cwp/view.asp?a=3609&q=430362 Connecticut Department of Energy & Environmental Protection. Connecticut Guidelines for Erosion and Sediment Control. (2002) http://www.ct.gov/deep/cwp/view.asp?a=2720&q=325660&deepNav_GID=1654%20 Connecticut Department of Energy & Environmental Protection, Bureau of Natural Resources, Division of Forestry. Best Management Practices for Water Quality While Harvesting Forest Products (2012) https://portal.ct.gov/- /media/DEEP/forestry/best_management_practices/BestPracticesManualpdf.pdf Regulations of Connecticut State Agencies (RCSA). Control of Particulate Matter and Visible Emissions. Section 22a-174-18. https://eregulations.ct.gov/eRegsPortal/Browse/RCSA/Title_22aSubtitle_22a - 174Section_22a-174-18/ Massachusetts Commonwealth of Massachusetts Department of Public Works Standard Specifications for Highways and Bridges (2020) https://www.mass.gov/doc/2020-standard-specifications-for-highways-and- bridges/download Massachusetts River and Stream Crossing Standards (Revised March 1, 2011) https://www.nae.usace.army.mil/Portals/74/docs/regulatory/StreamRiverContinuity/MA_RiverStrea mCrossingStandards.pdf Massachusetts Erosion and Sediment Control Guidelines for Urban and Suburban Areas. Original Print: March 1997. Reprint: May 2003. https://www.mass.gov/doc/complete- erosion-and-sedimentation-control-guidelines-a-guide-for-planners-designers-and/download The Massachusetts Unpaved Roads BMP Manual (Winter 2001) https://www.mass.gov/doc/unpaved-roads-bmp-manual/download The Massachusetts Anti-Idling Law. M.G.L. Chapter 90, Section 16A and 310 CMR 7.11. https://www.mass.gov/doc/massdep-faq-the-massachusetts-anti-idling-law/download SECTION 2 Eversource Best Management Practices Manual 2-1 Section 2 Project Planning After undergoing an initial screening review by the department conducting the proposed project, if sensitive environmental areas are identified, the project is required to go through a permit review by Eversource Environmental Licensing and Permitting. The permit review process is supported by Geographic Information Systems (GIS) or a similar program that references the most current spatial data for the project areas in question. Through the GIS review process various geo-processing tools are used to compose maps and provide a spatial reference to environmentally sensitive areas. In consultation with Eversource Environmental Licensing and Permitting, the Project Engineer, permitting specialist, or other project planner should determine regulatory jurisdiction and which (if any) environmental permits or approvals are required before starting any project. Questions regarding which activities may be conducted in regulated areas or within environmentally sensitive areas should be referred to Eversource Environmental Licensing and Permitting. Summaries of potentially applicable laws and regulations are provided in Appendices B and C of this document. Eversource employs a best practice mitigation hierarchy to 1) avoid environmental impacts wherever possible, followed by 2) minimization of environmental impacts where they cannot be avoided, and 3) mitigating and restoring any environmental impacts where necessary. 2.1 Regulated Areas 2.1.1 Types of Wetlands Wetland areas common to New England and common to both Connecticut and Massachusetts include, but are not limited to, the following: Forested Wetlands Forested wetlands are wetlands that ar e dominated by trees that are 20 feet or taller. These wetlands are typically drier with standing water typically occurring during periods of high precipitation, seasonally high groundwater, snowmelt, and runoff (e.g., early spring through mid-summer). Tree species typical of this type of wetland include red maple (Acer rubrum) and eastern hemlock (Tsuga canadensis). “Pit and mound” topography is common in forested wetlands, where mature trees grow on the higher and drier mounds and obligate wetland species are found in the lower pits. Scrub-Shrub Wetlands Scrub-shrub wetlands are dominated by woody vegetation less than 20 feet tall and may include peat bogs. Typical bog species include leatherleaf (Chamaedaphne calyculata), cotton grasses (Eriophorum sp.), cranberry (Vaccinium macrocarpon, V. oxycoccus), and black spruce (Picea mariana). Other non-bog scrub-shrub wetlands are characterized by buttonbush (Cephalanthus occidentalis), alders (Alnus spp.), dogwoods (Swida spp.), and arrowwoods (Viburnum spp.). Section 2 Project Planning Eversource Best Management Practices Manual 2-2 Marshes Marshes are dominated by erect, herbaceous vegetation and appear as grasslands or stands of reedy growth. These wetlands are commonly referred to by a host of terms, including marsh, wet meadow, or fen. These areas are flooded all or most of the year and, in New England, tend to be dominated by cattails (Typha spp.). Wet Meadows Typical wet meadow species include grasses such as bluejoint (Calamagrostis canadensis) and reed canary grass (Phalaris arundinacea), sedges (Carex spp.) and rushes (Juncus spp.), and various other forbs such as Joe-Pye-weeds (Eutrochium spp.) and asters (Aster spp.). Floodplains A floodplain is generally defined as an area of low-lying ground adjacent to a stream or river that is formed mainly of river sediments and is subject to inundation from floodwaters. State-specific regulatory definitions vary and are described as follows: • In Connecticut, areas that contain alluvial or floodplain soils are regulated as wetlands. These areas may flood so infrequently or be so freely drained that hydrophytic vegetation and hydric soils are not present. Soils in these areas must be examined carefully to determine whether well drained alluvial or floodplain soils are present. • In Massachusetts, a floodplain is a type of wetland resource area that floods following storms, prolonged rainfall, or snowmelt. There are three types of floodplain areas protected under the MAWPA: coastal areas, areas bordering rivers and streams, and isolated depressions that flood at least once a year. Streams A stream is any natural flowing body of water that empties to any ocean, lake, pond or other river. Perennial streams, or rivers, have flows throughout the year. Intermittent streams do not have surface flows throughout the year, though surface water may remain in isolated pockets. Vernal Pools Vernal pools are typically contained basin depressions lacking permanent aboveground outlets. These areas fill with water with the rising water table of fall and winter and/or with the meltwater and runoff of winter and spring snow and rain. The pools contain water for a few months in the spring and early summer. Due to periodic drying cycles, vernal pools do not support breeding fish populations and can thus serve as breeding grounds for a variety of organisms, including some rare and/or protected species of frogs and salamanders. 2.1.2 Rare Species Utility ROWs within Connecticut and Massachusetts overlap with, and in some circumstances create or enhance, habitat of rare/protected species of plants, vertebrate and invertebrate animals. Special requirements may need to be evaluated as part of new construction and/or some maintenance activities. Section 2 Project Planning Eversource Best Management Practices Manual 2-3 2.1.3 Historical/Cultural Other regulated factors taken into consideration during the project planning process include the presence of protected (i.e., threatened or endangered) specie s, non- native, invasive plant species and/or historical/cultural resources. Special requirements may need to be evaluated as part of new construction and/or some maintenance activities. 2.2 Meetings A pre-construction meeting is typically held prior to the commencement of all work with the purpose to appoint responsible parties, discuss timing of work, and further consider options to avoid and/or minimize disturbance to sensitive areas. The meeting confirms that there is consensus on work methods and responsibilities and ensure s that tasks will be fulfilled with as little disturbance to the environment as practicable. These meetings can occur on or off-site and should include all the applicable stakeholders (i.e., Eversource, contractors, consultants, inspectors and/or monitors, and regulatory agency personnel). A short and less formal briefing should suffice for smaller maintenance projects. 2.3 Site Staging and Parking During the project planning and permitting process, locations should be identified for designated crew parking areas, material storage, and staging areas. Where possible, these areas should be located outside of buffer zones, watershed protection areas, and other environmentally sensitive areas. Any proposed locations should be evaluated for all sensitive receptors and for new projects requiring permitting, should be incorporated onto permitting and access plans. 2.4 Construction Monitoring Construction projects require environmental monitoring, which can be conducted either internally or by consultants. Some permitted projects require oversight by designated and pre-approved compliance monitors. Environmental monitoring is a way to keep a chronological record of pre-construction site conditions, progress, and changes that are made, as well as to document issues and authorized solutions. If work will occur in a sensitive environmental area, permit conditions may dictate that construction be monitored by a qualified and pre-approved wetland or wildlife specialist. 2.5 Signage/Limit of Boundaries Where appropriate, wetland delineation flagging or signage shall be installed that makes clear where critical boundaries (i.e., the limits of jurisdictional wetland resource areas, rare species habitat, and/or historical/cultural resources) and setbacks occur. Appropriate signage shall also be installed to indicate regulatory authorization by agencies and to prohibit certain uses on ROWs, such as ORV traffic. Where appropriate, signage shall be installed along sediment and erosion control barriers at appropriate intervals, heights, and sizes to ensure that the presence and location of said barriers is clear to construction personnel d uring deep snow or other low visibility conditions. Inspection and maintenance of this signage shall be conducted on a regular basis to ensure effectiveness. Section 2 Project Planning Eversource Best Management Practices Manual 2-4 Examples of signage at wetlands SECTION 3 Eversource Best Management Practices Manual 3-1 Section 3 Construction Considerations This section addresses BMPs specific to construction of new access roads, repair of existing access roads, the installation of work pads, structure-related work, and soil stockpile management. Information regarding recommended erosion and sedimentation controls or stormwater controls is also discussed. Please refer to Appendix A for typical details and representative photographs of BMPs used for erosion and sedimentation control and water diversion during construction. During all project activities (e.g., maintenance, new construction), federal, state, and local regulatory authorities require steps be taken to avoid, minimize, and/or mitigate disturbance to the environment. Sensitive environmental areas should be avoided whenever practicable. However, some projects may require entrance into these areas in order to perform work. This section discusses measures that should be taken to minimize disturbance to if work must occur within sensitive environmental areas. BMPs were developed to aid in this process and should be carefully selected and implemented based on the proposed activities and the nature of sensitive area(s) encountered at each site. Proper selection of BMPs should take into consideration the project goals, permit requirements, and site-specific information. Once an assessment of the area is made and requirements of the project are established, all BMPs should be considered and implemented as appropriate. 3.1 Avoidance and Minimization Avoidance and minimization should always be considered before beginning any construction or maintenance project. Eversource and their contractors should utilize appropriate measures to avoid construction impacts to sensitive environmental areas including, but not limited to: wetlands, waterways, rare species habitats, known below and above ground historical/archeological resources, and other environmentally sensitive areas. Use existing ROW access whenever practicable. Keep to approved routes and roads and do not widen or deviate from them. Consult with the Eversource Environmental Licensing and Permitting Group, when avoidance is not practicable, to determine measures to minimize the extent of construction impacts. Alternate access routes and/or staging areas that will minimize construction impacts to the natural environment may be considered. 3.2 Rare Species Habitat Eversource Environmental Licensing and Permitting coordinates with state and local agencies when work is within areas designated as rare and/or sensitive species habitat. In order to protect these resources in Connecticut, the following must be reviewed: • Natural Diversity Database (NDDB) area mapping. • Critical Habitat mapping. • Eversource’s New England Cottontail (NEC) BMP map. • Prior NDDB Determinations. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-2 The NDDB mapping is updated approximately every six months and is posted on the State’s GIS data download webpage. The Critical Habitat mapp ing is less frequently updated and also on the State’s GIS data download page. Eversource’s NEC BMP map and mapping which depicts prior NDDB Determinations shall be provided through Eversource Environmental Licensing and Permitting. In Massachusetts, Eversource has an annual Operations and Management Plan (OMP) which is updated and renewed at the start of each calendar year with the Natural Heritage Endangered Species Program (NHESP) which designates Priority Habitat (PH) in the State. All work in PH requires review of and compliance with the OMP which may include consultation with NHESP. The OMP establishes guidelines for work within known rare species habitat based on the type of species presence. These guidelines may include time of year (TOY) restrictions or similar measures to avoid impacts to rare species. Regardless of the State in which construction is taking place, the following shall be employed in all mapped, State-listed species and designated Critical Habitat areas: • Make every effort to avoid impacts to known populations of State-listed plants and other stationary resources. • Limit permanent impact through the use of temporary construction matting as opposed to gravel for access road and work pad construction. • If State-listed resources cannot be avoided, mitigation planning shall be discussed with Environmental Licensing and Permitting. • Consider time-of-year (TOY) restrictions to avoid impact to sensitive resources during critical life stages including but not limited to nesting season for ground and shrub nesting birds, pup rearing season for bats (if tree removal is necessary), flowering and seeding times for State-listed plants. Certain species, including the timber rattlesnake (Crotalus horridus), are one of the few venomous species in New England which can be a threat to worker safety. Protection measures provided by the respective State agency shall be followed and may require snake sweeps by a qualified herpetologist, contractor education, and field demarcation of hibernacula/known rattlesnake dens. 3.3 Hiking Trails The following practices shall be implemented in the event project areas intersect or overlap with recreational hiking trails. • Avoid using hiking trails as access roads or access routes for vehicles and equipment. • If a hiking trail must be used for vehicle or equipment access coordination with Eversource Vegetation Management Compliance or Oversight staff and/or Eversource Environmental Licensing and Permitting staff is required prior to use. • Utilize existing access roads to cross hiking trails to the maximum extent practicable. • If no existing access roads exist and a hiking trail must be crossed, minimize trail crossings by designating one location for use by equipment. • Signs, barriers, spotters or other means to alert the public to the work shall be Section 3 Construction Considerations Eversource Best Management Practices Manual 3-3 implemented. • Stockpiling logs and other cut material within 25 feet of hiking trails is not allowed unless approved by Eversource Vegetation Management Compliance or Oversight staff. • Spreading wood chips on hiking trails is not allowed unless approved by Eversource Vegetation Management Compliance or Oversight staff. • At the end of each workday all cut material must be removed from hiking trails. • As soon as possible after work is complete disturbed portions of hiking trails shall be returned as close to pre-construction condition as possible. This may include hand raking, hand cutting of stumps and/or hand removal of cut vegetation. • If any trees that are marked for trail navigation must be cut, the property manager or trail maintainer must be notified. • Posts or other markers that are used for trail navigation shall be protected at all times. Replacement in kind shall be completed by the contractor if disturbed or damaged during completion of the work. 3.4 Work on State-owned land in Connecticut For all work on State of Connecticut-owned land as depicted on the “DEEP Property” data layer available through the State’s GIS data download page, matting shall be employed to the greatest extent possible. Gravel access roads and work pads shall only be installed when terrain prohibits the installation of matting. All work must be coordinated through Eversource Environmental Licensing and Permitting for acquisition of necessary authorization prior to the start of construction on State-owned properties. 3.5 Historic/Cultural Resources Historic and cultural resources are diverse and include, but are not limited to, archaeological sites, historic structures, historic districts, stone walls, and ceremonial stone landscapes. Construction activities near or within significant resources are subject to restrictions outlined in any site or project-specific avoidance/protection plans. The locations of archaeological sites and other sensitive resource s such as ceremonial stone landscapes and burials are considered confidential and may only be disclosed on a need - to-know basis. 3.5.1 Stone Walls Stone walls can be considered significant resources for a number of reasons including unique construction methods, their function as a property boundary, their association with other historic resources such as archaeological sites or farmsteads, and/or their importance to the underlying landowner(s). Non-impact methods of managing work and access near stone walls should always be prioritized and removal, dismantlem ent, or other alterations to stone walls should be avoided, when possible. Non -impact methods of managing work near stone walls include: • Avoiding the stone wall altogether - This may involve re-routing an access road or selecting a new access point. Care should be taken not to incur additional impacts to other sensitive environmental areas (e.g., wetlands or rare species habitat). • Traversing the wall through an existing breach - In this scenario, the breach is Section 3 Construction Considerations Eversource Best Management Practices Manual 3-4 used as-is and the breach is not widened or expanded in any way. • Traversing the wall using timber matting to temporarily bridge over the wall (e.g., “air bridge”) - Although the construction of individual air bridges will vary depending on the surrounding topography, the height of the wall, and the individual operator, the timber mats should not touch the stone wall on any side, and a sufficient air gap between the top of the stone wall and the timber matting directly above should be left to ensure the stone wall is not damaged during the passage of heavy machinery. Before and after photographs of the portion of the stone wall to be crossed should be taken and provided to Eversource Environmental Licensing and Permitting. • Elevating work pads near stone walls using timber matting - If work pads cannot be reduced in size to avoid stone walls, timber matting may be used to elevate the work pad, or portions thereof, above the stone wall to avoid impacts. None of the timber mats should be in contact with the stone wall and before and after photographs of the stone wall should be taken. If implementation of the four non-impact measures noted above is not feasible and either temporary or permanent alterations to a stone wall are necessary, Eversource Environmental Licensing and Permitting must be contacted prior to any alterations occurring to secure the appropriate permissions. These permissions may take several weeks to secure and may require input from the cultural resources consultant or Eversource Real Estate and/or Legal Departments. Prior to alteration, proper documentation of the wall should be obtained and provided to Eversource Environmental Licensing and Permitting. At a minimum, this effort should include recording the following: • Wall dimensions (total length, width, average height) • Any existing breaches • Wall location and general orientation on project maps Photographs (including a scale, if possible) should also be taken of the entire wall clearly showing all sides, with increased attention on any areas of the wall that will be modified (e.g., expanded breaches) or will need to be rebuilt. The removal of dense vegetation along the stone wall prior to photography is highly recommended. Once permissions to alter a stone wall and appropriate documentation ha ve been secured, the following BMPs should be followed during alteration and rebuilding: • While it is preferred that alterations be conducted by hand following traditional dry stone construction methods, construction machinery may be used when appropriate to the level of effort required and taking care not to unreasonably scratch or mar the stones or to begin excavating into soils underneath the wall. • Any removed stones should be stockpiled nearby, outside any identified sensitive environmental areas such as wetlands or rare species habitat. • When rebuilding, the wall should be reconstructed in the same location as the original and should match the original wall as closely as possible; if present, it is preferred that weathered/moss-covered surfaces are exposed. • When alterations/rebuilding is complete, additional photographs from all sides should be taken and provided to Eversource Environmental Licensing and Section 3 Construction Considerations Eversource Best Management Practices Manual 3-5 Permitting. 3.5.2 Unanticipated Discoveries During construction activities, most notably ground disturbing activities such as excavation, trenching, or grading, it is possible to discover previously unknown archaeological resources. Any specific procedures outlined in project-specific documents such as Post-Review Discoveries or Unanticipated Discoveries Plans should be followed. If such documents do not exist and a contractor encounters an unanticipated discovery, the contractor shall immediately notify the Eversource Construction Representative/Supervisor, secure the site, and not restart work in the area of the discovery until after the Eversource Senior Cultural Resources Program Administrator has granted clearance. 3.6 Human Remains In the event human remains are encountered, the contractor must immediately stop work and notify the Eversource Construction Representative/Supervisor, secure the site, and ensure that the remains are treated with the utmost dignity and respect. The remains should be covered and left undisturbed along with any associated artifacts. No photography of the remains is allowed and work will not resume in the area of the discovery until after the Eversource Senior Cultural Resources Program Administrator has granted clearance. In addition to these preliminary guidelines, all relevant state laws and guidelines, including, but not limited to, the Massachusetts Unmarked Burial Law (M.G.L. Chapter 38, Section 6) and the Connecticut Human Burials Law (Conn. Gen. State. Sec 10-388) must be adhered to. 3.7 Vernal Pools Construction within and across wetlands and in proximity to vernal pools should be limited to the extent practicable to avoid working in the periods between April 1 st and June 1st. This will allow for obligate vernal pool species to emigrate to the breeding areas, deposit egg masses, and allow for hatching and development of juveniles. Silt fence should be installed at the limits of the construction to prevent individual reptiles and amphibians from entering the workspace, but in a manner that does not impede movement to and from pools from adjacent forested uplands. Consider installing syncopated silt fencing. Protection Measures When performing construction activities in proximity to vernal pools, a number of protection measures should be implemented. Vegetation Removal • Maintain existing scrub-shrub vegetation (consistent with ROW vegetation management requirements) within 25 feet of vernal pools, except in areas where access roads and work pads must be installed. • Minimize removal of low growing (scrub-shrub) vegetation surrounding vernal pools by utilizing construction matting where access is needed. If vegetation must be cut adjacent to vernal pools, the cut vegetation (slash) should be left in place to serve as recruitment for leaf litter and coarse woody debris. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-6 Erosion and Sedimentation Control • Where the potential for sediment intrusion and runoff into a vernal pool exists, sedimentation and erosion controls shall be installed. • Promptly remove erosion and sedimentation control devices upon final revegetation and stabilization of the ROW. Access Roads • Use construction mats, corduroy roads, or clean materials (i.e., clean riprap, gravel, stone or equivalent and rock fords) in locations where existing on -ROW access roads must be improved and are adjacent to vernal pools. • Man-made depressions along existing on-ROW access roads provide low-quality vernal pool breeding habitat (due to an insufficient hydroperiod). Access roads must be graded and/or improved to accommodate project construction vehicles which may eliminate these depressions and the associated potential for amphibian breeding habitat. Perform improvements to on-ROW access roads outside of the breeding and migration seasons of vernal pool species to avoid direct impacts to amphibians that may breed in the man-made depressions along existing on-ROW access roads. Scheduling and Site-Specific Considerations • To the extent practicable (and in consideration of circuit outages and other construction timing constraints), schedule access road and work pad installation in and around vernal pool habitats to minimize interference with amphibian breeding and migration seasons. • For project activities that must occur adjacent to vernal pools during amphibian migration periods, implement measures on a site-specific basis to facilitate unencumbered amphibian access to and from vernal pools. Consider the site- specific conditions including the type of construction activity that will occur in proximity to a vernal pool, the amphibian species known to occur in the vernal pool, and seasonal conditions. Identify appropriate mitigation measures. Options to be evaluated to allow amphibian access to vernal pools may include, but not be limited to: syncopated silt fencing in the immediate vicinity of vernal pools; elevated construction matting; and aligning erosion and sedimentation controls to avoid bifurcating vernal pool habitat. 3.7.1 Certified Vernal Pools (MA) Encroachment upon Certified Vernal Pools (CVP) in Massachusetts should be avoided to the maximum extent practicable. CVPs are considered Outstanding Resource Waters (ORWs) in Massachusetts and are regulated under the 401 Water Quality Certification program. Consult with Eversource Environmental Licensing and Permitting. 3.8 Access Roads Existing construction access roads are unpaved roadways that work crews use to access a site within a ROW. These access roads were generally either permitted previously or Section 3 Construction Considerations Eversource Best Management Practices Manual 3-7 constructed prior to the promulgation of regulations and are previously authorized under past general permits. 3.8.1 New Access Roads New access roads are generally associated with new or large -scale projects that have separate permitting requirements. Construction of new access roads will be based on plans that are reviewed and approved by applicable federal, state, and local agencies. If a new access road is needed and not associated with a large project, notify Eversource Environmental Licensing and Permitting to make a decision on best access routes and identification of the necessary permits and approvals required to construct the new road. Permit requirements must be followed. 3.8.2 Existing Access Roads The travel surface width of access roads in upland areas is not to exceed 16 feet. This does not include side slopes. Maintenance of existing access roads includes mowing of vegetation, grading, placement/replacement of stone, and the installation/maintenance of erosion control features (e.g., water bars, swales, sedimentation basins). When access roads are in wetlands, measures should be taken to avoid disturbance to wetlands, waterways, and other sensitive environmental areas. If avoidance is not practicable, then measures should be taken to minimize the extent of disturbance. Alternate access routes should always be considered. Below is a list of methods that should be considered where disturbance is necessary: • Minimize the width of typical access roads through wetlands. If an existing access road is evident in the wetland based on the presence of previously imported road- building materials (e.g., crushed stone), the existing width of the access road must be maintained. If unable to ascertain the original width of the access, then do not make the road wider than 16 feet (including side slopes). • To the extent practicable, use low-impact vehicles and/or vehicles with low ground pressure when driving through wetlands. • Coordinate the timing of work to minimize impacts during the regulatory low-flow period under normal conditions, when water/ground is frozen, after the spring songbird nesting season, and outside of the anticipated amphibian migration window (mid- February to mid-June). The ACOE defines the low-flow periods for streams as follows: o Connecticut streams—July 1 through September 30 o Massachusetts non-tidal streams—July 1 through February 28 o Massachusetts tidal streams—November 16 to February 15 • Use construction mats in wetlands to minimize soil disturbance and rutting when work needs to occur during non-frozen ground conditions. • If practicable, conduct work manually if warranted (decision to be made by the Eversource Project Team). Existing access roads are characterized by a clear dominance of imported fill material to a depth of at least three inches. When determining the presence and extent of an existing access road, soil probes shall be advanced as necessary to establish the boundary between fill and native soil. In some cases, hydrophytic vegetation may have become established or ponding may occur within the limits of imported fill. In these cases, the clear and Section 3 Construction Considerations Eversource Best Management Practices Manual 3-8 consistent presence of fill along a distinguished route is considered a previously authorized fill. Where the existing access road is not evident, Eversource Environmental Licensing and Permitting must be consulted to make a determination whether stone can be placed in the wetland. If stone is not evident, through soil cores, hand digging or other methods, construction mats must be used. If permanent access is warranted through the wetland, the new access road will need to have a permitting review and will likely require permits. The access road in the wetland should not exceed 16 feet in width (unless there is evidence that the road was originally wider than 16 feet). Over time, existing access roads require maintenance and repair. Travel by construction equipment and general traffic to reach a particular porti on of the ROW must be via the designated access road and route. Changes in the location of the access road or the use of alternate roads must be reviewed and approved by the Eversource Project Team prior to their construction or use. Access road routes were selected to prevent degradation of the utility corridor, and must be constructed, used, and maintained in accordance with this BMP Manual, as well as federal, state, and local requirements, and other project plans. In some situations, it may be necessary to construct redundant access roads, this practice should be avoided to the extent practicable. Some appropriate reasons for suggesting alternate routes are: • Poor site conditions along preferred route because of weather or season. • Property rights constraints, or property owner’s preference. • Equipment requirements. • Unanticipated off-site access limitations along existing roads. Unanticipated access opportunities (e.g., ice, snow, other developments) which may avoid environmental disturbance and/or reduce cost. General Design: New and Existing Access Roads Construction access roads that require new grading and/or filling or are to be heavily used require the creation of a stable, load-bearing surface resistant to erosion. If the existing soil and subsoil are not well drained, it may be necessary to import an aggregate road base (i.e., gravel borrow) such as that meeting the requirements of aggregate found in the: • Commonwealth of Massachusetts Department of Public Works Standard Specifications for Highways and Bridges, Section 400 • Connecticut Standard Specifications for Roads, Bridges and Incidental Construction, Section M1.02 When the construction access road follows the same route as the permanent design road, establishing the grades and subgrade for the permanent roadway early in the construction sequence is recommended. The travel surface of construction access roads shall typically not exceed 16 feet in width except for passing points, where necessary. Subgrading shall not extend beyond the space required for the finished road and normal side slopes. Where practicable, construction access roads should conform to the contours of the land, Section 3 Construction Considerations Eversource Best Management Practices Manual 3-9 avoiding grades steeper than 10 percent and creating side slopes no steeper than a ratio of 2:1. If the side slopes are steeper than 2:1, then use of engineered slope stabilization methods may be necessary. Consider the volume and type of construction traffic as well as the extent that natural ground must be altered to accommodate the traffic. If no grading is required and traffic is sporadic (i.e., access roads used to maintain utility lines) the measures used may be limited to water bars, or some top dressing with gravel or stone in areas where the vegetation over soft soil is destroyed by traffic. During wet weather, these roadways can generate significant quantities of sediment if not constructed with adequate stormwater management and erosion control measures. During active construction or maintenance activities, inspection of the construction access road and associated erosion and sedimentation measures should be conducted by the person(s) designated at the pre-construction meeting, should occur regularly while the activity is occurring, and repairs to controls should be made in a timely matter. Repairs may include re-grading and/or top dressing the traveled surface with additional aggregate to eliminate ruts, as well as those repairs required by each erosion and sedimentation measure used. When the roadway is no longer needed on a regular basis, the access road should be reviewed to ensure that the road is left in a condition that prevents future erosion and sedimentation (e.g., installation of water bars, gravel). In some cases, permit conditions may require that the access road be removed and that the disturbed area be restored (e.g., seeded and mulched) in accordance with applicable permits as required to match the pre-construction conditions. Erosion and Sedimentation Controls Construction personnel are reminded to control erosion and flow conditions during access road construction or maintenance activities by utilizing the following erosion and sedimentation measures which are described and illustrated further in Appendix A: • Outlet protection, a level spreader, a trench breaker, a sediment trap or basin, or a stone check dam may be used to de-energize concentrated flows from diversions and in temporary channels. • Geotextile silt fencing, compost filter berms, straw wattles and straw bale barriers may be utilized to provide protection at the toe of fill slopes and discharges from water bars. • Side slopes can be protected by installing erosion control blankets and seeding the area with a fast-growing native or annual grass mix. • Dust control should be employed when construction access road conditions create airborne dust. • Geotextile fabric shall be used beneath all new fill and construction entrances, where needed. **The use of hay and/or hay products is strictly prohibited.** **The use of nylon and/or plastic netting is strictly prohibited.** 3.8.3 Best Management Practices – New Access Roads The following are BMPs that are applicable to new access roads in uplands and are described at the following tabs: Construction Entrance Track Pad (see Figure A01 in Appendix A) Section 3 Construction Considerations Eversource Best Management Practices Manual 3-10 Stormwater Management BMPs (includes Water Bars [Figure A02], Drainage Swales [Figure A03], and Sedimentation Basins [Figures A38-A41] in Appendix A) Construction Entrance Track Pad Applications: Erosion and sedimentation control, roadway protection Limitations: • Maintenance is required if the pad becomes clogged with soil. • Muddy conditions may warrant the use of a tire wash station. Overview: Where access roads or construction areas connect to paved roads, a stone track pad must be installed at the construction entrance to prevent construction machinery from tracking soil onto paved roadways. Materials appropriate to construction site soil conditions should be employed and/or replenished, as necessary. Installation: • Use 3- to 6-inch washed stone to install stone tracking pad s at a minimum length of 50 feet and a minimum depth of 12 inches. • On sites with clayey soils, underlay stone tracking pads with a geotextile liner to prevent the stone from sinking into the soil. Maintenance: • Periodically inspect the stone in the entrance track pad. If the pad becomes clogged with soil, remove and refresh and/or clean stone. Additional Comments: If muddy conditions warrant the use of a tire wash station, procedures should be established to ensure soils are not tracked off site. Where appropriate and when safety and environmental conditions are considered, vehicle tires or tracks may be spun quickly (“burn out”) on the track pad to further facilitate the removal of soil. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-11 Water Bar Applications: Erosion and sedimentation control Limitations: • Should never be used to direct a watercourse into another waterbody or to divert unfiltered runoff to a wetland. • Can impede vehicular movement. • Damage from vehicle traffic and stormwater flow may require water bars to be reinstalled/reworked at the beginning and end of each construction season. Overview: Water bars are linear features built diagonally across access roads or ROWs to redirect stormwater runoff away from the road surface at non-erosive intervals. In general, they consist of a trench dug at least 6 inches below grade followed by an earthen mound at least 6 inches above grade. Use water bars to prevent erosion on sloping roadways less than 100 feet wide. Water bars must be designed to be stable througho ut their useful life and meet the criteria in the table below. The maximum capacity should be the peak runoff from a 10-year storm. Installation: • Set water bar direction to utilize stable outlets and do not allow upslope water bar runoff to converge with down slope water bars. Water bars should be directed into well vegetated upland areas, sediment basins, or other erosion and sedimentation controls (e.g., straw bales, silt fence) as needed. • Construct the bar immediately after vegetation has been clear ed on constant or slightly increasing grades, not exceeding 2%. Avoid reverse grades. • Mark the location and width of the ridge and disk the entire length. • Fill ridge to above the design height and compact with wheeled equipment to the design cross section. • Construct sediment traps or outlet stabilization measures, as needed. • After the area has been permanently stabilized, remove the ridge and channel to blend with the natural ground level. • Seed and mulch diversions that are intended for use for more than 30 days. Minimum Cross Section Top Width (ft) Height (ft) Side Slopes 0 1.5 4:1 4 1.5 2:1 Section 3 Construction Considerations Eversource Best Management Practices Manual 3-12 Maximum Recommended Spacing1 Land Slope (%) Diversion Spacing (ft) < 5 125 5 to 10 100 10 to 20 75 20 to 30 50 > 35 25 1 Recommendations for ROW widths less than 100 feet as per the Massachusetts Erosion and Sediment Control Guidelines for Urban and Suburban Areas (MassDEP, March 1997). Maintenance: • Inspect each week and after rain events of 0.25 inches (MA) or 0.50 inches (CT) or greater, or more frequently per permit conditions or Eversource Environmental Licensing and Permitting. Repair damage caused by construction traffic or erosion. • Remove accumulated sediment and debris from the trench and stabilize outlets. • If necessary, repair ridge to a positive grade and cross section, and add gravel at crossing areas. • Use routine inspections to determine if the original spacing is adequate or if additional water bars need to be constructed. Drainage Swales Applications: Convey stormwater away from work area and/or improve water quality and reduce peak runoff. Limitations: • Vegetated swales need to have adequately established vegetation before flow is diverted to them. • Need to have adequate bottom stabilization to prevent scouring. Overview: Drainage swales usually consist of a ditch that is either vegetated or lined with riprap, erosion control blankets, or other materials. They are natural or constructed waterways/outlets that intercept, redirect, and convey storm water away from the work area to a stable location and are used in areas where concentrated runoff would otherwise cause erosion/flooding. Swales can be used to reduce erosion in uplands and/or prior to discharge of stormwater flows to natural receiving wa ters (e.g., wetlands or streams). They also help to reduce surface flow velocity and turbidity. Grass Lined Channels (Stabilized with vegetation) • Use where vegetative lining will provide sufficient stability, slopes are less than 5%, and space is available for a wide cross section. Installation: • Remove trees, brush, and stumps. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-13 • Excavate and shape channel to dimensions on plans. Overcut 0.2 ft for vegetative growth. • Install temporary liner or riprap at inflows and stabilize outlets. • Vegetate immediately after construction and divert water until grass establishes. Install matting if flow cannot be diverted. • Install sod rather than seeding where slopes approach 5%. • Spread topsoil to a minimum of 4 inches where soil conditions are unfavorable. Seeded channels should be mulched. Vegetated Swales (Stabilized with dense vegetation) • Use for water quality improvement and peak runoff reduction. Applicable for small drainage areas with relatively small amount of impervious cover. The grassed waterway is used to convey runoff at a non-erosive velocity. Dense vegetation can be established and a stable outlet constructed. Installation: • General design parameters are as follows: minimum capacity 10-year, 24-hour storm; design slopes to prevent erosion during the 2-year storm event; maximum side slopes 3:1; bottom width 2 to 8 feet. • Vegetate with a native erosion control seed mix for use at moist sites and divert flow until established. Riprap Lined Channels (Contains lining of riprap or stone) • Use on sites where channel flow velocities exceed those acceptable for grass lined swales. Applicable where vegetative establishment is not possible or there are steep grades, wetness, highly erodible soils, seepage or prolonged base flow. Installation: • Remove trees, brush, and vegetation from channel area. • Stabilize inlets and install outlet protection. • Construct channel and install filter and lining as shown on plan. • Use the maximum stone size for riprap plus thickness of filter. Maintenance: • Swales need to be routinely maintained to prevent brush/sediment buildup. Inspect swale regularly and after every rain event (0.25 inches (MA) or 0.50 inches (CT), or greater). Repair and/or re-seed rill or gully erosion. Remove accumulated sediments and brush before it reaches a depth of 6 inches. Additional Comments: • Depth and spacing of swales should be dependent on runoff conditions of the specific site. • If required, install check dams constructed of riprap or other materials to slow flows along certain reaches of a swale. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-14 • Remove temporary swales once construction is complete or areas are stabilized. If leaving swales in place will provide long -term benefits and be compatible with the ultimate use of the site, then they may remain in place. Sedimentation Basins Applications: Erosion and sedimentation control Limitations: • Traps and basins need to be adequately sized based on expected rain events and the contributing drainage area. Overview: Sediment traps and basins are used to filter and settle out suspended solids in stormwater runoff before water is released into a wetland or other unprotected and/or sensitive environmental area. A sediment trap is a temporary measure installed during construction to detain runoff, while a basin is a more permanent measure. Basins are also used where other erosion control measures are not adequate to prevent off-site sedimentation. Sediment traps and basins should have three components: a forebay, a check dam, and a basin. Debris and some sediments begin to settle out of the water in the forebay. The stone or straw bale check dam filters more suspended solids as water flows through. The actual basin is a low-velocity pool where suspended solids settle out of the water column before the water is released at the outlet. Based on the size of the project area, a qualified engineer may be required to calculate the appropriate size of the basin. State-specific guidance for basin sizing can be found in the following locations: • Massachusetts Erosion and Sediment Control Guidelines for Urban and Suburban Areas (Page 140); http://www.mass.gov/eea/docs/dep/water/esfull.pdf • 2002 Connecticut Guidelines for Soil Erosi on and Sediment Control (Section 5-11- 1); http://www.ct.gov/dep/cwp/view.asp?A=2720&Q=325660 . Installation: Drainage area of 5 acres or less: • Install to direct stormwater runoff to the sedimentation trap or basin. Form basin by excavating a depression similar to a small pond or by placing an earthen embankment across an existing drainage swale or naturally low area. • The ratio between the basin length and width should be greater than 3:1 (L:W). A ratio of 9:1 is recommended. • Clear, grub, and strip all vegetation and root material from area of embankment and place embankment fill in lifts (<9”/lift, max). Compact fill and construct side slopes 2:1 or flatter. Excavate rectangular outlet section from compacted embankment. • Filter fabric may be installed on bottom and sides of basin and covered by riprap. • Extend outlet apron/spillway below toe of dam on level grade until stable conditions are reached (5 feet minimum). Cover inside face of s tone outlet section with a 1- Section 3 Construction Considerations Eversource Best Management Practices Manual 3-15 foot layer of ½- to ¼-inch washed stone. • Use permanent or temporary seeding to vegetate embankments, spillways, and disturbed areas downgradient of the basin. Drainage area of 10 acres or less: • Locate the basin in an easily accessible upland area, not a wetland area. • Install the basin so that it intercepts the largest possible amount of runoff from the disturbed area. • Divert sediment-laden water to the upper end of the sediment pool to improve trapping effectiveness. • Basin should have a minimum volume based on ½-inch of storage for each acre of drainage area. • Size basin to provide a minimum detention of 12 to 24 hours at the maximum runoff quantity expected for the duration of the basin’s use. Maintenance: • Monitor the amount of sedimentation in the trap/basin. Install a stake with a marking at half the design depth. Remove sediment when it reaches this mark. • Inspect after every rain event. • Clean or replace the spillway gravel and re-seed/plant vegetation, as needed. • Monitor embankment, spillway, and outlet for erosion. Repair erosion problems immediately. Additional Comments: Construction of sediment traps and/or basins should occur before primary construction on a project begins. They are often a critical stormwater management component for larger construction sites and/or those with poorly drained upland soils. If compatible with the post-construction site use, it may be appropriate to leave sediment basins in place indefinitely. 3.8.4 Construction in Wetlands Access roads that are constructed in or across wetlands require the following considerations in addition to the considerations for access roads in uplands: • Construction of new access roads in wetlands, whether temporary or permanent, that do not utilize construction mats (e.g., earthen and/or rock fill roads, corduroy roads) requires considerable project specific permitting and design. These types of projects should comply with project specific permits and plans, while only using this BMP manual as a general reference source. Permits often also require wetlands replication when permanent new access roads are constructed in wetlands. • Avoid putting the construction access road in a wetland whenever practicable. Explore all feasible and prudent alternatives before determining that a wetland crossing is necessary. When avoidance is not practicable, consider crossings that will result in the least amount of disturbance. This may involve locating the construction access road so that it crosses the wetland at its narrowest width or uses areas previously disturbed for access or other purposes. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-16 • Minimize the width of the temporary construction access road through the wetlands (generally no wider than 16 feet when using construction mats). It is preferable to have a passing point created before and after the wetland crossing, but internal passing points may be needed if the crossing is long or critical sight line restrictions exist. • Construct access roads so that wildlife is able to pass under or go through the road. In areas where the road is only one construction mat thick, allow for passageways or “gaps” between construction mats. In locations where the access road is greater than one mat thick, install elevated construction mat road crossings or ”bridges .” Gaps and/or bridges are to be placed along the access road at intervals no less than 50 feet. • Consider the soil conditions. Expect deep organic wetland soils to require geotextiles, construction mats, or other materials during use to keep imported road materials separated from wetland soils. In shallow organic or saturated soils, thick plywood sheets or AlturnaMATS® may be sufficient to support a stable travel surface for small, lightweight vehicles. In addition, in areas which are inundated or have deep organic wetland soils, it may be necessary to use more than one layer of construction mats. • Prevent obstructions to surface and subsurface flow across and through the construction access road. Provide adequate drainage. This may require the use of crushed stone, a layer of log corduroy, construction mat bridges, or multiple cross culverts, particularly if the wetland does not contain a well -defined watercourse channel and/or the wetland crossing is long. If the wetland soils are susceptible to seasonal high groundwater tables or flooding, then give additional consideration for maintaining flows across and/or over the construction access road without causing erosion or siltation during such times. • Plan in advance how the construction access road will be removed and the wetland restored. A road stabilization geotextile can facilitate the segregation of imported soils and crushed stone and/or log corduroy from the native wetland soils and make wetland restoration easier. However, after the end of an extensive project and a highly traveled crossing, stone removal from the wetland surface will still usually have to occur, even when placed in conjunction with geotextile. In some cases, access roads may not need to be constructed in a wetland to gain acce ss into or through a wetland if the work can be designed such that disturbances to the wetland are avoided or negligible. Options to be considered are presented below. Equipment Selection and Usage: • Low ground pressure equipment - Using equipment that reduces the pressure it exerts on the ground can minimize disturbance to sensitive areas. Employing the use of equipment with wide tires, rubberized tracks, and low ground pressure (<3 psi when loaded) can help minimize soil compaction. • Wide tires - Increasing the width of tires will increase traveling surface area and therefore reduce the amount of ground compaction that the equipment will cause. Ultimately, this will reduce rutting, and allow for easier maneuvering of the vehicle. However, wide tires may be costly and will require a wider travel area. • Rubberized tracks - Equipment with rubberized tracks spreads the weight of the vehicle over a much larger surface, reducing ground pressure and enabling the vehicle to move more freely through wet substrates. Each track can be between Section 3 Construction Considerations Eversource Best Management Practices Manual 3-17 1.5 and 3 feet wide, length depending on the width of the vehicle. This can greatly reduce rutting and allow the vehicle to move with less difficulty through wet substrates. • Lightweight equipment - Disturbance in a wetland area can be lessened by reducing the size of equipment (e.g., ORVs, Gator™) used in sensitive environmental areas. This reduces the amount of pressure to the travel surface as well as the necessary width of access ways. Timing of Work: • Work during frozen conditions. Activities conducted once wetland areas are frozen can minimize rutting and other disturbance to the surrounding environment. Work during this time also generally reduces disturbance of aquatic and terrestrial wildlife movement by avoiding sensitive breeding and nesting seasons. • Work during the “low flow” period. Conducting work during the low flow period can reduce disturbance to surface water and generally avoids spawning and breeding seasons of aquatic organisms. The ACOE defines the low-flow periods for streams as follows: o Connecticut streams—July 1 through September 30 o Massachusetts non-tidal streams— July 1 through September 30 o Massachusetts tidal streams—November 16 through February 15 Alternate Access: • Manual access – Consider accessing work areas on foot through terrestrial areas and/or by boat through open water or ponded areas. Smaller projects (e.g., repairs to individual structures or parts of structures) do not categorically require the use of heavy machinery and should be accessed manually to the extent practicable. • Limit trips – Multiple trips through a wetland have shown to increase the potential for damage and requirement for matting. Try to limit trip to one in and one out. Use of overhead/aerial access (e.g., helicopters): • Using overhead or aerial equipment can be expensive a nd is not always feasible, but it may be appropriate in some situations to get vehicles and other equipment to a site that may be otherwise very difficult to access. The use of overhead and/or aerial equipment may be beneficial for work in areas where larg e water bodies, deep crevices, or mountainous areas hinder ground access. Erosion and Sedimentation Controls: Construction personnel are reminded to control erosion and flow conditions during new access road construction by utilizing the following erosion and sedimentation measures which are described and illustrated further in Appendix A: • Straw wattles [Figure A26 in Appendix A], geotextile silt fencing [Figure A22 in Appendix A], and straw bale barriers [Figure A21 in Appendix A] may be installed at the edges of earthen roads or construction mat roads to prevent erosion of soil into wetlands from the road fill or tracked soil on construction mats. • In areas where silt fencing is required for more than one activity season, syncopated silt fencing [Figure A23 in Appendix A] may be installed to permit animal crossings. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-18 • Side slopes of earthen roads can be protected by installing erosion control blankets [Figure A25 in Appendix A] and seeding [Figure A32 in Appendix A] the area with a fast-growing native or annual grass mix. • Dust control should be employed as necessary when construction access road conditions create airborne dust when necessary. Refer to Section 3.16 of this BMP Manual. Best Management Practices – Construction in Wetlands The following are BMPs that are applicable to new access roads in wetlands and are described at the following tab: Construction Mats (includes Elevated Construction Mats and AlturnaMATs®; see Figures A04 – A06 in Appendix A) Permeable Road (see Figure A08 in Appendix A) Dewatering (see Figures A39 – A41 in Appendix A) Construction Mats (i.e., timber or swamp mats) Applications: Wetland crossings, rut minimization • Used for access where the ground surface is unstable due to shallow, standing water, saturated soils, or other substrates not suitable for heavy vehicles. Limitations: • Only for temporary use. Generally, mats should be removed upon construction completion. • May float away in high water conditions. • Need to be installed with heavy machinery. • AlturnaMATs® limited to smaller vehicles and equipment. • Equipment operators should remain cautious so as not to drive off or slip off the side of the mats. • In winter, mats must be plowed and sanded or heated to prevent equipment fro m sliding off mats. Use of a deicing agent requires approval by Eversource Environmental Licensing and Permitting. Snow removal must be conducted in accordance with the Eversource Snow Removal BMP (refer to Section 3.15). Installation: • Place mats along the travel area without any gaps and so that each board is positioned perpendicular to the direction of traffic. Position mats so that they are offset far enough from the resource area so that ruts are not created when equipment enters and exits a sensitive area. • Remove mats by “backing” out of the site and removing mats one at a time. Regrade soils to pre-existing contours while taking care not to compact soils. • Clean mats after use to remove any invasive plant species seed stock. Cleaning methods may include, but are not limited to, shaking or dropping mats in a controlled manner with a piece of machinery to knock off attached soil and debris, Section 3 Construction Considerations Eversource Best Management Practices Manual 3-19 spraying with water or air, sweeping, or exposing the mats to high temperatures. • Clean mats that were used in wetlands dominated by invasive species using brooms, shovels, and compressed air, if needed. Additional Comments: Construction mats installed in wetlands categorized as ORW s in Massachusetts must be underlain by non-woven geotextile, which can be placed directly on the ground surface beneath the first layer of matting or atop the first layer of matting if additional layers of mats are to be installed. Lightweight, easy to maneuver alternatives to traditional mats are available. For example, AlturnaMATS® are half-inch thick polyethylene slip-resistant ground protection mats available in dimensions up to 4 feet by 8 feet and weigh between 21.5 and 86 pounds. Mat anchoring may be required for matting installed in areas prone to flooding, such as stream crossings, shorelines of lakes and ponds, floodplains where known base flood elevations are 2 feet or greater above the ground surface, and tidal areas, and when mats will be in place in these areas for more than two weeks during hurricane season. The need for, and type of, anchoring should be coordinated with Eversource Environmental Licensing and Permitting. Examples of mat anchoring include: • Linear ropes anchored using helical screws, manta ray anchors, or posts. • Cable or report in chain pockets and run linearly. Construction mat anchoring methods are illustrated in Figure A07 in Appendix A of this BMP Manual. Additional methods may be necessary depending on site and/or weather conditions. Permeable Road (i.e., rock sandwich, French Mattress, or road with continuous cross- drainage) Applications: Temporary wetland crossings, rut minimization Limitations: • Must be removed entirely at the end of construction unless project -specific permits have been obtained to allow for permanent wetland fill. • Not appropriate for areas where concentrated, high volume and/or velocity water flow will intersect the road (i.e., stream crossings). • Need to be installed with heavy machinery. • Equipment operators should remain cautious so as not to drive or slip off the side of the road. Overview: Permeable roads are used for access in situations not suitable for heavy vehicle use often due to unstable ground surfaces with shallow standing water, saturated soils, or other unstable substrate. Installation of a permeable road can also help reduce the potential for frost action and pothole creation by preventing groundwater from wicking up into the road fill material. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-20 Installation: • Cover existing soil with a geotextile fabric prior to road construction. Excavation of existing soil is generally not recommended in order to minimize impacts to the resource area. Construct road on top of the soil surface, as shown on the typical on the next page. Drainage layer materials include 3- to 6-inch rock (12-inch minimum depth) or log corduroy (2-inch minimum diameter). • Install the road so that it is offset far enough from the resource area so that ruts are not created when equipment enters and exits a sensitive area. • Remove road by “backing” out of the site and removing road one section at a time. Regrade soils to pre-existing contours while taking care not to compact soils. Maintenance: • Regularly inspect and clean edges of cross-drainage layer along the sides of the road to prevent clogging by debris, leaf litter, sediment, etc. 3.8.5 Watercourse Crossings There are a number of BMPs that can be used to minimize disturbance to streams. For each application, consider the site and project needs to select a method that is cost effective and will incur the fewest secondary disturbances. Additional erosion and sedimentation controls (e.g., straw bales) may be required in conjunction with the stream crossing BMPs to protect sensitive areas. The stream crossing methodology chosen will depend largely on the equipment required for a particular task, the existing environmental conditions, and the duration of the crossing. In constructing any stream crossing, care should be taken to limit disturbance to the extent practicable within 100 to 200 feet of the stream banks (the riparian area). The riparian area provides habitat to a number of speci es and provides protection and shading to the stream. Erosion and Sedimentation Controls Construction personnel are reminded to control erosion and flow conditions during new watercourse crossings by utilizing the following erosion and sedimentation measur es which are described and illustrated further in Appendix A: • Straw wattles [see Figure A26 in Appendix A], geotextile silt fencing [see Figure A22 in Appendix A] and/or straw bale barriers [see Figure A21 in Appendix A] may be installed at the edges of earthen roads or construction mat roads to prevent erosion of soil into watercourses from the road fill or tracked soil on construction mats. These controls however should generally not be placed within a watercourse. • Side slopes of earthen roads can be protected by installing erosion control blankets [see Figure A25 in Appendix A] and seeding [see Figure A32 in Appendix A] the area with a fast-growing native or annual grass mix. Best Management Practices – Watercourse Crossings The following are BMPs that are applicable to new access roads watercourse crossings and are described at the following tabs: Stream Crossings without Bridges (includes limiting turbidity and stone crossing ; see Figures A05, A06, and A12 in Appendix A) Section 3 Construction Considerations Eversource Best Management Practices Manual 3-21 Bridged Crossings (includes construction mat bridges and rail car frame bridges; see Appendix A) Dewatering (see Figures A39 – A41 in Appendix A) Stream Crossings Without Bridges: Limiting Turbidity Applications: Stream crossing, turbidity control Limitations: • Limited to areas where stream banks and bottoms will not be significantly damaged by the crossing. Overview/Use: • In some situations, such as routine or emergency maintenance with small ORVs, pickup trucks or tracked equipment, it may be acceptable for equipment to simply travel (perpendicularly) through a stream. • Crossings are generally considered acceptable in situations where there is an existing or historic access road, a stable rock or sand/gravel stream bottom, and/or the crossing is at a relatively narrow reach of the stream and any adjacent wetlands. • Cross streams slowly to minimize in-stream turbidity. Stream Crossings Without Bridges: Stone Crossings Applications: Stream crossing, turbidity control Limitations: • Only use in small (less than 2 feet wide or braided) intermittent streams which do not appear on USGS topographic maps and have a downstream section with a gradient greater than 20%. • Not suitable in areas where there could be a potential for fish passage. • Stone size should be sufficient to allow for macroinvertebrate passage. • Not preferred for new access road crossings; generally more suitable for existing access road crossings. • Project-specific permitting may be required to allow for installation of stone within a stream bed. Consult with Eversource Environmental Licensing and Permitting prior to using this crossing method. Overview/Use: • Use to cross small streams with stable stream bottoms. • Carefully place 6-inch to 8-inch clean angular stone within stream at crossing. Limit width of stone to that needed for widest vehicle/equipment to crossing the stream. • Drive over stone slowly. • Leave riprap in intermittent streams for future use. More damage will occur by removing stone. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-22 Bridged Crossings: Construction Mats as Temporary Bridge Applications: Watercourse crossings Limitations: • Installation requires machinery. • May become unstable under high flows. Overview/Use: • Untreated wooden construction mats may be used as a temporary bridge over a stream to allow construction vehicles access to the work site. Construction mat bridging is suitable for crossing intermittent and perennial streams. Before constructing a stream crossing, confirm that the construction mats are capable of supporting the equipment to be used. • Place small sections of matting on either side of the stream parallel to the flow of water at top of banks to act as supports. Then place mats perpendicular to the stream and resting on top of the initial construction mat supports. • Install non-woven geotextile between the first and second layers of matting; install erosion control barriers (e.g., straw bales, straw wattles, silt socks) along edges of timber matting to minimize potential for soil to discharge to the stream. • Use of non-woven geotextile fabric at ORW crossings (MA) is required. Bridged Crossings: Rail Car Frame as Temporary Bridge Applications: Watercourse crossings Limitations: • Requires heavy equipment for transport and installation. • Expensive. • Banks must be stable to support heavy loads. Overview/Use: • Used rail car frames can be used for crossing larger and deeply incised streams where construction mats are unsuitable. • Place the rail car frame perpendicular to the stream flow and between opposing banks. Use timber frame footings, if necessary. Next, place construction matting • Install non-woven geotextile between the first and second layers of matting; install erosion control barriers (e.g., straw bales, straw wattles, silt socks) along edges of timber matting to minimize potential for soil to discharge to the stream. Use of non-woven geotextile fabric at ORW crossings (MA) is required. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-23 Culvert Installation/Repair/Replacement *Contact Eversource Environmental Licensing and Permitting prior to performing any culvert installations, repairs and/or replacements* Applications: Stream and wetland crossings Limitations: • Permitting and design are required for new culvert installation or expansion of existing culverts over streams and wetlands. Significant regulatory requirements must be followed. Permitting restrictions on time of year use. • Installation may require in-stream work; dewatering and sedimentation concerns. • Culverts are susceptible to washouts, sedimentation, erosion, and failure during heavy wet-weather events and flooding. • Culverts require routine and long-term maintenance because they often become clogged with debris or other obstructions. Overview: Culverts are installed to maintain wetlands or streams at road crossings. Hydraulic calculations are required at all crossings to determine the area that will drain to the culvert. General Design Guidelines: • Size culverts to handle the maximum expected flow of the wetland or watercourse. It is preferable to have one large culvert rather than multiple culverts. Corrugated culverts are favored because they slow the water velocity. HDPE corrugated pipes are preferred to metal. • Design culverts to withstand and accommodate high flows while maintaining existing low flows and not impeding on the movement of indigenous aquatic life. Culverts must be sized to accommodate flows from at least the 100-year storm and preferably 500-year storm. • The maximum velocity at the culvert outlet should be consistent with the velocity of the natural channel. To mitigate higher velocities, use outlet protection measures, energy dissipation, and channel stabilization, if necessary. • Refer to state specific stream crossing guidance documents for additional design requirements: o Connecticut: Stream Crossing Guidelines, CT DEEP, Inland Fisheries Division Habitat Conservation and Enhancement Program, February 26, 2008 (www.ct.gov/deep/lib/deep/fishing/restoration/streamcrossingguidelines.pdf) o Massachusetts: Massachusetts River and Stream Crossing Standards, River and Stream Continuity Partnership, March 1, 2006, Revised March 1, 2011 (https://www.nae.usace.army.mil/Portals/74/docs/regulatory/StreamRiverCo ntinuity/MA_RiverStreamCrossingStandards.pdf) Installation: • Construction mats may be placed over culverts to provide structural protection from heavy loads. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-24 • Backfill culverts with natural substrate matching the upstream and downstream streambed substrate, even when fish passage is not a concern. Other aquatic organisms rely on natural streambed sediment to aid their movement. • Strive to install culverts with minimal disruption to the watercourse and riparian buffer zone. • Culvert length should be as short in length as practicable. Cut culverts to size if they are protruding into the natural streambed. Maintenance: • Remove debris and sediment from culverts to maintain an open channel for flow. A clogged culvert could result in flooding and washout. Pole Fords Applications: Stream Crossings Limitations: • Limited to streams with gently sloping adjacent land. Overview/Use: • Poled fords are used in remote locations where a stream crossing requires a functional BMP, but it is impractical to bring in larger materials. Sufficiently sized wood poles or saw logs of may be laid in the streambed parallel to the flow. • Gently slope the road to and from the streambed at a maximum ratio of 1:5 (V:H). To limit disturbance to the riparian area, install engineering fabric and cover with an aggregate bed at the approach and exit. • Use poles with a minimum length of ten feet. • Remove poles immediately after use. 3.9 Slope Excavation Engineering designs may be required for any changes in upland areas that could potentially direct or channel water across the face of slopes, particularly terrace escarpments or other highly erodible soils. No snow or soil piles, construction materials, or equipment should be stored in the immediate vicinity at the top of the terrace escarpment or other highly erodible soils. 3.10 Vegetation Removal and Preservation Care should be taken to limit disturbance to the extent practicable when removing vegetation. Grubbing is not preferred as it results in considerable ground disturbance that could result in erosion and should be avoided to the extent feasible. Utilize grubbing only when all other methods cannot be used to prepare stable and safe work areas. If grubbing is necessary, the area must be seeded and mulched to protect it prior to the end of the workday. During mowing and trimming, woody debris greater than two (2) inches in diameter should not be placed in wetlands, and no woody debris should be placed in standing water. Permit conditions may mandate all woody debris to be removed from sensitive environmental areas. Mowing must be kept to a minimum, particularly at road crossings. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-25 3.10.1 ROW Vegetation and Eastern Box Turtle (EBT) – MA only Eastern box turtles (EBT) are often found near small streams and ponds and inhabit old fields, deciduous forests, and logged woodlands. Adults are completely terrestrial, while the young may be semiaquatic. EBTs hibernate on land by digging down in the soil between October and April. They have an extremely small home range and can usually be found in the same area year after year. EBT populations have been negatively impacted by the loss of suitable habitat. Some turtles may be killed directly by construction activities, but many more are lost when important habitat areas for shelter, feeding, hibernation, or nesting are destroyed. As remaining habitat is fragmented into smaller pieces, turtle populations can become small and isolated. Turtles are long-lived and the loss of even a single adult turtle can negatively impact the persistence of a local population. Therefore, vegetation removal in ROWs should be performed in a manner that minimizes impacts to turtle populations. Cleared and Maintained ROW—EBTs have been found to use existing ROWs for foraging and nesting. Whenever feasible, perform maintenance mowing in identified habitat during inactive periods (November 1st to March 31st). Turtle BMPs are not required for work performed during the inactive period. If mowing during the active turtle season (April 1 st to October 31st) is required, turtle sweeps should be conducted by trained personnel prior to mowing activities; mow vegetation to no lower than seven (7) inches. Use Brontosaurus or Fec on mower heads to minimize the impact to identified habitat areas. Do not used Flail -type mowers during the active season. Additionally: • Avoid direct harm to turtles. Visual inspections (“turtle sweeps”) of the work area must be conducted by trained personnel prior to the commencement of work. If turtles are encountered, they should be removed from the work area and reported to NHESP. Use extra care when using heavy machinery or traveling in vehicles through areas mapped as turtle habitat. Any silt fencing used in these areas should be removed as soon as site stabilization has occurred; fencing can be a barrier to turtle movements . Alternatively, install silt fencing in accordance with the Syncopated Silt Fence detail (see Appendix A). If required, excavation should be completed within one (1) day and/or open excavations should be backfilled daily to prevent turtles from becoming trapped. Uncleared ROW—When project work requires vegetation removal in an uncleared ROW, cut and mow uncleared portions of EBT habitat during the active season (April 1st to November 1st). If clearing must be conducted during hibernation periods, pre-planning will involve conducting a turtle survey and the possible use of telemetry. Consult Eversource Environmental Licensing and Permitting before performing work because this activity may not be covered under the OMP and may require a permit. 3.10.2 ROW Vegetation and Other Protected Turtles In addition to EBTs, some ROWs overlap with known habitat of other protected species of turtles. In Massachusetts, these species include Blanding’s Turtle, Bog Turtle and Northern Red-bellied Cooter. If any work, including but not limited to vegetation Section 3 Construction Considerations Eversource Best Management Practices Manual 3-26 management, is scheduled to occur in the habitats of these turtles at any time of the year, avoid wetland work. If unavoidable, operation and maintenance work in wetlands should be minimized to the greatest extent practicable. If work must occur in wetlands, the following guidelines apply: • Any work should be reported to NHESP • Work within wetlands mapped as habitat for the Bog Turtle or Northern Red - bellied Cooter must be reviewed on an individual basis by NHESP. Recommended Maintenance Activity if the Existing ROW is: Time Period Turtle Status Cleared and Maintained Uncleared April 1 to November 1 Active Perform only if required— Mow vegetation no lower than seven (7) inches and use recommended mower heads Recommended—Cut and mow uncleared areas November 1 to April 1 Inactive Recommended—Perform maintenance mowing Not recommended— Requires turtle survey at minimum before removing vegetation General Construction Recommendations –The following are general construction guidelines for protecting turtles: • Install silt fencing around the work area prior to construction activity. Consider using syncopated silt fencing (see Figure A23 in Appendix A). • Turtle training is required for all contractors. Apprise workers of the possible presence of turtles and provided a description of the species. Include a turtle sweep reminder on the Daily Tailboard. • Conduct a turtle sweep after installing silt fencing and before conducting work. • Perform daily turtle sweeps in work areas before performing any work. • Carefully move any turtles that are discovered to an area immediately outside of the fenced area. Position turtle in the same direction that it was walking. • Perform work with caution during early morning and evening hours. Take special care not to harm basking or foraging individuals. • Remove silt fencing after work is completed and soils are stable so that reptile and amphibian movement between uplands and wetlands is not restricted. • Return temporary cross-country access routes to pre-construction grade, seed if adequate root and seed stock are absent, and mulch. Do not seed pre -existing sandy soils that are within mapped rare turtle habitats unless directed by Eversource Environmental Licensing and Permitting in order to avoid alte ring nesting habitat. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-27 3.10.3 Preservation of Existing Vegetation Preserve the existing vegetation (i.e., groundcovers, vines, shrubs, trees) when practicable to improve soil stability and decrease the runoff volume and velocity. Identify and protect specified trees for erosion and sediment control benefits and /or aesthetic purposes. Consider saving trees that provide shading or screening benefits, particularly in residential areas. Preserve existing vegetation by reducing the width of a cleared ROW at stream crossings. 3.10.4 Invasive Plant Species Invasive plant species are non-native species that invade natural communities and develop self-sustaining populations. The start of many infestations is often tied to a disturbance, and once established, the invasive species spread into undisturbed landscapes. They out-compete native species, disrupting ecological p rocesses, and cause a loss of economic value or output. It is illegal to transport, to introduce, and/or propagate state-listed invasive species. Cleaning, draining and drying equipment between sites is mandated for aquatic invasives, and recommended for t errestrial equipment. Power washing of equipment and gear between sites is recommended, where feasible. At a minimum, visual inspection and hand removal of any plants, seeds, propagules, insects, mud, etc. is encouraged to maintain compliance with state la ws and rules. The linear nature of utility maintenance activities in vegetated corridors entails that a range of vegetative communities may be encountered by equipment, vehicles and personnel during the course of a single maintenance project or when mobilizing from one project site to another. It is especially important to follow best management practices when mobilizing equipment, vehicles and personnel from an area infested with invasive species to an un-infested area. 3.10.4.1 Project Planning – Invasive Plant Species Prior to starting utility maintenance work, the project area should be evaluated to determine: • Do invasive plant species exist in the project area? • Do project activities have the potential to contact invasive plants or disturb soils in a manner that could potentially spread live plant parts or viable seeds? • If invasive species are not present, or if it is not possible or not feasible to identify invasive plant species within the project area, follow best management practices to minimize the disturbance and spread of soil and/or plant matter. 3.10.4.2 Species Identification It is imperative that workers who will be working or operating equipment in areas that may contain invasive plant species be trained in the identification and modes of dispersal of common, highly-prolific aquatic and terrestrial invasive plant species commonly found along road sides and in utility ROWs. See tables below for identification of the common invasive plants in Connecticut and Massachusetts. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-28 Invasive Species in Massachusetts1 Botanical Name Common name Aegopodium podagraria Bishop’s goutweed; bishop’s weed Acer platanoides Norway maple Acer pseudoplatanus Sycamore maple Ailanthus altissima Tree of heaven Alliaria petiolata Garlic mustard Berberis thunbergii Japanese barberry Cabomba caroliniana Carolina fanwort; fanwort Celastrus orbiculatus Oriental bittersweet; Asian or Asiatic bittersweet Cynanchum louiseae Black swallow-wort; Louise’s swallow-wort Cynanchum nigrum – see Cynanchum louiseae Black swallow-wort; Louise’s swallow-wort Elaeagnus umbellata Autumn olive Euonymus alatus Winged euonymus; burning bush Euphorbia esula Leafy spurge; wolf's milk Fallopia japonica - see Polygonum cuspidatum Japanese knotweed; Japanese or Mexican bamboo Ficaria verna - see Ranunculus ficaria Lesser celandine; fig buttercup Frangula alnus European buckthorn; glossy buckthorn Glaucium flavum Sea or horned poppy; yellow hornpoppy Hesperis matronalis Dame’s rocket Iris pseudacorus Yellow iris Lepidium latifolium Broad-leaved pepperweed; tall pepperweed Lonicera japonica Japanese honeysuckle Lonicera morrowii Morrow’s honeysuckle Lonicera x bella [morrowii x tatarica] Bell’s honeysuckle Lysimachia nummularia Creeping jenny; moneywort Lythrum salicaria Purple loosestrife Myriophyllum heterophyllum Variable water-milfoil; two-leaved water- milfoil Myriophyllum spicatum Eurasian or European water-milfoil; spike water-milfoil Nasturtium amphibium - see Rorripa amphibia Water yellowcress; great yellowcress Nasturtium officinale - see Rorripa nasturtium- aquaticum Phalaris arundinacea Reed canary-grass Phragmites australis Common reed Section 3 Construction Considerations Eversource Best Management Practices Manual 3-29 Invasive Species in Massachusetts1 Botanical Name Common name Polygonum cuspidatum Japanese knotweed; Japanese or Mexican bamboo Polygonum perfoliatum Mile-a-minute vine or weed; Asiatic tearthumb Potamogeton crispus Crisped pondweed; curly pondweed Ranunculus ficaria Lesser celandine; fig buttercup Reynoutria japonica – see Polygonum cuspidatum Japanese knotweed; Japanese or Mexican bamboo Rhamnus cathartica Common buckthorn Rhamnus frangula – see Frangula alnus European buckthorn; glossy buckthorn Robinia pseudoacacia Black locust Rorippa amphibia Water yellowcress; great yellowcress Rosa multiflora Multiflora rose Salix atrocinerea/Salix cinerea Rusty Willow/Large Gray Willow complex Sisymbrium amphibium - see Rorripa amphibia Water yellowcress; great yellowcress Trapa natans Water-chestnut Vincetoxicum nigrum – see Cynanchum nigrum Black swallow-wort; Louise’s swallow-wort 1 Based on the Massachusetts Invasive Plants Advisory Group (MIPAG); Last Updated 6/2021 Invasive Species in Connecticut1 Botanical Name Common name Acer platanoides Norway maple Aegopodium podagraria Goutweed/Bishops Weed Ailanthus altissima Tree of heaven Alliaria petiolata Garlic mustard Ampelopsis brevipedunculata Porcelainberry Artemisia vulgaris Mugwort Berberis thunbergii Japanese barberry Berberis vulgaris Common barberry Cabomba caroliniana Fanwort Cardamine impatiens Narrowleaf bittercress Celastrus orbiculatus Asiatic bittersweet Centaurea stoebe Spotted knapweed Cynanchum louiseae Black swallow-wort Section 3 Construction Considerations Eversource Best Management Practices Manual 3-30 Invasive Species in Connecticut1 Botanical Name Common name Cynanchum rossicum Pale swallow-wort Elaeagnus umbellata Autumn olive Euonymus alatus Winged euonymus Euphorbia esula Leafy spurge Frangula alnus Glossy Buckthorn Froelichia gracilis Slender snake cotton Hesperis matronalis Dame’s rocket Hydrilla verticillata Hydrilla Iris pseudacorus Yellow iris Lepidium latifolium Perennial pepperweed Lonicera japonica Japanese honeysuckle Lonicera maackii Amur honeysuckle Lonicera morrowii Morrow’s honeysuckle Lonicera x bella Belle honeysuckle Lythrum salicaria Purple loosestrife Microstegium vimineum Japanese stiltgrass Myosotis scorpioides Forget-me-not Myriophyllum heterophyllum Variable-leaf watermilfoil Myriophyllum spicatum Eurasian watermilfoil Phalaris arundinacea Reed canary grass Phragmites australis Common reed Polygonum caespitosum Bristled knotweed Polygonum perfoliatum Mile-a-minute vine Potamogeton crispus Curly-leafed pondweed Ranunculus ficaria Fig buttercup Rhamnus cathartica Common buckthorn Robinia pseudoacacia Black locust Rosa multiflora Multiflora rose Rubus phoenicolasius Wineberry Trapa natans Water chestnut Tussilago farfara Coltsfoot 1 Based on the Connecticut Invasive Plants Council in accordance with Connecticut General Statutes §22a-381a through §22a-381d. The list was most recently re-printed in October 2018. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-31 Avoidance and Minimization • If possible, avoid or minimize contact with invasive species by physically avoiding locations with invasive plant infestations. • In locations where invasive infestations exist, design the project to minimize contact with invasive species by choosing access routes and staging areas that are outside areas of infestation. • Sequence work to the extent possible such that work using clean equipment and materials proceeds in un-infested areas prior to moving into infested areas and not vice versa. • If it is unknown whether invasive species exist, design the project to limit travel across vegetated areas to the extent possible. • When possible, time work under conditions that minimize the risk of spread, (frozen ground, snow cover, absence of seeds or propagules). Vegetation Management • Control of invasive plants by chemical means should be performed by a licensed applicator in accordance with the requirements of the CT DEEP Pesticide Management Program, the Massachusetts Pesticide Control Act (MPCA; M.G.L. Chapter 132B) and 333 CMR 2.00, ROW Vegetation Management regulations (333 CMR 11.00), and the MAWPA. • Mechanical mowing of vegetation should adhere to principals of avoidance and minimization. Where possible avoid mowing invasive plants, especi ally plants that have the ability to sprout from stem and root fragments. For other invasive species, mowing should occur prior to seed set if possible. • If woody vegetation is removed from a project site, transport it in compliance with invasive pest or disease quarantine zones established by the United States Department of Agriculture (USDA), the Connecticut Agricultural Experiment Station, MA DCR, and MA DAR. • Any restoration seed mixes used should be free of any species identified as invasive by the Connecticut Invasive Plants Council in accordance with Connecticut General Statutes §22a-381a through §22a-381d (in Connecticut) or the Massachusetts Invasive Plants Advisory Group (in Massachusetts). Soil Disturbance and Management • Where possible, avoid soil disturbance as it may increase the chances of colonization by invasive seeds or propagules. • Stabilize disturbed soils as soon as possible by seeding and/or using mulch, straw or gravel that is free of invasive plant material. • Where possible, when excavating soils, top layers of soil containing plant material and roots should be segregated from sub soils and left on site. • Cover soil and other material containing invasive plant material during transport. • Do not transport fill and material containing invasive plant material onto a project site. • If fill and materials containing invasive species must be transported off site, do not reuse, stockpile or dispose of these materials in such a manner that could promote Section 3 Construction Considerations Eversource Best Management Practices Manual 3-32 the spread of invasive plants. Decontamination Procedures • When utility maintenance activities require work in areas infested with invasive species, implement decontamination procedures per NHDOT’s Best Management Practices for Roadside Invasive Plants manual. • In order to minimize the spread of invasive plant seeds and material: o Clean vehicles, equipment, materials, gear, footwear or clothing of all visible soil and plant material on site in the infested area, or as near as practical to the infested area, prior to leaving the project site. o Do not decontaminate equipment next to streams or water bodies that could potentially transport seeds or propagules. o Decontaminate equipment and materials that may be contaminated by aquatic plant materials adjacent to the surface water they were exposed to prior to use in another surface water body. o Do not transport water withdrawn from a surface water body and discharge it to another water body. Methods of Cleaning • Use a brush, broom or hand tools to manually clean. • Clean debris off equipment such as construction matting by shaking or dropping mats in a controlled manner to dislodge attached soil and debris. • Compressed air. • Containment must be in compliance with wastewater discharge regulations when using low-or high-pressure wash stations. 3.11 Work Pads 3.11.1 De-Energized and Energized Applications: Work in wetlands • Reconnaissance of each work pad area in or adjacent to wetlands should be performed to determine if the construction mat work pad areas could be located outside of wetland resource areas. Wetland disturbances should be avoided or minimized where practicable. Coordinate work pad locations and/or configurations with Eversource Environmental Licensing and Permitting. Limitations: • Requires heavy machinery for installation. • Significant amount of time required for installation and removal. • Pads for live line work require a considerably larger footprint. • Several layers of matting may be needed in deep, construction areas. • Animals may be injured or killed when attempting to cross work pads. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-33 • May not be suitable in deep/open water wetlands. • Must be underlain with non-woven geotextile if within an ORW (MA only). How to Use: • Work at structures may require placement of construction mats to provide safe and stable work pad areas for employees and contractors. • Live line work, which is work that is done while the line is energized, requires a much larger work pad area. Efforts should be avoid or minimize impacts to wetlands to the extent practicable. • Sizes of work pads vary based on the type of work being proposed. • Work pad areas may extend into wetlands where structures that require maintenance either fall within or are in proximity to wetlands. In these cases, untreated wooden construction mats shall be used to limit disturbance. • Install silt fencing around work pads in identified amphibian and reptile priority habitat and where matting is greater than one mat thick. The exclusionary silt fencing will deter animals from moving across work pads and reduce the likelihood of being crushed by heavy equipment. • Following construction activities all mats at each work pad and vehicle access locations must be removed. • Remove mats by “backing” out of the site and removing mats one at a time. Regrade soils to pre-existing contours while taking care not to compact soils, if necessary. • In areas with invasive species, plant material should be removed from mats following removal from the infested area to prevent the spread of invasive species. Refer to the tables in this section for additional details regarding invasive plant species. 3.11.1.1 Best Management Practices – Work Pads De-energized work requires smaller work pad areas, while live line work (i.e., work that is done while the line is energized) requires a much larger work pad areas. De-energized construction mat work pads (see Figure A14 Appendix A) 3.12 Structure-Related Work 3.12.1 Wetland Structure-related activities that may occur in wetlands include structure replacement/ installation (including casing installation), guy wire anchor installation, counterpoise installation, and pole butt removal. Access to these areas and completion of the activities can cause disturbance to wetland vegetation and soils. Therefore, structure-related activities in wetlands should entail use of adequately sized work pads and proper dewatering methods if/as needed. Inspection of the construction access and asso ciated dewatering measures should occur daily during construction to ensure that controls are in working order and repairs to damaged/deteriorating controls are made in a timely matter. Repairs may include re-grading the traveled surface to eliminate ruts as well as those repairs required by each erosion and sedimentation measure used. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-34 Structure Replacement/Installation Replacement structures will often be replaced within a few feet of the original structure to maintain the required distances and line sags between other existing structures. Therefore, options for relocating proposed replacement structures are limited. Pole replacement will also require placement of construction mats in wetlands to provide a safe work pad for the required structure replacement activities. Usually, there are no alternatives that allow for this work to be conducted from nearby upland areas or to install the replacement structures in upland areas. Each structure replacement area should be assessed to determine the required footprint needed for construction mat work pads. Typical installation is as follows: • At each pole location, remove wetland topsoil with an excavator and stockpile. Segregate wetland soils as necessary. • If a borehole is drilled, collect and dispose of drilling spoils in an upland area. • A galvanized steel casing is then driven into place at least 12 inches below the ground surface. The new pole is installed within the casing with a crane. The casing is then backfilled with crushed rock and compacted. • Stockpiled wetland topsoil is placed above the casing to the ground surface. No net fill in wetlands occur, as the original poles are removed. • Following installation of the new structures, the old structures are removed. Each pole is cut with a chainsaw and allowed to fall to the ground, which in wetland areas is protected by construction mats. If the pole is to be bucked into sections, conduct sawing activities in uplands when feasible. Pole butts will remain in place; if removing the pole butt will cause more damage than if left in place. • Remove the pole and all appurtenant accessories (e.g., cross-arms, insulators) and properly dispose off-site. Remove each pole butt by pulling with an excavator positioned on a construction mat. If it is apparent that pole removal will compromise the integrity of the new pole installation, or that removal will result in additional disturbance to wetland areas, cut off the old pole at least 12 inches below ground level and backfill to match adjacent grades. Guy Wire Anchor Installation Guy wire anchors supporting the structures may also require replacing. There are two types of anchors: 1) helical and 2) plate type. Helical anchors are preferred over plate anchor because the installation of the helical anchor results in less disturbance to the wetland. • Load test the existing anchor to determine whether it will support the pole structure. Consult with Eversource Engineering to determine load testing requirements. In the event the existing anchor cannot be re-used, remove it and install a new anchor. • Screw in place a special triple helix (“screw type”) anchor with an anchor installation rig operated from the matting area. Add rod sections as needed until proper holding capacity of the anchor is achieved. Consult with Eversource Engineering to determine anchor installation requirements. o Helical anchors are turned into the ground with only the rods protruding. Disturbance to the wetland from the helical anchor is minimal. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-35 • Plate anchors are used in wetlands when proper holding cannot be achieved with screw anchors. To install a plate anchor, a pit is excavated to a sufficient depth and if necessary, a concrete footing would be installed several feet below surface grade. Consult with Eversource Engineering to determine plate anchor installation requirements. o When excavating to install plate anchors, segregate the top 12 inches of wetland topsoil from the underlying material. When the plate anchor has been set, backfill the excavation with underlying material. Utilize segregated wetland topsoil to restore pre-construction grades. Counterpoise Installation/Grounding To install grounding equipment in wetlands, use hand digging or minimally invasive methods to dig around the structure and restore soil to previous grades. In some cases, grounding rods can be driven directly into the ground with hand tools. Where work is occurring in the vicinity of wetland areas, sedimentation and erosion controls will be used to limit disturbance to wetlands. Underground Facility Repair/Replacement Underground facilities such as cables and conduits may be present beneath wetland areas. In the event underground facilities require repair, BMPs are required for both access and construction. Construction mats are used for access where warranted, and sedimentation and erosion controls are used to isolate the work area. During excavation activities, excavate wetland topsoil and stockpile separately from subsurface soils. Dewatering is often required during excavation and repair activities. An alternative to repairing a subsurface line by excavation is to install a new line via trenching or horizontal directional drilling (HDD). The decision to use one of these alternatives is made on a case by case basis. Consult with Eversource Environmental Licensing and Permitting to determine if any permits will be needed. Pole Butt Removal When transmission poles are decommissioned or otherwise taken out of service, in most cases the entire pole shall be removed. Treated wood pole butts shall be removed completely from the ground and properly disposed at an off-site location. Locations where the removal of pole butts may cause significant disturbance to wetlands or other sensitive environmental areas will be considered for exception to this practice on a site -by-site basis. The Transmission Line Construction and Maintenance Manager, in consultation with Eversource Environmental Licensing and Permitting, will be responsible for determining if a pole butt can be removed if located in a sensitive environmental area. All pole butt holes must be backfilled and compacted (every 3 feet) with appropriate fill material. Existing material on-site can be reused if it does not include materials that can rot (e.g., vegetation) and cause settling. Disposal Treated and non-treated wood products owned by the Transmission Group shall be stored in an area(s) designated by the Transmission Line Construction/Contract Field Services Supervisor until collected by an approved disposal vendor. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-36 Concrete Wash Outs Concrete wash outs shall be used for the management of concrete waste. Concrete and concrete wash out water shall not be deposited or discharged directly on the ground, in sensitive environmental areas, or in catch basins or other drainage structures. Where possible, concrete wash outs shall be located away from sensitive environmental areas, including buffer zones. Consult with Eversource Environmental Licensing and Permitting to determine concrete wash out locations prior to their use. Following the completion of concrete pouring operations, the wash outs shall be properly disposed of off-site with other construction debris. 3.13 Underground Cable and Gas Piping-Related Work Gas piping-related activities will typically occur within roadways or along roadway shoulders. There may be some instances where wetland permitting is required when wetlands are located adjacent to or in the vicinity of roadways. However, when work is performed within the roadway/shoulder, permitting is typically not required. Verify permitting requirements with Eversource Environmental Licensing and Permitting. In all cases, BMPs should be followed to ensure environmental compliance. Typical examples of underground cable and conduits include: High-Pressure, Fluid-Filled Pipe-Type Cable: A high-pressure, fluid-filled (HPFF) pipe-type of underground transmission line, consists of a steel pipe that contains three high-voltage conductors. The fluid also transfers heat away from the conductors. The fluid is usually static and removes heat by conduction. XLPE Cable (cross-linked polyethylene): Hydronic tubing that is manufactured from polyethylene plastic with a three-dimensional molecular bond that is created within the structure of the plastic. The cross-linked polyethylene (XLPE) underground transmission line is often called solid dielectic cable. The solid dielectric material replaces the pressurized liquid or gas of the pipe-type cables. XLPE cable has become the national standard for underground electric transmission lines less than 200 kV. Roadways and Shoulders When working in roadways, particularly in residential areas, the following activities should be performed in addition to standard construction BMPs: • Repave disturbed paved areas and return to original elevations on the same day that construction is performed. • Restore all non-paved areas to pre-existing (or improved) conditions. Replace any sod or other plantings in kind or with an acceptable alternative. • Employ dust control as necessary to minimize airborne dust. • Streets should be swept daily or as necessary to remove dirt and debris from resulting from construction from the roadway surface. Dirt and debris swept from the roadway surface should be collected and prope rly disposed of as construction waste. Under no circumstances should dirt and debris be swept off of the roadway surface to the road shoulder or deposited in any catch basins. • Discharge trench dewatering volumes to an appropriate dewatering structure setu p on adjacent undeveloped, unimproved uplands away from wetlands (refer to Appendix A). Consult with Eversource Environmental Licensing and Permitting staff Section 3 Construction Considerations Eversource Best Management Practices Manual 3-37 to determine appropriate locations for placement of dewatering structures. • Trench dewatering may also be discharged to areas of open trench to allow for infiltration. • For minor volumes or short-term duration dewatering needs, trench dewatering may be pumped to frac tanks for transport off-site and discharge to an appropriate dewatering structure located at a contractor yard or similar location. • Trench dewatering may only be discharged to stormwater catch basins after all necessary federal, state and local permits have been obtained to do so (this typically requires design and implementation of an effe ctive treatment system to remove all potential contaminants, such as suspended solids or other chemical contaminants). Consult with Eversource Environmental Licensing and Permitting if discharge to catch basins is required. Under certain circumstances, gas piping must be installed beneath existing culverts within roadways. Take care to ensure that any saturated material excavated from the trench be properly stored and disposed as to not cause sedimentation issues. Implement dewatering methodologies, as required. There may be cases where a drainage ditch or swale must be crossed to gain construction access from paved roads onto ROWs along the roadway shoulder. Install construction mats, mat bridges, or temporary culverts, as necessary, t o facilitate access. Culverts should be for temporary use, sized for peak flow, and removed after construction is complete. Consult with Eversource Environmental Licensing and Permitting prior to installation. Bridges and Culverts Attachment of gas piping to bridges or culverts is the environmentally preferable method for crossing a wetland or watercourse. Consult with the appropriate people (engineers, the Department of Transportation (DOT), etc.) to determine if attachment to a bridge or culvert is a technically feasible option at the desired crossing location. Eversource Environmental Licensing and Permitting should also evaluate the impacts to FEMA flood storage quantities and potential Coast Guard permitting requirements. Ensure that proper erosion and sedimentation controls are in place on either side of the bridge or culvert throughout construction. Rivers and Streams There are two primary approaches for crossing a river or stream with a gas pipeline: direct bury (open trenching) and trenchless methods (e.g., HDD, standard bore/pipe jacking). Direct bury methods involve erecting a coffer dam to isolate the work area and redirecting water flow using gravity or pumping to move water from one side of the work area to the other. Direct bury methods have larger direct environmental impacts than trenchless methods. Typical coffer dam examples are included in Figures A42 and A43 in Appendix A. Trenchless methods use specialized equipment to install piping beneath a waterbody (or a major roadway, railroad, etc.). The most common method used for gas piping is HDD which uses remote controlled, steerable drilling equipment to install pipe along a long arc alignment. The drilling process can be divided into three steps: pilot, reaming, and pull- in. The first step is to drill a pilot bore-hole. Next, a larger diameter fly cutter is used to Section 3 Construction Considerations Eversource Best Management Practices Manual 3-38 enlarge the opening. A specialized bentonite slurry drilling fluid is injected into the bore- hole to stabilize the surrounding soil and to lubricate and cool the drill bit. For the final step, a barrel reamer is used to further enlarge the bore -hole and to pull the pipe into place. A notable environmental concern with HDD is called “frac-out.” This occurs when drilling fluid breaks through the soil surface and into the waterbody. Regulatory agencies may require a “frac-out plan” which details preventative controls and response measures should frac-out occur. A typical frac out plan is included in Appendix D; however, HDD contractors should be required to provide a detailed frac-out plan specific to the project and their practices. These plans may be subject to environmental regulatory agency review. Consult with Eversource Environmental Licensing and Permitting for permit requirements. 3.14 Construction Material along the ROW Once a site is prepared by clearing and/or installing erosion and sediment controls, materials may be stored along the ROW prior to the start of construction. Such materials may include the following: piping, poles, cross-arms, cable, insulators, stone, and other engineered backfill materials. In general, the stockpiling of stone and other unconsolidated material on construction mats should be avoided. If it is determined necessary due to access and work pad constraints, the material should be placed on a geotextile fabric and be properly contained with a sedimentation barrier such as straw wattle or bales. No construction materials should be placed in wetlands or other sensitive resource areas. 3.15 Winter Construction 3.15.1 Snow Management Snow should not be stockpiled or disposed in any waterbody or near water supply sources. These include wetlands, rivers/streams, the ocean, reservoirs, ponds, stormwater catch basins, wellhead protection area, in high or medium yield aquifer, or within 200 feet of a private well. In addition to water quality impacts and flooding, snow disposed in surface water can cause navigational hazards when it freezes into ice blocks. Maintain a minimum buffer of 25 feet between any snow disposal area and the high water mark of any surface water. A silt fence or equivalent barrier should be installed between the snow storage area and the high water mark of rivers, streams, ponds, or the ocean. Consult with Eversource Environmental Licensing and Permitting regarding any specific state and local snow management requirements. Avoid disposing of snow on top of storm drain catch basins or in storm water drainage swales or ditches. Snow combined with sand and debris may block a storm drainage system and cause localized flooding. A high volume of sand, sediment, and litter released from melting snow also may be quickly transported through the system into surface water and could also result in fines or a violation. All debris in a snow storage area should be cleared from the site and properly disposed of no later than May 15 of each year. Care shall be taken not to plow road materials away when removing snow. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-39 3.15.2 De-Icing Where permitted, calcium chloride is the preferred de-icing agent when applied according to manufacturer’s guidelines in upland areas. Sand should be used on construction mats through wetland areas. Consult with Eversource Environmental Licensing and Permitting on de-icing agents when working in a facility or substation near resource areas. Many municipalities have specific de-icing agent requirements for work within 100 feet of wetlands and other sensitive environmental areas. 3.15.3 Snow and Ice Management on Construction Mats Promptly and properly remove snow from construction mats to avoid ice formation. Remove snow from construction mats before applying sand to avoid forming ice. A round street sweeping brush mounted on the front of a truck may be an effective way to remove snow from construction mats. Propane heaters may also be suitable solutions for snow removal and/or de-icing of construction mats. Sand should be collected from the construction mats and disposed of in an upland area prior to removing construction mats from wetlands. Once construction mats are removed, wetlands shall be inspected for sand buildup that may have fallen through construction mats. Sand deposited in wetlands or other sensitive environmental areas shall be completely removed by the contractor. Consult with Eversource Environmental Licensing and Permitting prior to commencing work in wetlands or other sensitive environmental areas. 3.16 Dust Control Dust control measures are used to reduce surface and air movement of dust from exposed soil surfaces during land disturbance, demolition, and construction activities. These practices reduce the amount of dust in the air and decrease the potential for accidents, respiratory problems, and airborne sedimentation. Construction activities should be scheduled appropriately to minimize the amount of site surface exposed at one time in order to reduce the amount of areas requiring dust control. Use dust control measures on disturbed soil surfaces and exposed soil surfaces, especially during hot or dry weather periods and in areas with excessively well-drained soils. Repetitive treatments should be used as needed, or required by permits, and until the surface is permanently stabilized. Type Description/Use Vegetative Cover • Most effective and practical method. • Use in disturbed areas not subject to traffic. • Follow seeding requirements as directed by local guidelines or permit requirements. Stone • Cover soil surface with crushed stone/coarse gravel. Water/Sprinkling • Sprinkle exposed soils until wet (Water trucks may be used depending on size of the site). • Do not excessively wet the soil as this causes run-off and also wastes water. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-40 Barriers • Board fences, wind fences, and sediment fences control air currents and blowing soil. • Wind barriers protect soil downgradient for a distance of ten times the barrier height. • Perennial grasses and stands of existing trees also serve as wind barriers, stressing the importance of planning work phasing properly and minimizing the amount of exposed soil. Plastic Covering • Cover soil piles with sheets of plastic/tarp to minimize dust. Calcium Chloride • Loose, dry granules of calcium chloride may be applied with a mechanical spreader. • Apply at a rate that keeps the surface moist but not high enough to cause water pollution or plant damage. This method should be done under consultation with an expert in order to maintain this balance and to determine if the site is applicable. 3.16.1 Soil Stockpile Management Some projects may involve excavation and stockpiling of soil. Stockpiles should be located outside sensitive areas to the extent practicable and managed to prevent erosion and sedimentation of adjacent areas. Typical measures include the installation of protective measures (e.g., siltation fence and/or straw bales) around the perimeter of the stockpile. The stockpile must be seeded if left in place for more than 30 days. No snow or soil piles, construction materials, or equipment should be stored in the immediate vicinity at the top of a terrace escarpment slope. 3.16.2 Stockpiles on Construction Mats When soil (or gravel) stockpiles must be staged on construction mat work pads in wetlands, stockpiles should be placed atop areas of matting underlain with non -woven geotextile (either directly atop the mats or between layers of matting) to minimize the potential for material to filter through gaps in matting and deposit in wetlands. Use of construction mat stringers as physical barriers at the edge of the work pad should also be considered. These barriers are recommended to minimize the potential for stockpiled material to get pushed off the work pad into wetlands. Consult with Eversource Environmental Licensing and Permitting for site-specific guidance. 3.16.3 Regulated Soils Management When polluted/contaminated soil is encountered, it must be handled in accordance with the appropriate regulatory requirements. In addition to the measures discussed above, contaminated soils should be stockpiled on and covered by polyethylene sheeting. Sheeting used to cover the stockpile should be weighted down to prevent the wind migration of contaminated dust. For soil stockpiles in substations, contact Eversource Environmental Licensing and Permitting. If soil/water must be stored and/or disposed, comply with existing soil and groundwater management guidelines. Coordinate with the Environmental Affairs Department (EAD) to ensure appropriate procedures are followed. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-41 3.16.4 Best Management Practices – Soil Stockpile Management The following BMP is applicable to soil stockpile management and is described at: Soil Stockpile Management (see Figure A19 in Appendix A) 3.17 Anti-Idling Laws Connecticut and Massachusetts have promulgated anti-idling laws for the purpose of improving air quality by reducing unnecessary air pollution from idling vehicles. State Idling Time Limit (in minutes) Connecticut 3 Massachusetts 5 Details of these laws and the statutory exceptions to the limits noted above are presented in the following sections. 3.17.1 Connecticut The Regulations of Connecticut State Agencies (RCSA) section 22a-174-18(b)(3) states: a mobile source shall not operate for more than three (3) consecutive minutes when such mobile source is not in motion except if the vehicle is operating for one of the conditions exempted in the regulation. These exemptions for mobile sources not in motion include: • When a mobile source is forced to remain motionless because of traffic conditions or mechanical difficulties over which the operator has no control. • When it is necessary to operate defrosting, heating or cooling equipment to ensure the safety or health of the driver or passengers . • When it is necessary to operate auxiliary equipment that is located in or on the mobile source to accomplish the intended use of the mobile source. • To bring the mobile source to the manufacturer’s recommended operating temperature. • When the outdoor temperature is below 20 degrees Fahrenheit. • When the mobile source is undergoing maintenance that requires such mobile source be operated for more than three (3) consecutive minutes. • When a mobile source is in queue to be inspected by U.S. military personnel prior to gaining access to a U.S. military installation. 3.17.2 Massachusetts The Massachusetts Anti-Idling Law (M.G.L. Chapter 90, Section 16A and its implementing regulations set forth at 310 CMR 7.11 applies to all vehicles and limits unnecessary engine idling of stopped vehicles to five (5) minutes. This law shall not apply to: • Vehicles being serviced, provided that operation of the engine is essential to the proper repair thereof. Section 3 Construction Considerations Eversource Best Management Practices Manual 3-42 • Vehicles engaged in the delivery or acceptance of goods, wares, or merchandise for which engine assisted power is necessary and substitute alternate means cannot be made available. • Vehicles engaged in an operation for which the engine power is necessary for an associate power need other than movement, and substitute alternate power means cannot be made available provided that such operation does not cause or contribute to a condition of air pollution. SECTION 4 Eversource Best Management Practices Manual 4-1 Section 4 Inspection and Maintenance A pre-construction meeting will be held to discuss how often and who is responsible for monitoring erosion and sediment controls to document their condition and recommend maintenance or other corrective actions, as necessary. All BMPs will be inspected at least once per week during active construction and until disturbed areas have stabilized following post-construction site restoration. Construction sites will be inspected after major storm events (rainfall events greater than 0.25 inches (MA) or 0.50 inches (CT)), or as directed by Eversource Environmental Licensing and Permitting. 4.1 During Construction Construction sites, construction access roads, and the associated erosion and sediment controls should be inspected by the person(s) designated at the pre-construction meeting, as required by permit conditions. Any damage observed must be repaired in a timely manner, at least within 48 hours of observation. Repairs may include re-grading and/or top dressing the surface with additional aggregate to eliminate ruts as well as t hose repairs required by each erosion and sediment measure used. All inspections will be documented in a written report submitted to Eversource Environmental Licensing and Permitting and saved to the project folder. Copies will be distributed to the relevant contractors if/as directed by Eversource Environmental Licensing and Permitting. 4.1.1 Maintenance of Erosion and Sedimentation Controls Spare erosion and sedimentation control materials such as straw wattles, straw bales and silt fencing should be kept on site or be readily available so they may be replaced if they become non-functional due to deterioration or damaged during a storm, extreme water or wind, or other unexpected events. 4.1.2 Rapid Wetland Response Restoration In the event of unintended discharges of sediment into wetlands, Eversource Environmental Licensing and Permitting will direct the contractor(s) to quickly control, contain and remove sediment using non- or marginally invasive methods. Responding quickly to unintended discharges minimizes the difficulty and cost of restoration if the sediment is left in place for an extended period of time. Eversource Environmental Licensing and Permitting will direct sediment removal activities at the time of discharge and will notify the appropriate regulators of the discharge and the recommended corrective actions. 4.1.3 Vehicle Storage and Refueling All storage and refueling of vehicles and other equipment must occur outside of and as far away as practical from sensitive environmental areas such as wetlands, unless specifically authorized by Eversource Environmental Licensing and Permitting and an alternate protocol is developed and approved internally. The recommended minimum distance from wetlands for storage of fuel and refueling is 100 feet. Additionally, equipment should be checked regularly for evidence of leaks. Construction material storage should also be located at least 100 feet from wetlands. Section 4 Inspection and Maintenance Eversource Best Management Practices Manual 4-2 Storage of larger, less mobile equipment such as drill rigs or large cranes, may be permitting within wetlands subject to prior approval from Eversource Environmental Licensing and Permitting. Secondary containment shall be in place at each piece of equipment during non-working hours. Refueling of larger, less mobile equipment such as drill rigs or large cranes, may be allowed within wetlands only with prior approval from Eversource Environmental Licensing and Permitting and if specified precautions and protocols are followed. A proper location for refueling should be identified and designated before site work begins. At a minimum, if refueling must be conducted in wetlands, the contractor shall provide adequate secondary containment during refueling operations and shall maintain a spill kit on-site at all times. 4.1.4 Spills Spill kits consist of emergency cleanup and spill containment materials that can be used in the event of a fuel or other chemical spill. Spill kits must be kept on site and accessible at all times in case of an emergency spill. Such kits should generally contain multiple absorbent socks and/or pillows and wipes and temporary disposal bags. Follow the applicable Eversource Contractor Work Rules. 4.1.5 Post-Construction Post-construction inspections of restored areas will be conducted at regular intervals throughout the growing season, as required by any applicable permits, and/or after major storm events. Sites should be inspected for success or failure of revegetation, invasive species colonization, and erosion and sedimentation. In the event additional measures are required to achieve site restoration and stabilization, corrective actions shall be identified and implemented. All information collected during inspections, regular maintenance, and repair procedures should be documented in project folders. In addition, photogra phic or diagrammatic logs may be kept to record certain events and for documentation of project progress and any noteworthy observations. The construction work is not complete until all areas are restored. SECTION 5 Eversource Best Management Practices Manual 5-1 Section 5 Rehabilitation and Restoration 5.1 Restoration All areas disturbed by construction, repair, and maintenance activities shall be substantially restored to pre-construction conditions. Please refer to Appendix A for photos and typical details for loaming, seeding, and mulching. Prompt restoration minimizes the extent and duration of soil exposure and prot ects disturbed areas from erosion due to stormwater runoff, ice, wind and gravity. Stabilization should be conducted as soon as practicable. Where appropriate, it is preferable to allow sensitive environmental areas, such as wetlands and rare species habitat to revegetate naturally. Consult Eversource Environmental Licensing and Permitting for project-specific restoration requirements. 5.1.1 Seed Mixes Several different seed mixes are available for upland and wetland restoration. State - specific comprehensive summaries of seed mixes for both temporary and permanent seeding of disturbed sites can be found within the following documents: • Massachusetts: Massachusetts Erosion and Sediment Control Guidelines for Urban and Suburban Areas, page 157: https://www.mass.gov/doc/complete- erosion-and-sedimentation-control-guidelines-a-guide-for-planners-designers- and/download • Connecticut: 2002 Connecticut Guidelines for Soil and Erosion Sediment Control, page 5-3-8: https://portal.ct.gov/DEEP/Water/Soil-Erosion-and-Sediment-Control- Guidelines/Guidelines-for-Soil-Erosion-and-Sediment-Control Upland Seed Mix: If significant grading or upland alteration has occurred, annual rye grass seed shall be placed for temporary stabilization following manufacturer’s recommendations after re-grading activities. Wetland Seed Mix: If significant grading or wetland alteration has occurred, a wetland seed mix shall be placed following manufacture’s recommendations after re-grading activities. 5.1.2 Upland The following restoration techniques apply to restoration projects in upland areas. • Soil excavated during construction and not used as backfill must be eve nly spread across disturbed areas to restore grades. Topsoil shall be stripped and separated to the extent practicable for re-use. Permanent soil protection shall be provided for all areas disturbed by construction activities. All areas will be seeded either by hydroseeding or broadcast seeding. Interim stabilization measures are required if areas cannot be seeded due to the time of year . Interim measures may include the application of mulch. • Topsoil removed during construction activities will be replac ed, seeded, and mulched. • All areas that are broadcast seeded shall be treated with a layer of mulch, such as Section 5 Rehabilitation and Restoration Eversource Best Management Practices Manual 5-2 straw, up to one (1) inch thick to enhance moisture retention, dissipate disturbance from precipitation, and detract birds foraging on broadcast seed. • Rehabilitation of access routes and other areas must be performed as soon as practicable after construction is completed, including reestablishment of water bars or other BMPs to control erosion of the access road, and the removal and restoration of temporary wetland or waterway crossings. o Temporary breaks in construction activities may warrant seeding and mulching of disturbed areas as interim erosion control measures. Consult with Eversource Environmental Licensing and Permitting to determine project-specific requirements. • Erosion control measures shall remain in place until soils are adequately stabilized, as confirmed by Eversource Environmental Licensing and Permitting. Once soils are stable, erosion controls – especially silt fence, which presents an obstacle to movement of small animals, shall be removed and properly disposed off -site. Stakes should be removed from straw bales and spread as mulch to remove barriers to wildlife movement. • The use of hay and/or hay products is strictly prohibited to prevent the spread of invasive plant species seed stock. • If a grading operation at a site is suspended for a period of more than twenty -nine (29) consecutive days, the disturbed area shall be stabilized by seeding, mulching, and/or other appropriate means within the first seven (7) days of the suspension of grading. • Within seven (7) days after a final grade is established in any grading operation, the disturbed area shall be stabilized by seeding, loaming, and/or other appropriate means. 5.1.3 Wetland/Watercourses Re-grading of Ruts: Upon removal of construction mats, or other BMPs, the wetland/watercourse should be inspected for rutting or disturbance from eroded upland soils. Any rutting should be re-graded to pre-existing contours and upland soils removed from wetland areas while taking care not to compact soils. The following restoration techniques apply to restoration projects in wetlands: Maintenance, Repair, and Emergency Projects (When No Permit is Required) • Remove mats by “backing” out of the site and removing mats one at a t ime. Re- grade soils to pre-existing contours while taking care not to compact soils. • Soils excavated from wetland areas shall be segregated and stockpiled separately (i.e., topsoil/muck apart from mineral subsoil) in a dry/upland area at least 100 feet from wetland boundaries unless other provisions have been made to facilitate restoration activities. • Excavated wetland soils that have been stockpiled during underground utility installations within wetlands shall be replaced in the same order (i.e., mineral subsoil beneath organic topsoil/muck) to the extent practicable and restored to pre-disturbance grades. o Grading activities should include the elimination of ruts within the Section 5 Rehabilitation and Restoration Eversource Best Management Practices Manual 5-3 area to be restored. • If replacement of soil associated with temporary wetland or watercourse crossings for access roads is necessary, disturbed areas must be restored to pre-disturbance grades, either seeded and mulched, or allowed to revegetate from the natural seed bank. • Disturbed wetland areas shall generally be allowed to revegetate from the natural seed bank. Measures to discourage the establishment or spread of plant species identified as non-native, invasive species by federal or state agencies shall be utilized. Consult with Eversource Environmental Licensing and Permitting to evaluate means and methods of wetland vegetate re-establishment. • Any restoration plantings or seed mixes used in restoration shall consist of species native to the project area and, if feasible, from local nursery stock. • Any stream banks and beds damaged shall be restored through use of 100 percent natural fiber geotextile erosion control blankets and/or coir logs. The use of erosion control products containing plastic and/or nylon is strictly p rohibited. • All seeded areas shall be treated with a layer of mulch (i.e., straw; the use of hay and/or hay products is strictly prohibited) up to one (1) inch thick to enhance moisture retention, dissipate disturbance from precipitation, and detract songbi rds foraging on broadcast seed. 5.2 Private Property 5.2.1 Improved Areas If access is over an off-ROW property, then it is the responsibility of a construction representative to determine if legal access rights are available to cross the property. Access to and along the ROW over private property must be improved to the extent necessary to ensure suitable passage for construction equipment, provide erosion control, and maintain proper drainage. Upon completion of construction activities, altered yards, lawns, agricultural areas, and other improved areas must be restored to a condition equal to or better than before their use for the construction project. 5.2.2 Overall Work Site Construction personnel should remove all work-related trailers, buildings, rubbish, waste soil, temporary structures, and unused materials upon satisfactory completion of work. All areas should be left clean, without any litter or equipment (e.g., wire, pole butts, anchors, insulators, cross-arms, cardboard, coffee cups, water bottles) and stabilized to match pre- construction conditions to the maximum extent practicable. Debris and spent equipment should be returned to the operating facility or contractor staging area for disposal or recycling as appropriate. 5.2.3 Material Storage/Staging and Parking Areas Upon completion of all work, all material storage yards, staging areas, and parki ng areas shall be completely cleared of all waste and debris. Unless otherwise directed or unless other arrangements have been made with an off-ROW or off-property owner, material storage yards and staging areas shall be returned to the condition that exis ted prior to the installation of the material storage yard or staging area. Regardless of arrangements Section 5 Rehabilitation and Restoration Eversource Best Management Practices Manual 5-4 made with a landowner, all areas shall be restored to their pre-construction condition or better. Any temporary structures erected by the contractor, inc luding fences, shall be removed by the contractor and the area restored as near as possible to its original condition, including seeding and mulching as needed. 5.3 Work in Agricultural Lands Transmission lines often cross agricultural lands. In some instances, this may affect ongoing agricultural activities in and around the ROWs. If a construction or maintenance project occurs within agricultural lands, Eversource will work closely with landowners, licensees and stakeholders to minimize agricultural impacts. Whenever practical, Eversource will make reasonable efforts to coordinate the schedule of construction-related activities around the growing and harvest seasons to minimize the impacts on agricultural operations. When this is not practical, Eversource will pursue reasonable measures to mitigate any impacts. Eversource recognizes that disturbed soils, or soils compacted by heavy construction equipment, may affect the soil’s ability to support certain agricultural activities. Eversource will take reasonable steps to avoid or minimize soil compaction an d will restore soils that are compacted by construction equipment. Typical measures to avoid or minimize soil compaction include the use of construction mats for access to, and work pads at, structures within the project scope. Eversource will also work with affected landowners to determine the appropriate method for restoring the soils and is open to discussing and implementing the landowners’ alternative restoration suggestions. After the transmission improvement is complete, Eversource will remove all construction-related equipment and debris from the ROW. APPENDIX A EXISTING ROADWAY ELEVATION VIEW PLAN VIEW DITCHFLOW FLOWF L OW FLOWCONSTRUCTION ACCESS ROAD CONSTRUCTION ENTRANCE TRACK PAD SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Const Entr.dwgDec 15, 2021-3:23pm Plotted By: ASapelli12/2021 NO SCALE LEVEL TO EXISTING GRADECRUSHED AGGREGATE TEMPORARY CULVERT IF NEEDED CRUSHED AGGREGATE NOTES: 1. CRUSHED AGGREGATE TO CONSIST OF 3-INCH TO 6-INCH STONE. 2. AGGREGATE TO BE UNDERLAIN WITH NON-WOVEN GEOTEXTILE FABRIC. NON-WOVEN GEOTEXTILE A01 A-1 WATER BARS SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Water Bars.dwgDec 15, 2021-3:21pm Plotted By: ASapelli12/2021 NO SCALE ROAD S U R F A C E WATER FLOWS OFF ROAD ONTO LEVEL SPREADER/VEGETATED SURFACE NOTE: FILL FOR BERMS SHALL BE A COMBINATION OF GRAVEL, SAND AND SILT TO ENSURE WATER TIGHTNESS AND STABILITY. 6' MIN.9"COMPACTED BERM EXCAVATED SWALE 18"ROAD SURFACE ELEVATION VIEW COMPACTED BERM A02 A-2 VEGETATED SWALES SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Vegetated Swale.dwgDec 15, 2021-3:30pm Plotted By: ASapelli12/2021 NO SCALE DRAINAGE SWALE AT ROADWAY 2'2'2'1'1' 2 1 2 1 4" TOPSOIL & SEEDED EXISTING GRADE ROADWAY EROSION CONTROL BLANKET VARIES 3'VARIES GRASS-LINED CHANNEL 4" TOPSOIL & SEEDED21 2 1 NOTE: 1. USE OF PRODUCTS WITH PLASTIC AND/OR NYLON NETTING IS PROHIBITED. A03 A-3 ALTURNAMAT SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Alturnamat.dwgDec 15, 2021-3:21pm Plotted By: ASapelli12/2021 NO SCALE 4'8'PLAN VIEW ELEVATION VIEW INDIVIDUAL MAT UTILITY POLE MUDDY/UNSTABLE GROUND IN OR NEAR WETLAND AREA UTILITY POLE A04 A-4 R PLAN VIEW ELEVATION VIEW CONSTRUCTION MAT (WETLAND CROSSING) SCALE: DATE: FIGURE:Tighe & Bond, Inc. J:\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Construction Mat-Wetland-A1.dwgApr 07, 2022-2:19pm Plotted By: AGordon12/2021 NO SCALE NOTES: 1. CONSTRUCTION MAT DIMENSIONS OF 12'x4'x8", 16'x4'x8" OR OTHER TO BE USED. EXISTING GRAVEL FILL (WHERE PRESENT) (8'-12' WIDE) INDIVIDUAL MAT TRANSVERSE CONSTRUCTION MATS EXISTING GRAVEL FILL (WHERE PRESENT) (8'-12' WIDE) MUDDY/UNSTABLE GROUND IN OR NEAR WETLAND AREA UPLAND DIRECTION OF TRAFFIC WET/MUDDYAREA A05 CONSTRUCTION MATS PLACED LONGITUNINALLY ALONG WHEEL TRACKS A-5 CONSTRUCTION MAT - AIR BRIDGE SCALE: DATE: FIGURE:Tighe & Bond, Inc. J:\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Elevated Animal Crossing.dwgNov 22, 2021-2:28pm Plotted By: TMP12/2021 A06 NO SCALE PLAN VIEW ELEVATION VIEW 10'± CONSTRUCTION MATS GROUND SURFACE 10'± NOTES 1. CONSTRUCTION MATS SHOULD BE PLACED CLOSELY TOGETHER SO THERE ARE NO GAPS BETWEEN EACH MAT SECTION. 2. CONSTRUCTION MAT DIMENSIONS OF 12'x4'x8", 16'x4'x8" OR OTHER TO BE USED. 3. AIR BRIDGING MAY ALSO BE USED TO AVOID IMPACTS TO UNDERGROUND UTILITIES, STONE WALLS, RARE PLANTS OR OTHER SENSITIVE FEATURES. CONSULT WITH EVERSOURCE ENVIRONMENTAL. 4. ADDITIONAL MEASURES MAY BE REQUIRED.16'-0"CONSTRUCTION MATS A-6 CONSTRUCTION MAT (AIR BRIDGE) CONSTRUCTION MAT ANCHORING SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Construction Mat Anchor.dwgFeb 04, 2022-10:09am Plotted By: ASapelli12/2021 NO SCALE A07 HELICAL ANCHOR (TYP) POINTS OF ATTACHMENT (TYP) CABLE OR ROPE (TYP) PLAN VIEW NOTES: 1. TYPICAL HELICAL ANCHOR AND CABLE CONFIGURATION FOR MAT CONTAINMENT IN FLOODPLAINS/LAND SUBJECT TO FLOODING. 2. TYPICAL POINT OF ATTACHMENT HEAVY STAPLES, EYEBOLTS OR OTHER SUITABLE HARDWARE TO SECURE ATTACHMENT OF MAT TO LINEAR CABLE. IF CHAIN POCKETS ARE PRESENT IN THE MATS CABLE OR ROPE CAN BE LOOPED THROUGH RODS. A-6A-7 WETLAND AREA PLAN VIEW NOTES: 1. DRAINAGE LAYERS MAY BE USED AS AN ALTERNATIVE TO CULVERTS, OR IN COMBINATION WITH CULVERTS, TO PROVIDE ADEQUATE CROSS-DRAINAGE. 2. FILTER FABRIC "JOINTS" SHOULD OVERLAP AT LEAST 18" (WHERE ONE PIECE OF FILTER FABRIC ENDS AND A NEW PIECE OF FABRIC IS ADDED TO CONTINUE THE ROAD). 3. EROSION AND SEDIMENTATION CONTROLS MAY BE INSTALLED ADJACENT TO THE SIDES OF THE ROAD WHEN CONDITIONS WARRANT. PERMEABLE ROAD SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Permeable Road.dwgDec 15, 2021-3:26pm Plotted By: ASapelli12/2021 NO SCALE ELEVATION VIEW DRAINAGE LAYER OF 3"-6" ROCK (MINIMUM 12" THICK) OR LOG CORDUOY (MINIMUM 2" LOG DIAMETER) GRANULR FILL TOP GEOTEXTILE LAYER BOTTOM GEOTEXTILE LAYER MUDDY/UNSTABLE GROUND IN OR NEAR WETLAND AREA DIRECTION OF TRAFFIC A08 A-7A-8 TEMPORARY CONSTRUCTION CULVERT SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Culv_Cros_Temp.dwgDec 15, 2021-3:24pm Plotted By: ASapelli12/2021 NO SCALE FLOWFLOW PLAN VIEW ELEVATION VIEW NOTES: 1. CAPACITY OF PIPES COMBINED SHOULD ACCOUNT FOR SIGNIFICANT STORM EVENTS. 2. INSTALLATION OF NEW CULVERTS MAY REQUIRE PERMITS. CONSULT WITH EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING PRIOR TO CONSTRUCTION. COARSE AGGREGATETOP OF BANK EARTHEN FILL COVERED WITH LARGE ANGULAR ROCKS DIVERSION BAR ROCK LAYER SHOULD BE HALF THE DIAMETER OF THE PIPE, 30CM, OR AS NEEDED TO SUPPORT LOADS - WHATEVER IS GREATER COARSE AGGREGATE EARTHEN FILL COVERED WITH LARGE ANGULAR ROCKS NON-WOVEN GEOTEXTILE FABRIC A09 A-8A-9 FLOWFLOW PLAN VIEW SECTION A-A NOTE: 1. INSTALLATION OF NEW OR REPLACEMENT STREAM CROSSINGS, INCLUDING BOX CULVERTS, IS SUBJECT TO ENVIRONMENTAL PERMITTING. CONSULT WITH EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING. PERMANENT, OPEN BOTTOM BOX CULVERT CROSSING SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Box Culvert _Permanent.dwgDec 15, 2021-3:21pm Plotted By: ASapelli12/2021 NO SCALE OPEN BOTTOM BOX CULVERT TOP OF BANK ACCESS ROAD GRADE TOP OF BANK ACCESS ROAD ARCH BOX CULVERT TOP OF BANK EDGE OF WATER A A A10 A-9A-10 PERMANENT OPEN BOTTOM BOX CULVERT ARCH CULVERT SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Arch Culvert.dwgDec 15, 2021-3:21pm Plotted By: ASapelli12/2021 NO SCALE NOTES: 1. CHAMBERS SHALL CONFORM TO THE REQUIREMENTS OF ASTM F2418 "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP) CORRUGATED WALL STORMWATER COLLECTION CHAMBERS", OR ASTM F2922 "STANDARD SPECIFICATION FOR POLYETHYLENE (PE) CORRUGATED WALL STORMWATER COLLECTION CHAMBERS". 2. CHAMBERS SHALL BE DESIGNED IN ACCORDANCE WITH ASTM F2787 "STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER COLLECTION CHAMBERS". 34"16"6"24" MINACCESS ROAD 3 4" CRUSHED STONE GEOTEXTILE FABRIC FOR SEPARATION CORRUGATED ARCH SYSTEM UNDISTURBED STREAM BED ORDINARY BORROW A11 A-10A-11 POLE FORD SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Pole Ford.dwgDec 15, 2021-3:26pm Plotted By: ASapelli12/2021 NO SCALE A12 NOTES: 1. POLES AND NONWOVEN GEOTEXTILE MUST BE REMOVED IMMEDIATELY AFTER USE. 2. LENGTH OF POLES SHALL BE AT LEAST 10 FEET. 3. USE OF HARDWOODS PROHIBITED. 4. CONSULT WITH EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING PRIOR TO INSTALLATION OF POLED FORDS. UNDISTURBED VEGETATION TOP OF BANK PLAN VIEW ELEVATION VIEW FLOW FLOW 10' MIN NONWOVEN GEOTEXTILE 8 TO 10-INCH POLES STREAM A-11A-12 LEGEND REPLACEMENT POLE LOCATION CONSTRUCTION MAT - 16'x4'x 8" TYPICAL SIZE.12'x4'x8" OR OTHER SIZE ACCEPTABLE. WORK SPACE REQUIREMENTS - LIVE LINE WORK (DETERMINED BASED ON PROJECT SPECIFIC NEEDS) LIMIT OF RIGHT-OF-WAY WETLAND AREA CONSTRUCTION MAT LAYOUT (LIVE LINE WORK) WETLAND BOUNDARY 16' WIDE ACCESS 16'x4' CONSTRUCTION MATS WORK PAD SIZE TO BE DETERMINED BY PROJECT SPECIFIC NEEDS SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Construction Mat-Live Line Work.dwgDec 15, 2021-3:24pm Plotted By: ASapelli12/2021 NO SCALE WETLAND BOUNDARY A13 A-12A-13 LEGEND REPLACEMENT POLE LOCATION CONSTRUCTION MAT - 16'x4'x 8" TYPICAL SIZE.12'x4'x8" OR OTHER SIZE ACCEPTABLE. WORK SPACE REQUIREMENTS - DE-ENERGIZED WORK(DETERMINED BASED ON PROJECT SPECIFIC NEEDS) LIMIT OF RIGHT-OF-WAY WETLAND AREA CONSTRUCTION MAT LAYOUT (DE-ENERGIZED LINE WORK) WETLAND BOUNDARY 16' WIDE ACCESS 16'x4' CONSTRUCTION MATS WORK PAD SIZE TO BE DETERMINED BY PROJECT SPECIFIC NEEDS SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Swamp Mat -Deenergized Work.dwgDec 15, 2021-3:28pm Plotted By: ASapelli12/2021 NO SCALE A14 A-13A-14 CONCRETE WASHOUT AREA SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Concrete Washout.dwgDec 15, 2021-3:23pm Plotted By: ASapelli12/2021 NO SCALE NOTES: 1. CONCRETE WASHOUT AREA(S) SHALL BE INSTALLED PRIOR TO CONCRETE PLACEMENT ON SITE. THE CONCRETE WASHOUT AREA SHALL BE ENTIRELY SELF-CONTAINED. 2. THE CONTRACTOR SHALL SUBMIT THE DESIGN, LOCATION AND SIZING OF THE CONCRETE WASHOUT AREA(S) WITH THE PROJECTS'S EROSION AND SEDIMENTATION CONTROL PLAN. 3. LOCATION: WASHOUT AREA(S) ARE TO BE LOCATED AT LEAST 50 FEET FROM ANY STREAM, WETLAND, STORM DRAINS, OR OTHER SENSITIVE RESOURCE. THE FLOOD CONTINGENCY PLAN MUST ADDRESS THE CONCRETE WASHOUT IF THE WASHOUT IS TO BE LOCATED WITHIN THE FLOODPLAIN. SIZE: THE WASHOUT MUST HAVE SUFFICIENT VOLUME TO CONTAIN ALL LIQUID AND CONCRETE WASTE GENERATED BY WASHOUT OPERATIONS INCLUDING, BUT NOT LIMITED TO, OPERATIONS ASSOCIATED WITH GROUT AND MORTAR. 4. SURFACE DISCHARGE IS UNACCEPTABLE. THEREFORE, STRAW BALES OR OTHER CONTROL MEASURES, SHOULD BE USED AROUND THE PERIMETER OF THE CONCRETE WASHOUT AREA FOR CONTAINMENT. 5. SIGNS SHOULD BE PLACED AT THE CONSTRUCTION ENTRANCE, AT THE CONCRETE AREA(S) AND ELSEWHERE AS NECESSARY TO CLEARLY INDICATE THE LOCATION OF THE CONCRETE WASHOUT TO OPERATORS OF CONCRETE TRUCKS AND PUMP RIGS. WASHOUT AREA(S) SHOULD BE FLAGGED WITH SAFETY FENCING OR OTHER APPROVED METHOD. 6. WASHOUT AREA(S) ARE TO BE INSPECTED AT LEAST ONCE A WEEK FOR STRUCTURAL INTEGRITY, ADEQUATE HOLDING CAPACITY AND CHECKED FOR LEAKS, TEARS OR OVERFLOWS. (AS REQUIRED BY THE CONSTRUCTION SITE ENVIRONMENTAL INSPECTION REPORT) WASHOUT AREA(S) SHOULD BE CHECKED AFTER HEAVY RAINS. 7. HARDENED CONCRETE WASTE SHOULD BE REMOVED AND DISPOSED OF WHEN THE WASTE HAS ACCUMULATED TO HALF OF THE CONCRETE WASHOUT'S HEIGHT. THE WASTE CAN BE STORED AT AN UPLAND LOCATION. ALL CONCRETE WASTE SHALL BE DISPOSED OF IN A MANNER CONSISTENT WITH ALL APPLICABLE LAWS, REGULATIONS, AND GUIDELINES. STRAW BALES OR COMPACTED EARTH BERM (SEE NOTE 3) VARIES SEE NOTE 2 SIDE SLOPES (SEE BELOW) DEPTH VARIES SEE NOTE 2 10 MIL POLYETHYLENE SHEETING SAND BAGS TO SECURE SHEETING (OR METHOD AS DIRECTED BY ENGINEER) SIDE SLOPES TO BE 2:1 OR 3:1 (NOMINAL) A15 A-14A-15 CONCRETE WASH OUT ROAD TRENCH (DUCT BANK) SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Road Treanch - 6-Way Ductbank.dwgDec 15, 2021-3:26pm Plotted By: ASapelli12/2021 NO SCALE30" MIN.FINISHED GRADE EQUALDUCTBANK MARKING TAPE (TYP) #4 REBAR (TYP) 112" MIN (TYP)" 3" MIN SEPARATION (TYP)EQUAL#4 REBAR (TYP) 18" OC 3" MIN (TYP) 3" MIN (TYP) BASE AND INTERMEDIATE SPACERS 48" OC EBR PVC (TYP) 4500 psi CONCRETE NOTES: 1. GEOTECH TEST, IN ACCORD WITH ASTM D608, THE BOTTOM OF EXCAVATION TO ACHIEVE 85% OF MAXIMUM DRY DENSITY, PRIOR TO CONCRETE PLACEMENT. A16 A-15A-16 ROAD TRENCH - DUCT BANK SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Road Treanch - Duct Bank.dwgDec 15, 2021-3:27pm Plotted By: ASapelli12/2021 NO SCALE A17 A-16A-17 ROAD TRENCH (6-WAY DUCT BANK) TREE PROTECTION SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Tree Prot.dwgDec 15, 2021-3:29pm Plotted By: ASapelli12/2021 NO SCALE PROTECTED ROOT ZONE NO STORAGE OF EQUIPMENT OR STOCKPILING OF MATERIALS WITHIN DRIPLINE EXISTING GRADE 2"X4" DIMENSIONAL LUMBER ATTACHED WITH METAL STRAPPING (OPTIONAL) AT TWO LOCATIONS (MINIMUM), DO NOT DAMAGE BARK, 6" SPACING OF BOARDS, CUT BOARDS TO FIT EXISTING ROOT SYSTEM (APPROXIMATE) PRUNE PER ISA STANDARDS REMOVE DEAD WOOD AND DAMAGED BRANCHES TIE UP BRANCHES IF RISK OF DAMAGE FROM CONSTRUCTION EQUIPMENT PRUNE ANY ROOTS EXPOSED AND/OR DAMAGED BY EXCAVATION WITH A SHARP SAW A18 A-17A-18 SOIL STOCKPILE MANAGEMENT SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Soil_Stpl_Mgmt.dwgDec 15, 2021-3:27pm Plotted By: ASapelli12/2021 NO SCALE ELEVATION VIEW PLAN VIEW STRAW BALES AND/OR SILT FENCE CONTAMINATED SOILS MUST BE ON AND COVERED WITH POLYETHYLENE SHEETING TO LIMIT EROSION. SHEETING NOT REQUIRED FOR NON-CONTAMINATED SOILS IF SEDIMENTATION AND EROSION CONTROLS COMPLETELY ENCLOSE STOCKPILE. STRAW BALES AND/OR SILT FENCE CONTAMINATED SOILS MUST BE ON AND COVERED WITH POLYETHYLENE SHEETING TO LIMIT EROSION. SHEETING NOT REQUIRED FOR NON-CONTAMINATED SOILS IF SEDIMENTATION AND EROSION CONTROLS COMPLETELY ENCLOSE STOCKPILE. SOIL SANDBAGS AS REQUIRED TO SECURE SHEETING POLYETHELENE SHEETING SANDBAG EACH BALE IN PAVED AREAS (TYP) BALES TO BUTT TOGETHER AA NOTE: 1. SANDBAGS (OR SIMILAR) MAY BE USED TO SECURE POLYETHYLENE SHEETING ON TOP OF THE STOCKPILE. 2. STRAW PRODUCTS ONLY; THE USE OF HAY OR HAY PRODUCTS IS STRICTLY PROHIBITED. SECTION A-A 2 STAKES EACH BALE IN UNPAVED AREAS (TYP) SOIL STOCKPILE STRAW BALE A19 A-18A-19 TOPSOIL SEGREGATION SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Topsoil.dwgDec 15, 2021-3:29pm Plotted By: ASapelli12/2021 NO SCALE NOTES: 1. TOPSOIL SEGREGATION TO BE USED IN WETLANDS AND AGRICULTURAL LAND. 2. IF WORKING WITHIN WETLANDS, MATTING BENEATH STOCKPILES MUST BE LINED OR UNDERLAIN BY GEOTEXTILE FABRIC. 3. STOCKPILES SHOULD BE ENCLOSED BY STRAW BALES OR WATTLES. WETLAND TRENCH TIMBER MAT STRAW BALE OR WATTLE A20 A-19A-20 STRAW BALE BARRIER SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Straw Bales.dwgDec 15, 2021-3:28pm Plotted By: ASapelli12/2021 NO SCALE DETAIL B RUNOFF SECTION A-A WORK ZONE PLAN FLOWWORK ZONE FLOWDETAIL A A A 6" MIN. FABRIC 6" MIN.FABRIC2"(TYP)18"4'-6"2"x2" WOOD STAKES SPACED AT 4'-5'± OC SILT FENCE GRADE SEE DETAIL B SILT FENCE SUITABLE BACKFILL SILT FENCE WOOD POSTS @4'-5'± O.C. FINISHED GRADE BUTT BALES TOGETHER SILT FENCE SEE DETAIL A (2) 2"x2"x3' STAKES AT EACH BALE EXISTING GROUND (2) 2"x2"x3' STAKES AT EACH BALE NOTE: USE OF HAY AND/OR PRODUCTS CONTAINING WEED SEED IS PROHIBITED. A21 A-20A-21 SILT FENCE SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Silt Fence.dwgDec 15, 2021-3:27pm Plotted By: ASapelli12/2021 NO SCALE 6" MIN.FABRIC6" MIN. FABRIC A A 18"4'-6"DETAIL AFLOWWORK ZONE FLOWPLAN WORK ZONE SECTION A-A RUNOFF DETAIL B SILT FENCE SEE DETAIL A 2"x2" WOOD STAKES SPACED AT 4'-5'± O.C. SILT FENCE GRADE SEE DETAIL B EXISTING GROUND SILT FENCE SUITABLE BACKFILL FINISHED GRADE A22 A-21A-22 SYNCOPATED SILT FENCE SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Syncopated Silt Fence.dwgDec 15, 2021-3:29pm Plotted By: ASapelli12/2021 NO SCALE SECTION A-A DETAIL A DETAIL B PLAN A A WORK ZONE WORK ZONE EXISTING GROUND 4'-6"18"FLOWFLOW2' GAP 2"X2" WOOD STAKES SPACED @ 4'-5'± O.C. FINISHED GRADE SILT FENCE SILT FENCE RUNOFF SEE DETAIL B SUITABLE BACKFILL 6" MIN. FABRIC 6" MIN. FABRIC 50' LENGTH SILT FENCE50' LENGTH SILT FENCE 20' LENGTH SILT FENCE 1'GAPA23 A-22A-23 REINFORCED SILT FENCE SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Silt Fence-Wire.dwgDec 15, 2021-3:27pm Plotted By: ASapelli12/2021 NO SCALE24"SECTION ELEVATION RUNOFF FILTRATION GEOTEXTILE GRADE A24 24" MAX18" MIN6'-0" MAX WITH WIRE TOP AND BOTTOM STRAND SHALL BE 10 GAUGE MIN. WIRE FILTRATION GEOTEXTILE MIDDLE AND VERTICAL WIRES SHALL BE 1212" GAUGE MIN. 4"8"STEEL POST COMPACTED FILL NOTES: 1. USE FILTRATION GEOTEXTILE A MINIMUM OF 36" IN WIDTH AND FASTEN ADEQUATELY TO THE POSTS AND WIRES AS DIRECTED. 2. USE A WIRE A MINIMUM OF 32" IN WIDTH AND WITH A MINIMUM OF 6 LINE WIRES WITH 12" STAY SPACING. 3. PROVIDE 5'-0" STEEL POST OF THE SELF-FASTENER ANGLE STEEL TYPE. 4. FOR MECHANICAL SLICING METHOD INSTALLATION, GEOTEXTILE SHALL BE A MAXIMUM OF 18" ABOVE GROUND SURFACE. 5. EXTEND GEOTEXTILE AND WIRE INTO TRENCH. A-23A-24 NOTES: 1. EROSION CONTROL BLANKET SHOULD BE INSTALLED VERTICALLY DOWNSLOPE. 2. STAKES/STAPLES SHOULD BE PLACED NO MORE THAN 3 FT. APART VERTICALLY, AND 1 FT. APART HORIZONTALLY. 3. SLOPE SURFACE SHOULD BE FREE OF STICKS, ROCKS, AND OTHER OBSTRUCTIONS. 4. BLANKETS SHOULD BE ROLLED OUT LOOSELY AND STAKED/STAPLED TO MAINTAIN DIRECT SOIL CONTACT. DO NOT STRETCH THE BLANKETS. 5. USE OF PRODUCTS WITH PLASTIC AND/OR NYLON NETTING IS PROHIBITED.MAXIMUM SLOPE=30%6"4' ≤ 1 ' 2- 3 " EROSION CONTROL BLANKET SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\E-Blanket.dwgDec 15, 2021-3:25pm Plotted By: ASapelli12/2021 NO SCALE SOIL SHOULD BE TAMPED DOWN OVER BLANKET STAKE/STAPLE (TYP) STAKE/STAPLE≤ 3'A25 A-24A-25 EROSION CONTROL BLANKETS STRAW WATTLE/MULCH LOG SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Straw Wattle2.dwgDec 15, 2021-3:28pm Plotted By: ASapelli12/2021 NO SCALE PLAN SECTION WORK ZONE FLOW WORK ZONE STAKE EVERY 10'± STRAW WATTLES OR MULCH LOGS WOODEN STAKE 3"-4"12"NOTE: 1. USE OF PRODUCTS WITH PLASTIC AND/OR NYLON NETTING IS PROHIBITED. AREA TO BE PROTECTED AREA TO BE PROTECTED A26 A-26 STRAW WATTLE (ON SLOPE) SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Straw Wattle.dwgDec 15, 2021-3:28pm Plotted By: ASapelli12/2021 NO SCALE ELEVATION VIEW SHALLOW DITCH PREPARED FOR STRAW WATTLE INSTALLATION STRAW WATTLE WOODEN STAKE FOOT TAMPED BACKFILL ON UPSLOPE SIDE 1. USE OF PRODUCTS WITH PLASTIC AND/OR NYLON NETTING IS PROHIBITED. 2. VERTICAL SPACING FOR SLOPE INSTALLATIONS TO BE DETERMINED BY SITE CONDITIONS: SLOPE GRADIENT AND SOIL TYPE. CONFIRM SPACING PER MANUFACTURER'S SPECIFICATIONS. SEE BELOW FOR TYPICAL REQUIREMENTS. COORDINATE SPACING AND LOCATION WITH EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING. ·1:1 SLOPES = 10 FEET APART ·2:1 SLOPES = 20 FEET APART ·3:1 SLOPES = 30 FEET APART 3. MINIMUM 12" DIAMETER WATTLES SHOULD BE USED FOR HIGHLY DISTURBED AREAS (E.G. HEAVILY USED ACCESS ROADS WITH ADJACENT WETLANDS). MINIMUM 8" DIAMETER WATTLES SHOULD BE USED FOR LESS DISTURBED SOILS. NOTES: STRAW WATTLE WOODEN STAKE A2 A-26A-27 A27 COMPOST FILTER TUBE SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Compost Filter Tube.dwgDec 15, 2021-3:22pm Plotted By: ASapelli12/2021 NO SCALE PLAN SECTION WORK ZONE FLOW WORK ZONE STAKE EVERY 10'± COMPOST FILTER TUBE 1"x1" WOODEN STAKE 3"-4"12"NOTES: 1. TUBES FOR COMPOST FILTERS SHALL BE JUTE MESH OR APPROVED BIODEGRADABLE MATERIAL. 2. TAMP TUBES IN PLACE TO ENSURE GOOD CONTACT WITH SOIL SURFACE. 3. PROVIDE 3' MINIMUM OVERLAP AT ENDS OF TUBES TO JOIN IN A CONTINUOUS BARRIER AND MINIMIZE UNIMPEDED FLOW. 4. COMPOST MATERIAL SHALL BE DISPERSED ON SITE WITHIN LIMITS OF WORK, AS DIRECTED. 5. INSTALL TUBES ALONG CONTOURS AND PERPENDICULAR TO SHEET OR CONCENTRATED FLOW. 6. DO NOT INSTALL IN PERENNIAL, EPHEMERAL, OR INTERMITTENT STREAMS. 7. CONFIGURE TUBES AROUND EXISTING SITE FEATURES TO MINIMIZE SITE DISTURBANCE AND MAXIMIZE CAPTURE AREA OF STORMWATER RUN-OFF. COMPOST FILTER TUBE 12"-18" DIA. (TYP)AREA TO BE PROTECTED AREA TO BE PROTECTED A28 A-27A-28 TURBIDITY CURTAIN SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Turbidity Curtain.dwgDec 15, 2021-3:29pm Plotted By: ASapelli12/2021 NO SCALE A A BAFFLE ELEVATION DIELECTRIC SEAM BOTTOM HEM 1 4" Ø HDG STEEL PROOF-COIL CHAIN 516" Ø ANCHOR CONNECT QUICK-LINK 3 8" Ø POLYPROPYLENE ANCHOR LIFTING LINE DIELECTRIC SEAM BAFFLE SKIRT 8OZ. NONWOVEN GEOTEXTILE UNICELLULAR POLYSTYRENE FOAM FLOATATION 20' TYP VERIFY IN FIELD 10' TYP VERIFY IN FIELD6"ØNOTES: 1. TURBIDITY CURTAIN BY ENVIRONETICS, INC. OR APPROVED EQUAL. 2. TURBIDITY CURTAIN SHALL NOT BE EXTENDED ACROSS CHANNEL FLOWS. 3. TURBIDITY CURTAIN MATERIAL SHALL BE ULTRAVIOLET LIGHT RESISTANT. TYPE I II III IV DESCRIPTION FLATWATER LIGHTWEIGHT MIDDLEWEIGHT HEAVYWEIGHT CONDITIONS CALM AND PROTECTED SEMI-PROTECTED AREA, CURRENTS UP TO 2 FT/S EXPOSED AREA, CURRENTS UP TO 5 FT/S EXPOSED TO WIND, CURRENT, AND TIDES GAP (IN.) 0 12 12 0 GAP, SEE TABLE SECTION A-A A29 A-28A-29 CATCH BASIN INLET PROTECTION (STRAW BALES) SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\CB Inlet Prot.dwgDec 15, 2021-3:21pm Plotted By: ASapelli12/2021 NO SCALE GUTTER LINE GUTTER LINE PLAN ELEVATION NOTES: 1. A MINIMUM OF TWO WOOD STAKES ARE REQUIRED PER STRAW BALE. 2. STEEL DOWELS MAY BE USED WHERE WOOD STAKES CANNOT BE DRIVEN INTO THE GROUND. 3. "SILT SACKS", "DANDY BAG II" OR OTHER SIMILAR SILT RETENTION DEVICES SHALL BE INSTALLED IN LIEU OF STRAW BALES FOR CATCH BASINS LOCATED IN EXISTING PAVED AREAS. 4. STRAW PRODUCTS ONLY; THE USE OF HAY OR HAY PRODUCTS IS STRICTLY PROHIBITED. 2" X 2" X 3' STAKES OR STEEL DOWELS (TYP) 2" X 2" X 3' STAKES OR STEEL DOWELS (TYP) STRAW BALE CATCH BASIN FRAME AND COVER EXISTING GRADE A30 A-29A-30 CATCH BASIN INLET PROTECTION (SILT SACK) SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Silt Sack.dwgDec 15, 2021-3:27pm Plotted By: ASapelli12/2021 NO SCALE PLAN VIEW NOTES: 1. FILTER BASKET SHALL BE "SILT SAK" BY JENNIAN, MELROSE, MA; "DANDY BAG" BY DANDY PRODUCTS (1-800-591-2284); DRAIN PAC (91-800-272-2832); OR APPROVED EQUIVALENT SUBJECT TO CONSULTATION WITH EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING. 2. FILTER BASKETS SHOULD BE USED IN COMBINATION WITH ANOTHER INLET PROTECTION MEASURE SUCH AS SEDIMENT FILTER FABRIC IF DRAINAGE AREA IS SMALL WITH SHALLOW FLOWS. ELEVATION VIEW FINISH GRADE GUTTER LINEGUTTER LINE SEDIMENT FILTER FABRICCATCH BASIN FRAME & COVER FILTER BASKET SEDIMENT FILTER FABRIC A31 A-30A-31 LOAM AND SEED SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Loam and Seed.dwgDec 15, 2021-3:26pm Plotted By: ASapelli12/2021 NO SCALE SEED MIX FOR LAWNS: TALL FESCUE - 70% KENTUCKY BLUEGRASS - 10% PERENNIAL RYEGRASS - 20% APPLY AT 2LBS PER 1000 S.F. FINISH GRADE 3" MINIMUM TOPSOIL SUB-GRADE NOTE: THE SEED MIX UTILIZED SHALL CONSIST OF QUICK GROWING, DROUGHT TOLERANT, NATIVE GRASSES, SUCH AS RYES. THE SEED MIX UTILIZED WITHIN THE BUFFER ZONE TO WETLAND RESOURCE AREAS MAY CONSIST OF QUICK GROWING, DROUGHT TOLERANT, NATIVE GRASSES BUT MUST CONTAIN AT LEAST 50% OF A NATIVE SEED MIX WITH HIGH HABITAT VALUE, SUCH AS ONES WHICH CONTAIN PERENNIAL SHRUBS, WILDFLOWERS. CONSULT WITH EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING FOR PROJECT SPECIFIC REQUIREMENTS. A32 A-31A-32 STRAW MULCH SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Straw Mulch.dwgDec 15, 2021-3:28pm Plotted By: ASapelli12/2021 NO SCALE STRAW MULCH: 1" THICK MAX UNSTABLE SOILS NOTES: 1. STRAW PRODUCTS ONLY; THE USE OF HAY OR HAY PRODUCTS IS STRICTLY PROHIBITED. 2. MULCH APPLICATION SHALL NOT EXCEED 1" IN THICKNESS. 3. WOOD CHIPS MAY BE SUBSTITUTED FOR STRAW MULCH SUBJECT TO EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING APPROVAL. 4. CONSULT WITH EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING FOR PROJECT SPECIFIC REQUIREMENTS. A33 PLAN VIEW ELEVATION VIEW LIMIT OF SOIL DISTURBANCESTRAW MULCH A-32A-33 COIR LOG SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Coir log.dwgDec 15, 2021-3:22pm Plotted By: ASapelli12/2021 NO SCALE STREAM BED COIR LOG AND EROSION CONTROL SEED MIX TOP OF BANK/OHW WOODEN STAKES (2 FT. LONG) NORMAL WATER LEVEL NOTES: 1. USE OF PRODUCTS WITH PLASTIC AND/OR NYLON NETTING IS PROHIBITED. 2. INSTALL PER MANUFACTURER'S RECOMMENDATIONS. 3. INSTALLATION MAY INCLUDE SEEDING AND/OR OTHER NATIVE PLANT INSTALLATION. CONSULT EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING. TYPICAL STAKING UPLAND 3' 3' A34 A-33A-34 LEVEL SPREADER SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Level Spreader.dwgDec 15, 2021-3:26pm Plotted By: ASapelli12/2021 NO SCALE SECTION A-A PLAN VIEW 3 1 3 1 4' WIDTH 12" MIN. NOTE: WHERE GROUND DOWNSTREAM OF LEVEL SPREADER HAS BEEN DISTURBED, VEGETATIVE COVER SHALL BE ESTABLISHED. FILTER FABRIC 3/4" CRUSHED STONE 2" CRUSHED STONE EXISTING GROUND 4" LOAM AND SEED COVER CREST WITH EROSION CONTROL BLANKET LEVEL SPREADER LEVEL SPREADER MEET EXISTING GRADE4'A A A35 A-34A-35 CHECK DAMS SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Check Dams.dwgDec 15, 2021-3:22pm Plotted By: ASapelli12/2021 NO SCALE A36 SWALE ELEVATION VIEW STRAW BALE CHECK DAM ACCESS ROAD SURFACE STABLE UPLANDS ACCESS ROAD PLAN VIEW CHECK DAM (SEE BELOW)SWALE EROSION CONTROL BLANKETS (OPTIONAL) STRAW BALE CHECK DAM SWALE ELEVATION VIEW STONE CHECK DAM ACCESS ROAD SURFACE EROSION CONTROL BLANKETS (OPTIONAL) STONE CHECK DAM NOTES: 1. CHECK DAMS SHALL BE CONSTRUCTED OF STONE OR STRAW PRODUCTS ONLY; THE USE OF HAY OR HAY PRODUCTS IS STRICTLY PROHIBITED. 2. HEIGHT AND SPACING OF CHECK DAMS IS DEPENDENT ON SLOPES AND RUNOFF CONDITIONS. CONSULT WITH EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING PRIOR TO INSTALLATION FOR PROJECT SPECIFIC REQUIREMENTS. 3. REMOVE TEMPORARY CHECK DAMS UPON SWALE STABILIZATION AND/OR COMPLETION OF CONSTRUCTION. A-35A-36 TRENCH BREAKER SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Trench Breaker.dwgDec 15, 2021-3:29pm Plotted By: ASapelli12/2021 NO SCALE BOTTOM OF DITCH SECTION ELEVATION GRADED RIGHT-OF-WAY GRADED RIGHT-OF-WAY SANDBAGS COMPACTED FILL PIPELINE CROSS-COUNTRY BURIED PIPELINE BOTTOM OF DITCH SECTION ELEVATION EXISTING ROAD EXISTING ROAD SANDBAGS COMPACTED FILL PIPELINE IN-ROAD BURIED PIPELINE A37 A-36A-37 SEDIMENT TRAP SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\E-Sediment Trap.dwgDec 15, 2021-3:25pm Plotted By: ASapelli12/2021 NO SCALE GROUND SLOPE 2' HIGH CLEAN STONES (d =6") GROUND SLOPE STRAW BALE SECTION A-A AA 2' 15'-20' (TYP) OR AS DIRECTED SEDIMENT FREE WATER 10'-15' (TYP) OR AS DIRECTED 50 PUMP DISCHARGE LINE FILTER BAG FLAT STONE FILTER FABRIC MAT SEDIMENT STRAW BALE FILTER FABRIC MAT PUMP DISCHARGE SEDIMENT LADEN WATER FILTER BAG. CAPACITY OF FILTER BAG SHALL BE ADEQUATE TO HANDLE DEWATERING PUMP DISCHARGE. TO NATURAL WATER COURSE NOTES: 1. LOCATION OF SEDIMENT TRAP SUBJECT TO CONSULTATION WITH EVERSOURCE ENVIRONMENTAL LICENSING AND PERMITTING. 2. SEDIMENT TRAPS OR SETTLING BASINS SHALL BE USED FOR CONSTRUCTION DEWATERING. 3. DISCHARGE AWAY FROM WORK AREA/DEWATERING AREA. A38 A-37A-38 DEWATERING BASIN SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Dewat_Basin1.dwgDec 15, 2021-3:24pm Plotted By: ASapelli12/2021 NO SCALE PERSPECTIVE PLAN VIEW SECTION FILTER FABRIC MAT LINING ON BOTTOM AND SIDES PUMP DISCHARGE HOSE STRAW BALES EMBEDDED 4" AND STAKED AS REQUIRED PUMP DISCHARGE HOSE STRAW BALES EMBEDDED 4" AND STAKED AS REQUIRED PUMP DISCHARGE HOSE STRAW BALES EMBEDDED 4" AND STAKED AS REQUIRED SET 2 STRAW BALES 2" BELOW ADJOINING FILTER FABRIC MAT LINING ON BOTTOM AND SIDES NOTE: PLACE DEWATERING/PUMPING SETTLING BASINS IN A WELL-VEGETATED AREA, OUTSIDE OF WETLANDS WHENEVER PRACTICABLE. A39 A-38A-39 DEWATERING FILTER BAG SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Dewat_Basin2.dwgDec 15, 2021-3:24pm Plotted By: ASapelli12/2021 NO SCALE PERSPECTIVE HOSE INLET STRAW BALES SECTION PLAN DISCHARGE HOSE ONE PER FILTER BAG HOSE CLAMP FILTER BAG SET ON FILTER FABRIC 15'STAKES MAXFILTER BAG FILTER BAG NOTE: PLACE FILTER BASINS IN A WELL-VEGETATED AREA, OUTSIDE OF WETLANDS WHENEVER PRACTICABLE.16'4'2 STAKES PER BALE (TYP ALL BALES) A40 A-39A-40 DEWATERING BASIN (FILTER BAG) DEWATERING (FRAC TANK) SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Frac Tank.dwgDec 15, 2021-3:25pm Plotted By: ASapelli12/2021 NO SCALE CONTINGENCY TREATMENT FOR REGULATED GROUNDWATER PROCESS A41 A-40A-41 DEWATERING BASIN (FRAC TANK) COFFER DAM AND STREAM FLOW BYPASS (GRAVITY) SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Coffer Dam Gravity.dwgDec 15, 2021-3:22pm Plotted By: ASapelli12/2021 NO SCALE FLOW FLOW DRY WORK AREA PLAN VIEW - GRAVITY COFFER DAM BYPASS HOSE TEMPORARY COFFER DAM (SANDBAGS OR SIMILAR) A42 A-42 COFFER DAM AND STREAM FLOW BYPASS (PUMPING) SCALE: DATE: FIGURE:Tighe & Bond, Inc. F:\Projects\E\E5034 Eversource L&P 2019\088 - CT-MA BMP Manual\Drawings_Figures\AutoCAD\Sheet\Coffer Dam.dwgDec 15, 2021-3:22pm Plotted By: ASapelli12/2021 NO SCALE FLOW FLOW DRY WORK AREA PLAN VIEW - PUMP COFFER DAM DISCHARGE HOSE PUMP TEMPORARY COFFER DAM (SANDBAGS OR SIMILAR) TEMPORARY SPLASH PAD TO SLOW VELOCITY A43 A-41A-43 APPENDIX B Table of Contents B-i APPENDIX B Appendix B B.1 Applicable Laws/Regulations ............................................................B- 1 B.2 Geographic Areas Subject to Jurisdiction ...........................................B- 1 B.3 Applicable Regulatory Agencies ........................................................B- 2 B.4 Maintenance, Repair, or Emergency Projects .....................................B- 3 B.4.1 Maintain, Repair and/or Replace .............................................B- 3 B.4.2 Emergency Projects ..............................................................B- 3 B.5 Municipal Permitting .......................................................................B- 4 B.6 CT Department of Energy & Environmental Protection .........................B- 4 B.7 U.S. Army Corps of Engineers ..........................................................B- 5 B.8 Culvert Installation .........................................................................B- 8 B.8.1 Municipal Permitting .............................................................B- 8 B.8.2 CT Department of Energy & Environmental Protection ...............B- 9 B.8.3 U.S. Army Corps of Engineers ................................................B- 9 Tighe&Bond Eversource Best Management Practices Manual –January 2022 B-1 Appendix B B.1 Applicable Laws/Regulations In Connecticut, there are no fewer than eight potentially pertinent regulatory programs associated with activities proposed in environmentally sensitive areas. The fol lowing list of laws and regulations are most likely to apply to electrical utility projects in the State. • Connecticut Inland Wetlands and Watercourses Act (C.G.S. §§ 22a-36 through 22a- 45a) • Municipal inland wetland and zoning regulations • Connecticut General Permit for Water Resource Construction Activities (C.G.S. §§ 22a-6, 22a-45a and 22a-378a) • Connecticut Environmental Policy Act (C.G.S. §§ 22a-1a through 22a-1h) • Connecticut Coastal Management Act (C.G.S. §§ 22a-359 through 22a-363; 22a-28 through 22a-35; 22a-90 through 22a-112; 33 U.S.C. § 1314) • Connecticut Water Diversion Policy Act (C.G.S. §§ 22a-365 through 22a-379) • Connecticut Endangered Species Act (C.G.S. §§ 26-303 through 26-315) • Section 10 of the Rivers and Harbors Act of 1899 (C.G.S. §§ 22a-426; 33 U.S.C. § 403) • Section 401 of the Clean Water Act (33 U.S.C. § 1251) • Section 404 of the Clean Water Act (33 U.S.C. § 1344) B.2 Geographic Areas Subject to Jurisdiction The following areas are subject to regulatory jurisdiction by at least one of the regulatory programs discussed in this section: It is important to note that more than one jurisdictional resource type may be present at any given location. • Inland wetlands, watercourses (rivers, streams, lake s, ponds), and floodplains • Areas subject to municipal wetlands bylaws or ordinances (these vary by town) • Coastal Resource Areas (beaches, dunes, bluffs, escarpments, coastal hazard areas, coastal waters, nearshore waters, offshore waters, estuarine embayments, developed shorefront, intertidal flats, islands, rocky shorefronts, shellfish concentration areas, shorelands, and tidal wetlands) • Navigable waters • Essential Fish Habitat (EFH) • Rare species habitat as mapped by the Connecticut Natural Diversity Database (NDDB) • Historic/cultural Resources including archaeological resources and above -ground historic resources Eversource Best Management Practices Manual –January 2022 Appendix B B-2 B.3 Applicable Regulatory Agencies Activities subject to jurisdiction under the above-referenced programs will generally be subject to review by one or more regulatory agencies (refer to list below). Most stream and wetland crossings will require notification or consultation with municipal Inland Wetland and Watercourses Agencies, and may require permitting with the U.S. Army Corps of Engineers (ACOE) and Connecticut Department of Energy & Environmental Protection (CT DEEP) u nder Sections 404 and 401 of the Clean Water Act. Coordination with CT DEEP may also be required for projects located within areas mapped by the Connecticut Natural Diversity Database. • Municipal Conservation Commissions • Connecticut Department of Energy & Environmental Protection (CT DEEP) Land and Water Resources Division (LWRD) • CT DEEP Wildlife Division • CT DEEP Office of Environmental Review • United States Army Corps of Engineers (ACOE) New England District • CT State Historic Preservation Office (CT SHPO) The State of Connecticut and the Federal Government define wetlands differently. According to the Inland Wetlands and Watercourses Act, inland wetlands are defined as “land, including submerged land, not regulated pursuant to Sections 22a-28 through 22a- 35 of the Connecticut General Statutes, as amended, which consists of any of the soil types designated as poorly drained, very poorly drained, alluvial, and floodplain by the National Cooperative Soil Survey, as it may be amended from time to time by the United States Department of Agriculture Natural Resource Conservation Service. Such areas may include filled, graded, or excavated sites which possess an aquic (saturated) soil moisture regime as defined by the National Cooperative Soil Survey.” State wetland identification is based solely on the presence of these soil types. “Watercourses" means rivers, streams, brooks, waterways, lakes, ponds, marshes, swamps, bogs and all other bodies of water, natural or artificial, vernal or intermittent, public or private, which are contained within, flow through or border upon this state or any portion thereof. Intermittent watercourses shall be delineated by a defined permanent channel and bank and the occurrence of two or more of the following characteristics: (A) Evidence of scour or deposits of recent alluvium or detritus, (B) the presence of standing or flowing water for a duration longer than a particular storm incident, and (C) the presence of hydrophytic vegetation. The Federal Government defines wetlands as “Those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetatio n typically adapted for life in saturated soil conditions.” Federal wetland identification is based on a three- parameter approach, where a prevalence of hydrophytic vegetation, hydric soils, and wetland hydrology is used to make a wetland determination. Eversource Best Management Practices Manual –January 2022 Appendix B B-3 B.4 Maintenance, Repair, or Emergency Projects Most regulatory programs contain provisions that allow normal maintenance of existing structures and/or response to emergency situations that require immediate attention. Prior to commencement of new construction, all jurisdictional wetland areas within the work corridor should be delineated by a qualified wetland and soil scientist. The specialist shall delineate areas in accordance with the General Statutes of Connecticut (revised January 1, 2007) as set forth at Title 22a Chapter 440 “Inland Wetlands and Watercourses Act”, the U.S. Army Corps of Engineers 1987 Wetland Delineation Manual, and any local inland wetland regulations, ordinances or bylaws that may ex ist. Refer to each set of regulations regarding applicable wetland definitions. Wetland areas shall be clearly demarcated using appropriate flagging tape or similar means. It is important to note that certain jurisdictional wetland areas in Connecticut can actually occur in uplands, such as floodplains. In addition, Upland Review Areas generally apply to work activities and vary in each community. This makes consultation with a wetland specialist particularly important. B.4.1 Maintain, Repair and/or Replace Exemptions or considerations for maintenance, repair, and/or replacement of existing electrical utility structures exist in some environmental regulations, but not all. The exemptions are limited to work related to existing and lawfully located structures where no change in the original structure or footprint is proposed. It is not for the selected contractor of a particular project to make a determination as to whether an activity is exempt. This determination will be made prior to work by the Eversource project manager, in consultation with Eversource environmental staff. These exemptions/considerations are afforded at: • CT Inland Wetlands & Watercourses Act (RCSA § 22a-39-4) • CT General Permit (Section 3) • CT Coastal Management Act (RCSA § 22a-363b) • CT GP [33 CFR 323.4(a)(2)] • CT Water Diversion Policy Act (RCSA § 22a-377(b)1) B.4.2 Emergency Projects Emergency provisions are generally afforded to activities that need to abate conditions that pose a threat to public health or safety. These provisions generally do not allow work beyond what is necessary to abate the emergency condition and will generally require an after-the-fact permit. It is not for the selected contractor of a particular project to make a determination as to whether an activity is an emergency. This determination will be made prior to work by the Eversource project manager, in consulta tion with Eversource Environmental Licensing and Permitting. It is important to note that invocation of an emergency provision does not release the project proponent from reporting requirements. Emergency provisions are afforded at: • CEPA (RCSA § 22a-1a-3) • CT Coastal Management Act (RCSA § 22a-29) • CT GP [33 CFR Part 323.4(a)(2)] Eversource Best Management Practices Manual –January 2022 Appendix B B-4 B.5 Municipal Permitting Work within wetlands, watercourses and designated Upland Review Areas typically requires notification to municipal staff, (Department of Public Works and/or the Inland Wetland and Watercourse Agency staff). In October 1996 the Connecticut Department of Public Utility Control opened a docket (Docket Number 95 -08-34) to conduct a generic investigation on the allocation of siting jurisdiction over utility plant facil ities. This included an investigation as to whether local authorities (including local Inland Wetlands and Watercourses Agencies) have jurisdiction over public utility projects. The investigation resulted in several orders which provide guidance on how pub lic utility companies should coordinate with municipalities on the construction of new facilities, upgrades, significant maintenance activities, and routine maintenance activities. • For the construction of new facilities, alterations to existing facilities (including upgrades) or significant maintenance involving substantial disturbance of soil, water or vegetation which would regularly fall under the review requirements of certain local authorities (ie. Planning and Zoning Authority; Inland Wetlands Commission; Public Works Department; Historic District Commission), the utility shall at least notify and consult with such local authority, or its designated agent or staff, toward the development of mutually agreeable schedules and procedures for the proposed activity. • For routine maintenance activities or alterations to existing facilities (including upgrades) involving minor disturbance of soil, water or vegetation which would regularly fall under the review and approval requirements of certain local authorities, the utility shall make local authorities or their designated agent or staff aware of such ongoing activities. B.6 CT Department of Energy & Environmental Protection If the project requires formal permitting with the ACOE (Pre-Construction Notification (PCN) or Individual Permit), copies of the application should be forwarded to CT DEEP for review under Section 401 of the Clean Water Act. The CT DEEP requires that a GP Addendum form be completed and submitted along with the ACOE application. If the project qualifies for Self-Verification Notification (SVNF) under the ACOE GP, the project also is granted authorization (Water Quality Certification, WQC) with no formal application under Section 401 of the Clean Water Act, provided the project meets the additional WQC general conditions. The general conditions commonly applicable to utility projects include: • Prohibiting dumping of any quantity of oil, chemicals, or other deleterious material on the ground; • Immediately informing the CT DEEP Oil and Chemical Spill Response Division at (860) 424-3338 (24 hours) of any adverse impact or hazard to the environment including any discharge or spillage of oil or chemical liquids or solids; • Separating staging areas at the site from the regulated area s by silt fences or stray/hay bales at all times; • Prohibiting storage of any fuel and refueling of equipment within 25 feet from any wetland or watercourse; • Following the document “Connecticut Guidelines for Soil and Erosion Control,” inspecting employed controls at least once per week, after each rainfall, and at least daily during prolonged rainfall, and correcting any deficiencies within 48 hours of being found. Eversource Best Management Practices Manual –January 2022 Appendix B B-5 • Prohibiting the storage of any materials at the site which are buoyant, hazardous, flammable, explosive, soluble, expansive, radioactive, or which could in the event of a flood be injurious to human, animal or plant life, below the elevation of the • 500 year flood. Any other material or equipment stored at the site below this elevation must be firmly anchored, restrained or enclosed to prevent flotation. The quantity of fuel for equipment at the site stored below such elevation shall not exceed the quantity of fuel that is expected to be used by such equipment in one day. • Immediately informing CT DEEP at (860) 424-3019 and the ACOE at (617) 647- 8674 of the occurrence of pollution or other environmental damage in violation of the WQC, and within 48 hours support a written report including information specified in the general conditions. If the project falls within areas mapped by the Connecticut Natural Diversity Database, or is less than 0.50 miles upstream or downstream of a mapped area, a data request and possible coordination will be required with the Natural Diversity Database. If a project is located within tidal, coastal or navigable waters of the state or in tidal wetlands, permitting may be required with the CT DEEP LWRD. For the routine maintenance of previously permitted structures or structures that were in place prior to June 24, 1939, no permitting is required. For significant maintenance of previously permitted structures or structures that were in place prior to June 24, 1939, a Certificate of Permission is required. For new projects a Structures, Dredging and Fill Permit and/or a Tidal Wetlands Permit may be required. The CT DEEP LWRD should be consulted prior to preparing permits to conduct a pre-application meeting and determine the appropriate permitting route. B.7 U.S. Army Corps of Engineers Work within wetlands and waters of the United States is subject to jurisdiction under Section 404 of the Clean Water Act, which is administered by the ACOE. Work within navigable waters is also administered by the ACOE under Section 10 of the Rivers and Harbors Act of 1899. The ACOE has issued Department of the Army General Permits for the State of Connecticut and Land Located within the Boundaries of an Indian Reservation (CT GPs) which establishes categories for projects based on their nature of impacts. The current permit was issued on December 15, 2021, and expires on December 15, 2026. Applications are not required for Self-Verification (SV) projects, but submittal of a Self- Verification Notification Form (SVNF) before the work occurs and submittal of a Compliance Certification Form within one month after the work is completed is required. The SVNF and Compliance Certification Form entail self-certification by applicants that their project complies with the terms and conditions of SV under the CT GPs. Pre- Construction Notification (PCN) projects require the submittal of an application to the ACOE, followed by a screening of the application by the ACOE, the U.S. Fish and Wildlife Service (USFWS), U.S. Environmental Protection Agency (US EPA), National Marine Fisheries Service (NMFS) and CT DEEP, and consultation with the Connecticut Commission on Culture and Tourism and Tribal Historic Preservation Officers (THPOs). PCN projects may not proceed until written approval from the ACOE is received. Written approval is generally provided within 45 days of the multi-agency screening. After written approval is received, a Work-Start Notification Form must be submitted before the work occurs, and a Compliance Certification Form must be submitted within one month after the work is completed. Eversource Best Management Practices Manual –January 2022 Appendix B B-6 For work proposed within a FEMA floodway or floodplain, the ACOE recommends that the applicant apply for and receive a Flood Management Certification (if required), prior to applying to the ACOE. Additionally, applications for PCN inland projects that propose fill in ACOE jurisdiction must include an Invasive Species Control Plan (ISCP), unless otherwise directed by the ACOE. An Individual Permit (IP) requires a formal permit application to be submitted to the ACOE. The application is reviewed in detail by both state and federal agencies, and a Public Notice is released for public comment. Projects which trigger an IP generally result in significant impacts to wetlands and/or watercourses. Stream and wetland crossings are only subject to jurisdiction under the ACOE if there is a discharge of dredge or fill material into wetlands or waters of the United States. Equipment access through a stream or wetland with no structural BMP is not regulated by the ACOE if there is no discharge of dredge or fill material (note that equipment rutting as a result of not using an appropriate BMP can be considered a “disch arge of dredge material”). Similarly, the use of a timber or rail car bridge that extends from bank to bank with no stream impacts is not regulated by the ACOE. Additionally, the use of timber mats and stone is considered “fill material” by the ACOE, and must be calculated to determine overall impacts. Temporary mats are not counted towards the 1-acre PCN threshold if they are adequately cleaned after previous use, removed immediately after completion of construction and disposed of at an upland site. Maintenance, including emergency reconstruction of currently serviceable structures, is exempt from ACOE jurisdiction and does not require formal permitting. Maintenance does not include any modification that changes the character, scope, or size of the origina l fill design. Emergency reconstruction must occur within a reasonable period of time after damage occurs to qualify for this exemption. Stream and wetland crossings that involve the discharge of dredge and fill material may be conducted under SV if the work complies with the general conditions and SV criteria of the CT GPs. The following are SV criteria that are commonly applicable to stream and wetland crossings in utility rights of way. See Section 1.8 for additional criteria for culvert crossings: • The work results in less than 5,000 square feet of impacts to wetlands or Waters of the United States. Replacement of utility line projects with impacts solely within wetlands greater than 5,000 square feet may be eligible for SV Authorization after consultation with the ACOE about the specific project; • Temporary fill, with the exceptions of swamp and timber mats, discharged to wetlands shall be placed on geotextile fabric laid on the pre-construction wetland grade. Unconfined temporary fill discharged into flowing water (rivers and streams) shall consist only of clean stone. All temporary fill shall be removed as soon as it is no longer needed, and disposed of at an appropriate upland site. • Any unconfined in-stream work, including construction, installation or removal of sheet pile cofferdam structures, is conducted during the low -flow period between July 1 and September 30. However, installation of coffer dams, other than sheet pile cofferdams, is not restricted to the low -flow period and must be installed between July 1 and March 31 and must not encroach > 25% of the stream width measured from OHW during the prohibited work window; • No work will occur in the main stem or tributary streams of the Connecticut River watershed that are being managed for Atlantic salmon (Salmo salar). (Work of this Eversource Best Management Practices Manual –January 2022 Appendix B B-7 nature requires screening for potential impacts to designated Essential Fish Habitat.); • The work does not result in direct or secondary impacts to Special Wetlands, Threatened, Endangered or Special Concern Species, or Significant Natural Communities identified by the Connecticut Natural Diversity Database. Work within 750 feet of vernal pools shall be minimized; • The project does not require an ACOE permit with associated construction activities within 100 feet of Special Wetlands; • The project does not result in fill placed within a FEMA established floodway, unless the applicant has a State of Connecticut Flood Management Certification pursuant to Section 25-68d of the Connecticut General Statutes; • The project does not result in fill placed within a FEMA established floodplain that would adversely affect the hydraulic characteristics of the floodplain; • The project does not entail stormwater detention or retention in inland waters or wetlands; • The project is not located in a segment of a National Wild and Scenic River System (includes rivers officially designated by Congress as active study status rivers for possible inclusion) or within 0.25 miles upstream or downstream of the main stem or tributaries to such a system; • The project has no potential for an effect on a historic property which is listed or eligible for listing in the National Register of Historic Places; • The project does not impinge upon the value of any National Wildlife Refuge, National Forest, or any other area administered by the U.S. Fish and Wildlife Service, U.S. Forest Service or National Park Service; • Section 106 needs to be taken into account for all work that requires federal permitting – including SV; • The project does not use slip lining, plastic pipes, or High Density Polyethylene Pipes (HDPP). • Appropriate BMPs are employed in regard to heavy equipment in wetlands (General Condition 16) and sedimentation and erosion controls (General Condition 20). • Disturbed inland wetland areas are restored in accordance with General Condition 18. Stream and wetland crossings that involve the discharge of dredge and fill material may be conducted under PCN if the work complies with the general conditions and PCN criteria of the CT GPs. The following are PCN criteria that are commonly applicable to stream and wetland crossings in utility ROWs. See Section 1.8 for additional criteria for culvert crossings: • The work results in less than one acre of impacts to wetlands or Waters of the United States; • The project does not result in fill placed within a FEMA established floodplain that would adversely affect the hydraulic characteristics of the floodplain; • The project does not entail stormwater detention or retention in inland waters or wetlands. • Temporary fill, with the exceptions of swamp and timber mats, discharged to Eversource Best Management Practices Manual –January 2022 Appendix B B-8 wetlands shall be placed on geotextile fabric laid on the pre-construction wetland grade. Unconfined temporary fill discharged into flowing water (rivers and streams) shall consist only of clean stone. All temporary fill shall be removed as soon as it is no longer needed, and disposed of at an appropriate upland site. • Appropriate BMPs are employed in regard to heavy equipment in wetlands (General Condition 16) and sedimentation and erosion controls (General Condition 20). • Disturbed inland wetland areas are restored in accordance with General Condition 18. Stream and wetland crossings that cannot meet SV or PCN criteria may require review under an IP. The ACOE should be consulted before assuming an IP will be required, as exceptions can be made under certain circumstances. GP1. Aids to navigation & temporary recreational structures (Coastal only) GP2. Repair or maintenance of existing currently serviceable, authorized or grandfathered structures/fills and removal of structures (Coastal and Inland) GP3. Moorings (Coastal only) GP4. Pile-supported structures & floats, including boat lifts/hoists & other miscellaneous structures & work (Coastal only) GP5. Boat ramps and marine railways (Coastal and Inland) GP6. Utilities including lines, outfall and intake structures and appurtenant structures (Coastal and Inland) GP7. Dredging, transport & disposal of dredged material, beach nourishment & rock removal and rock relocation (Coastal only) GP8. Discharges of dredged or fill material incidental to the co nstruction of bridges (Coastal only) GP9. New shoreline and bank stabilization projects and Living Shorelines (Coastal and Inland) GP10. Aquatic habitat restoration, establishment and enhancement activities (Coastal and Inland) GP11. Fish and wildlife harvesting activities (Coastal and Inland) GP12. Oil spill and hazardous material response operations (Coastal and Inland) GP13. Cleanup of hazardous and toxic waste and removal of contaminated soil (Coastal and Inland) GP14. Scientific measurement and monitoring devices (Coastal and Inland) GP15. Survey and exploratory survey activities (Coastal and Inland) GP16. Aquaculture & Mariculture Activities (Coastal only) GP17. New and expansion of recreational, residential, institutional, and commercial developments (Inland only) GP18. Wetland crossings for linear transportation projects (Inland only) GP19. Stream, river and brook crossings (not including wetland crossings) (Coastal and Inland) GP20. Energy generation and renewable energy generation facilities and hydropower projects (Coastal and Inland) GP21. Temporary fill not associated with a regulated General Permit activity (Inland only) GP22. Modification and Improvement of Existing Minor drainage features and Mosquito Control (Coastal only) GP23. Agricultural Activities (Inland only) Eversource Best Management Practices Manual –January 2022 Appendix B B-9 B.8 Culvert Installation New culvert installation or existing culvert replacements will require notification or consultation with municipal staffers which might include the Department of Public Works and/or the inland wetlands officer, and may require permitting with the ACOE under Section 404 of the Clean Water Act or Section 10 of the Rivers and Harbors Act of 1899, and the CT DEEP under Section 401 of the Clean Water Act. Coordination with CT DEEP may also be required for projects located within areas mapped by the Connecticut N atural Diversity Database. For work within tidal, coastal or navigable waters or in tidal wetlands, permitting will be required with the CT DEEP LWRD. B.8.1 Municipal Permitting See Section 1.5 for general local permitting guidance. • For the installation of new culverts and the replacement of culverts that involve substantial disturbance of soil, water or vegetation which would regularly fall under the review and approval requirements of certain local authorities (i.e., Planning and Zoning Authority; Inland Wetlands Commission; Public Works Department; Historic District Commission), the utility shall at least notify and consult with such local authority, or its designated agent or staff, toward the development of mutually agreeable schedules and procedures for the proposed activity. • For the replacement of culverts involving only minor disturbance of soil, water or vegetation which would regularly fall under the review and approval requirements of certain local authorities, the utility shall make local authorities or their designated agent or staff aware of such ongoing activities. B.8.2 CT Department of Energy & Environmental Protection If the project requires formal permitting with the ACOE, copies of the application should be forwarded to CT DEEP for review under Section 401 of the Clean Water Act. CT DEEP requires that a PGP Addendum form be completed and submitted along with the ACOE application. If a culvert project falls within areas mapped by the Connecticut Natural Diversity Database or falls within 0.50 miles upstream or downstream of a mapped area, a data request and possible coordination will be required with the Natural Diversity Database. If a culvert project is located within tidal, coastal or navigable waters of the state or in tidal wetlands, permitting will be required with the CT DEEP LWRD. For new projects a Structures, Dredging and Fill Permit and/or a Tidal Wetlands Permit will be required. For replacement structures which were previously permitted, or which were in place prior to June 24, 1939, a Certificate of Permission may only be required, which entails a shorter permitting process. B.8.3 U.S. Army Corps of Engineers See Section 1.7 for general ACOE permitting requirements. Open bottom arches, bridge spans or embedded culverts are preferred over traditional culverts and are required for SV projects. However, where site constraints make these approaches impractical, the ACOE should be consulted. New bridge or open-bottom structure crossings may be conducted under SV or PCN if the following criteria are met in addition to meeting any applicable general criteria listed in section 1.7 of this manual: • The work spans at least 1.2 times the watercourse bank full width; Eversource Best Management Practices Manual –January 2022 Appendix B B-10 • The structure has an openness ratio equal to or greater than 0.25 meters; • The structure allows for continuous flow of the 50-year frequency storm flows. New culvert installations may be conducted under SV if the work complies with the general conditions and SV criteria of the CT GPs. The following are SV criteria that are commonly applicable to new culvert installations in utility right of ways: • Work is conducted in accordance with the design requirements listed in Section 3.1.3 of the BMP Manual; Plastic and High Density Polyethylene Pipes (HDPE) are not used; • The work results in less than 5,000 square feet of impacts to wetlands or Waters of the United States; • Any unconfined in-stream work, including construction, installation or removal of sheet pile coffer dam structures, is conducted during the low-flow period between July 1 and September 30, except in instances where a specific written exception has been issued by the Connecticut Department of Energy & Environmental Protection. However, installation of coffer dams, other than sheet pile coffer dams, is not restricted to the low-flow period; • No open trench excavation is conducted within flowing waters. Work within flowing waters can be avoided by using temporary flume pipes, culverts, coffer dams, etc. to isolate work areas and maintain normal flows; • The tributary watershed to the culvert does not exceed 1.0 square mile (640 acres); • The culvert gradient (slope) is not steeper than the streambed gradient immediately upstream or downstream of the culvert; • For a single box or pipe arch culvert crossing, the inverts are set not less than 12 inches below the streambed elevation; • For a multiple box or pipe arch culvert crossing, the inverts of one of the boxes or pipe arch culverts are set not less than 12 inches below the elevation of the streambed; • For a pipe culvert crossing, the inverts are set such that not less than 25% of the pipe diameter or 12 inches, whichever is less, is set below the streambed elevation; • The culvert is backfilled with natural substrate material matching upstream and downstream streambed substrate; • The structure does not otherwise impede the passage of fish and other a quatic organisms; • The structure allows for continuous flow of the 50-year frequency storm flows; • The work does not result in direct or secondary impacts to Special Wetlands, Threatened, Endangered or Special Concern Species, or Significant Natural Communities identified by the Connecticut Natural Diversity Database. Work within 750 feet of vernal pools shall be minimized; • The project does not require an ACOE permit with associated construction activities within 100 feet of Special Wetlands; • The project does not result in fill placed within a FEMA established floodway, unless the applicant has a State of Connecticut Flood Management Certification pursuant to section 25-68d of the Connecticut General Statutes; Eversource Best Management Practices Manual –January 2022 Appendix B B-11 • The project does not result in fill pl aced within a FEMA established floodplain that would adversely affect the hydraulic characteristics of the floodplain; • The project does not entail stormwater detention or retention in inland waters or wetlands; • The project is not located in a segment of a National Wild and Scenic River System (includes rivers officially designated by Congress as active study status rivers for possible inclusion) or within 0.25 miles upstream or downstream of the main stem or tributaries to such a system; • The project has no potential for an effect on a historic property which is listed or eligible for listing in the National Register of Historic Places; • The project does not impinge upon the value of any National Wildlife Refuge, National Forest, or any other area administered by the U.S. Fish and Wildlife Service, U.S. Forest Service or National Park Service. • Appropriate BMPs are employed with regard to sedimentation and erosion controls (General Condition 20). New culvert installations may be conducted under PCN if the work complies with the general conditions and PCN criteria of the GP. The following are PCN criteria that are commonly applicable to new culvert installations in utility right of ways: • Work is conducted in accordance with the design requirements listed in Section 3.1.3 of the BMP Manual; • The work results in less than one acre of impacts to wetlands or Waters of the United States; • The project does not result in fill placed within a FEMA established floodplain that would adversely affect the hydraulic characteristics of the floodplain; • There is no practicable alternative location for the crossing that would have less environmental impacts; • The use of a bridge or open-bottom structure is determined to be not practicable; • For a single box or pipe arch culvert crossing, the inverts are set not less than 12 inches below the streambed elevation; • For a multiple box or pipe arch culvert crossing, the inverts of one of the boxes or pipe arch culverts are set not less than 12 inche s below the elevation of the streambed; • For a pipe culvert crossing, the inverts are set such that not less than the pipe diameter or 12 inches, whichever is less, is set below the streambed elevation; • The culvert is backfilled with natural substrate material matching upstream and downstream streambed substrate; • The culvert has an openness ratio equal to or greater than 0.25 meters; • The structure does not result in a change in the normal water surface elevation of the upstream waters or wetlands; • The structure allows for continuous flow of the 50-year frequency storm flows; • Appropriate BMPs are employed with regard to sedimentation and erosion controls (General Condition 20). Eversource Best Management Practices Manual –January 2022 Appendix B B-12 New culvert installations that cannot meet SV or PCN criteria may require review under an IP. The ACOE should be consulted before assuming an IP will be required, as exceptions can be made under certain circumstances. In-kind replacement of culverts using the same materials is exempt from Section 404 of the Clean Water Act, and does not require permitting with the ACOE. The ACOE, however, should be consulted before assuming an activity is exempt from their jurisdiction. Consult with Eversource Environmental Licensing and Permitting. Bridge or open-bottom structure replacements may be conducted under SV if the conditions for a new bridge or open -bottom structure replacement have been met. In addition, bridge or open-bottom structure replacements should not result in a change in the normal surface elevation of the upstream waters or wetland, and the replacement structure should have a riparian bank on one or both sides for wildlife passage. Culvert replacements may be conducted under SV if the conditions for new culvert installation are met. Bridge or open-bottom structure replacements may be conducted under PCN if the conditions for a new bridge or open-bottom structure replacement have been met. Culvert replacements may be conducted under PCN if the following conditions are met: • The work results in 5,000 square feet to less than one acre of impacts to wetlands or Waters of the United States; • The use of a bridge or open-bottom structure is determined to be not practicable; • For a single box or pipe arch culvert crossing, the inverts are set not less than 12 inches below the streambed elevation; • For a multiple box or pipe arch culvert crossing, the inverts of one of the boxes or pipe arch culverts are set not less than 12 inches below the elevation of the streambed; • For a pipe culvert crossing, the inverts are set such that not less than the pipe diameter or 12 inches, whichever is less, is set below the streambed elevation; • The culvert is backfilled with natural substrate material matching upstream and downstream streambed substrate; • The culvert has an openness ratio equal to or greater than 0.25 meters; • The structure does not result in a change in the normal water surface elevation of the upstream waters or wetlands; • The structure allows for continuous flow of the 50-year frequency storm flows; • Appropriate BMPs are employed with regard to sedimentation and erosion controls (General Condition 20). APPENDIX C Table of Contents C-i Appendix C C.1 Applicable Laws/Regulations ............................................................C- 1 C.2 Geographic Areas Subject to Jurisdiction ...........................................C- 1 C.2.1 Endangered Species ..............................................................C-2 C.2.2 Vernal Pools ........................................................................C- 2 C.2.3 Essential Fish Habitat and Wild & Scenic River Designation ........C- 2 C.2.4 Cold Water Fisheries Resources ..............................................C- 3 C.2.5 Outstanding Resource Waters ................................................C- 3 C.2.6 Historic and Cultural Resources ..............................................C- 3 C.3 Applicable Regulatory Agencies ........................................................C- 3 C.4 Maintenance, Repair, or Emergency Projects .......................................C-4 C.4.1 Maintain, Repair and/or Replace .............................................C- 4 C.4.2 Emergency Projects ..............................................................C- 4 C.5 Municipal Permitting .......................................................................C- 5 C.6 MA Department of Environmental Protection ......................................C- 7 C.7 U.S. Army Corps of Engineers ..........................................................C- 8 C.8 Temporary Stream Crossings .........................................................C- 13 C.8.1 U.S. Army Corps of Engineers ..............................................C- 13 Appendix C C-1 Eversource Best Management Practices Manual –January 2022 Appendix C – Massachusetts Environmental Regulations C.1 Applicable Laws/Regulations In Massachusetts, there are no fewer than nine potentially pertinent regulatory programs associated with activities proposed in environmentally sensitive areas. The following list of laws and regulations are most likely to apply to electrical utility projects in the Commonwealth. • Massachusetts Wetlands Protection Act (M.G.L. 131 § 40) (MA WPA) • Municipal wetland bylaws/ordinances (varies by municipality) • Massachusetts Endangered Species Act (M.G.L. 131A) (MESA) • “Chapter 91” Public Waterfront Act (M.G.L. c. 91 §§ 1 through 63) • Massachusetts Environmental Policy Act (M.G.L. c. 30 §§ 61 through 62H) (MEPA) • Section 10 of the Rivers and Harbors Act of 1899 (33 U.S.C. § 403) • Section 401 of the Clean Water Act (33 U.S.C. § 1251; 314 CMR 9.00) o Administrative Consent Order (ACO) • Section 404 of the Clean Water Act (33 U.S.C. § 1344) • Massachusetts Watershed Protection Act (M.G.L. 92A §1/2) (MA WsPA) C.2 Geographic Areas Subject to Jurisdiction The following areas are subject to regulatory jurisdiction by at least one of the regulatory programs discussed in this section: It is important to note that more than one jurisdictional resource area type may be present at any given location. • Massachusetts Wetlands Protection Act Resource Areas: o (Coastal) Land Under the Ocean; Designated Port Areas; Coastal Beaches; Coastal Dunes; Barrier Beaches; Coastal Banks; Rocky Intertidal Shores; Salt Marshes; Land Under Salt Ponds; Land Containing Shellfish; Banks of or Land Under the Ocean, Ponds, Streams, Rivers, Lakes or Creeks that Underlie Anadromous/Catadromous (“Fish Run”); Land Subject to Coastal Storm Flowage o (Inland). Bank; Bordering Vegetated Wetland; Land Under Water Bodies and Waterways; Land Subject to Flooding; 200-foot Riverfront Area; and the 100-foot Buffer Zone to Bank and BVW • Areas subject to municipal wetlands bylaws or ordinances (note: varies by community) • Estimated and/or Priority Habitat of State-listed Rare Species • Outstanding Resource Waters (ORWs; include Certified Vernal Pools, public surface water drinking supplies, tributaries to drinking water supplies and vegetated wetlands adjacent thereto) • Essential Fish Habitat (EFH) • Areas of Critical Environmental Concern (ACECs) • Great Ponds Appendix C C-2 Eversource Best Management Practices Manual –January 2022 • Navigable waterways • Wild and Scenic Rivers • Quabbin Reservoir, Ware River and Wachusett Reservoir watersheds C.2.1 Endangered Species The Massachusetts Natural Heritage and Endangered Species Program (NHESP), a department of the Massachusetts Division of Fisheries and Wildlife (MassWidlife) maintains the current list of rare and endangered species and species of special concern in Massachusetts. Publicly available data only allows for identification of designated Priority Habitats of Rare Species and Estimated Habitats of Rare Wildlife, not specific species information. Priority and Estimated Habitat locations are available online via the Massachusetts Geographic Information System (MassGIS) viewer. Species specific information is provided for planned linear transmission maintenance activities which are reviewed by NHESP as part of Eversource’s annual Operation and Maintenance (O&M) Plan. Projects/ activities which are not covered in the O&M Plan must file an independent request for information or initiate coordination with NHESP through Eversource Environmental Licensing and Permitting. Applicable regulations and agency are listed below: • Massachusetts Endangered Species Act: 321 CMR 10.00 – Division of Fisheries and Wildlife – NHESP C.2.2 Vernal Pools NHESP maintains a database of certified and potential vernal pools in Massachusetts. These data are available on the NHESP website and MassGIS. Certified Vernal Pools (CVP) are considered Outstanding Resource Waters (ORWs). The current version of the Department of the Army General Permits for the Commonwealth of Massachusetts (MA GPs), effective date April 16, 2018 (expiration date: April 5, 2023) includes General Conditions for protection of vernal pools, regardless of whether or not the vernal pool is certified by NHESP, and including the vernal pool depression, the vernal pool envelope (area within 100 feet of the vernal pool depression’s edge), and the critical terrestrial habitat (area within 100-750 feet of the vernal pool depression’s edge). Temporary impacts associated with construction mats in previously disturbed areas of existing utility projects rights-of-way are exempt from GP requirements regarding work in the vernal pool envelope or critical terrestrial habitat, provided that a V egetation Management Plan (VMP) exists that avoids, minimizes and mitigates impacts to aquatic resources. Applicable regulations and agencies for Certified Vernal Pools (CVPs) are listed below: • Wetlands Protection Act: 310 CMR 10.00 – Municipal Conservation Commissions (and MassDEP) • 401 Water Quality Certification for Discharge of Dredged or Fill Material, Dredging, and Dredged Material Disposal in Waters of the U.S. within the Commonwealth: 314 CMR 9.00 – MassDEP • Department of the Army General Permits for the Commonwealth of Massachusetts – ACOE C.2.3 Essential Fish Habitat and Wild & Scenic River Designation Essential Fish Habitat (EFH) is a habitat essential for spawning, breeding, feeding, or growth to maturity of federally managed species. This website provides more information: https://www.fisheries.noaa.gov/region/new-england-mid-atlantic#habitat. Consultation Appendix C C-3 Eversource Best Management Practices Manual –January 2022 with the ACO is recommended to confirm the location of Essential Fish Habitat with respect to a proposed project. Massachusetts has approximately 8,229 miles of river, of which 147.1 miles are designated as wild & scenic, as summarized below: • Nashua River (Main Stem from the confluence of the North and South Rivers in Lancaster, and extending north to the MA-NH border; some geographic exclusions) • Squannacook River (from headwaters in Ash Swamp/Townsend, extending downstream to the confluence with the Nashua River in Shirley/Ayer; some geographic exclusions) • Nissitissit River (from headwaters in Brookline (NH) to confluence with the Nashua River in Pepperell) • Sudbury River (14.9-mile segment from Danforth Street Bridge/Framingham downstream to the Route 2 Bridge/Concord; 1.7 -mile segment • Assabet River • Concord River • Westfield River (Main Stem, East Branch, Middle Branch, West Branch, and named tributaries • Taunton River (main stem from headwaters at the confluence of the Town and Matfield Rivers (Bridgewater) downstream 40 miles to confluence with the Quequechan River at the Route 195 Bridge (Fall River) Currently, there are no river segments under study in Massachusetts for National Wild and Scenic designation (https://www.rivers.gov/study.php). Wild and Scenic designations should be verified via the National Wild and Scenic Rivers System website (https://www.rivers.gov/massachusetts.php) during project planning and permitting. The ACOE reviews projects for impacts to both EFH and National Wild and Scenic Rivers. • Department of the Army General Permits for the Commonwealth of Massachusetts – ACOE C.2.4 Cold-water Fishery Resources The Massachusetts Division of Fisheries and Wildlife (MassWildlife) maintains a list of waters that are known to have cold-water fishery resources (CFRs) which are waters in which the mean of the maximum daily temperature over a seven day period generally does not exceed 68°F (20°C) and, when other ecological factors are favorable (such as habitat), are capable of supporting a year round population of cold-water stenothermal aquatic life. CFRs are not currently regulated in and of themselves in Massachusetts. However, MassDEP is particularly concerned with water quality impacts to CFRs due to erosion and sedimentation as a result of construction projects. Appendix C C-4 Eversource Best Management Practices Manual –January 2022 C.2.5 Outstanding Resource Waters Outstanding Resource Waters (ORWs) include Certified Vernal Pools (CVPs), surface drinking water supplies, tributaries to surface drinking water supplies and vegetated wetlands adjacent thereto. CVPs are designated by NHESP and locations are available through MassGIS. Locations of surface drinking water supplies and other ORWs, typically identified as Zone A, are also available through MassGIS. The applicable regulations and agency are listed below: • 401 Water Quality Certification for Discharge of Dredged or Fill Material, Dredging, and Dredged Material Disposal in Waters of the U.S. within the Commonwealth: 314 CMR 9.00 – MassDEP C.2.6 Historic/Cultural Resources The Massachusetts Historical Commission (MHC) is the State Historical Preservation Office (SHPO) and, along with the Board of Underwater Archaeological Resources (BUAR), are the state agencies responsible for protecting the Commonwealth’s historic and cultural resources. Additional stakeholders for cultural resources include the Massachusetts Commission on Indian Affairs, Native American tribes with interests in the state, and local historical commissions. C.3 Applicable Regulatory Agencies Activities subject to jurisdiction under the above-referenced programs will generally be subject to review by one or more regulatory agencies (refer to list below). New stream and wetland crossings not related to maintenance will require permitting with municipal Conservation Commissions, and may require permitting with the U.S. Army Corps of Engineers (ACOE) and Massachusetts Department of Environmental Protection (MassDEP) under Sections 404 and 401 of the Clean Water Act. Any non -maintenance work within Land Under Water will require permitting with the MassDEP Division of Wetlands and Waterways. Coordination with NHESP may also be required for projects located within areas mapped as Priority and/or Estimated Habitat for state-listed rare species. For work within navigable waters, consultation may be required with the Massachusetts Office of Coastal Zone Management (MA CZM). • Municipal Conservation Commissions • Massachusetts Department of Environmental Protection (MassDEP) Division of Wetlands and Waterways • Massachusetts Division of Fisheries and Wildlife: Natural Heritage and Endangered Species Program (NHESP) • Massachusetts Executive Office of Energy and Environmental Affairs (EEA) • United States Army Corps of Engineers (ACOE) New England District • Massachusetts Office of Coastal Zone Management (MA CZM) • Massachusetts Division of Conservation and Recreation (MA DCR) C.4 Maintenance, Repair, or Emergency Projects Most regulatory programs contain provisions that allow normal maintenance of existing structures and/or response to emergency situations that require immediate attention. C.4.1 Maintain, Repair and/or Replace Exemptions or considerations for maintenance, repair, and/or replacement of existing electrical utility structures exist in some environmental regulations, but not all. The exemptions are limited to work related to existing and lawfully located structures where Appendix C C-5 Eversource Best Management Practices Manual –January 2022 no change in the original structure or footprint is proposed. It is not for the selected contractor of a particular project to make a determination as to whether an activity is exempt. This determination will be made prior to the commencement of work by the Eversource project manager in consultation with Eversource Environmental Licensing and Permitting. These exemptions/considerations are afforded at: • MAWPA (M.G.L Chapter 131, § 40, paragraph 1) • MAWPA regulations for Riverfront Area (310 CMR 10.58(6)) • MEPA regulations (301 CMR 11.01(2)(b)(3)) • 33 CFR Part 323.4(a)(2) • MESA (M.G.L. Chapter 131A, § 3; 321 CMR 10.14(5-7) and (12) • MAWPA (350 CMR 11.05(11) and (12)) • National Pollutant Discharge Elimination System (NPDES), Construction General Permit (as modified effective February 16, 2012) Certain operation and maintenance activities that will directly impact Waters of the United States through the discharge of fill (e.g., construction mats) are subject to Sections 401 and 404 of the Clean Water Act. C.4.2 Emergency Projects Emergency provisions are generally afforded to activities that need to abate conditions that pose a threat to public health or safety. These provisions generally do not allow work beyond what is necessary to abate the emergency condition and will generally require an after-the-fact permit. It is not for the selected contractor of a particular project to make a determination as to whether an activity is an emergency. This determination will be made prior to work by the Eversource project manager, in consultation with Eversource environmental staff. It is important to note that invocation of an emergency provision does not release the project proponent from reporting requirements. Emergency provisions are afforded at: • MAWPA regulations (310 CMR 10.06) • MEPA (301 CMR 11.00) • MA 401 WQC (314 CMR 9.12) • Chapter 91 (310 CMR 9.20) • MESA (321 CMR 10.15) C.5 Municipal Permitting Work within wetlands, watercourses and Buffer Zones typically requires permitting with municipal Conservation Commissions. Work that entails “maintaining, repairing or replacing, but not substantially changing or enlarging, an existing and lawfully located structure or facility used in the service of the public and used to provide electric service” is exempt under the Massachusetts Wetlands Protection Act (MA WPA) per MGL Chapter 131 Section 40. However, individual municipalities may establish their own wetland s bylaws under Home Rule authority which could require permitting for operation and maintenance activities. The following table lists communities in which Eversource operates and maintains infrastructure and which have a wetland bylaw. Appropriate municipal Appendix C C-6 Eversource Best Management Practices Manual –January 2022 permitting or notification should be completed in these towns as required prior to conducting operation and maintenance activities. Bylaws may be revised, or new bylaws enacted, at any time. Consult with Eversource Environmental Licensing and Permitting prior to the commencement of work. TABLE C-1 Eversource Energy Communities with Municipal Wetland Bylaws1 Community Date of Bylaw Utility Maintenance Exemption Notification Required Acton 7/8/2003 Yes No Amherst 2/12/2014 Yes Yes Andover 5/11/1999 Yes Yes Aquinnah 6/23/2020 Yes Yes Arlington 5/15/2000 No Yes Ashland 5/6/2009 Yes Yes Attleboro 12/12/2007 No No Auburn 5/1/2012 Yes Yes Avon 5/7/2019 Yes Yes Barnstable 11/7/1987/rev. 7/7/2003 Yes Yes Bedford 1987/rev. 2016 Yes Yes Belchertown 6/7/2020 Yes Yes Bellingham 12/2015 No Yes Berlin 2/15/2021 Yes Yes Bolton 5/7/2012 Yes No Boston 12/11/2019 Yes Yes Bourne 10/26/2009 No Yes Brewster 1/1/2013 Yes Yes Bridgewater 11/13/1990 Yes Yes Brookline 5/28/2013 Yes Yes Burlington 5/2021 Yes Yes Canton 5/10/2017 Yes Yes Carlisle 2002 Yes No Carver 1998 Yes Yes Chatham 5/10/2004 Yes Yes Chicopee 4/3/2002 Yes Yes Chilmark 10/12/1993 No Yes Dartmouth 1990/rev. 8/25/2015 Yes Yes Dedham 11/182013 Yes Yes Deerfield 11/6/1989 Yes Yes Dennis 5/5/1989 Yes Yes Dover 5/2/1994 Yes Yes Duxbury Yes No East Longmeadow 10/1992 Yes Yes Eastham 1980/rev. 1999 Yes Yes Edgartown 1985/rev. 6/25/1991 No Yes Fairhaven 5/10/1988 Yes No Falmouth 4/2/1979/rev. 7/16/1993 Yes Yes Appendix C C-7 Eversource Best Management Practices Manual –January 2022 TABLE C-1 Eversource Energy Communities with Municipal Wetland Bylaws1 Community Date of Bylaw Utility Maintenance Exemption Notification Required Framingham 4/26/2005 Yes Yes Grafton 5/11/1987 Yes Yes Greenfield 11/23/2001 Yes No Hadley 5/1/2008 No Yes Hampden 8/5/1992 Yes Yes Harwich 7/1/2003/rev. 11/25/2020 No Yes Holden 2011 Yes Yes Holliston 5/2021 Yes Yes Hopkinton 5/2/1995/rev. 5/7/2012 Yes Yes Holyoke 11/2005 Yes Yes Kingston 2004 No Yes Leicester 11/2015 Yes Yes Lenox3 12/18/1985 Yes No Lexington 5/3/1982 No Yes Lincoln 3/24/2007 No Yes Longmeadow 10/2000 Yes No Ludlow 5/1/2002 Yes No Marshfield 1988/rev. 4/23/2018 Yes Yes Mashpee 2/1/1988 Yes Yes Maynard 12/3/2005 Yes Yes Medfield 1926 Yes No Medway 7/2014 Yes Yes Milford 5/2010 Yes No Millis 5/13/1191 Yes No Millville 5/13/2013 Yes Yes Natick 4/27/2000 Yes No Needham 9/1/1988 Yes Yes New Bedford 2017 Yes Yes Norfolk 11/9/2010 Yes Yes Northampton 8/17/1989 Yes Yes Northborough 5/21/1990 Yes Yes Northbridge 5/6/2008 Yes Yes Oak Bluffs 4/1983 No Yes Orleans 5/5/1987 Yes Yes Palmer 8/12/2013 Yes Yes Pelham 5/2/1987 Yes Yes Pembroke 4/22/2008 Yes No Plymouth 4/5/1989 Yes Yes Plympton 5/16/2012 Yes Yes Provincetown 5/2019 Yes Yes Richmond 5/2015 Yes Yes Rochester As of 12/2015 Yes Yes Appendix C C-8 Eversource Best Management Practices Manual –January 2022 TABLE C-1 Eversource Energy Communities with Municipal Wetland Bylaws1 Community Date of Bylaw Utility Maintenance Exemption Notification Required Sandwich 5/4/1992 Yes Yes Sharon As of 12/2015 Yes No Sherborn 2013 Yes No Shutesbury 5/2/1987 Yes Yes Southampton 9/21/2021 Yes Yes Southborough 4/10/1995 Yes Yes South Hadley 12/27/2005 No Yes Southwick 6/6/1989 Yes Yes Springfield 5/5/1993 Yes Yes Stoneham 4/2013 Yes Yes Stow 5/21/2003 No Yes Sudbury Yes Yes Sunderland 4/27/1990 Yes Yes Sutton 5/11/2015 Yes Yes Tisbury 1/1/1983 Yes No Truro 9/30/2010 No Yes Upton 2009 Yes Yes Walpole 2002 Yes Yes Wareham 4/25/2016 Yes Yes Watertown 10/2010 Yes Yes Wayland 5/1/2002 Yes No Wellfleet 4/20/1986/rev. 10/6/2021 Yes Yes Wendell 3/10/1988 Yes Yes West Tisbury 6/3/2004 Yes Yes Westborough 10/20/2008 Yes Yes Westfield 5/20/2003 Yes Yes Westport4 4/11/1995 No Yes Westwood 1989 Yes Yes Wilbraham 5/27/1997 Yes Yes Winchester No Yes Woburn 6/24/1987 Yes Yes Worcester 7/1/2007 Partial Yes Yarmouth 12/1/2016 No Yes 1 Information based on the Massachusetts Association of Conservation Commissions website as of 2019 and municipal websites. 2 Refer to municipal bylaws prior to conducting work in the community. 3 Berkshire Scenic Mountain Act, as adopted by the Town of Lenox and administered by the Lenox Conservation Commission. 4 Town of Westport Soil Conservation Bylaw, as administered by the Westport Conservation Commission. . C.6 MA Department of Environmental Protection Review and approval under the Commonwealth’s Water Quality Certification Regulations Appendix C C-9 Eversource Best Management Practices Manual –January 2022 is required for “discharge of dredged or fill materials, dredging, and dredged material disposal activities in waters of the United States within the Commonwealth which require federal licenses or permits and which are subject to state water quality certification under 33 U.S.C. 1251, et seq. The federal agency issuing a permit initially determines the scope of geographic and activity jurisdiction” (314 CMR 9.01(2)). An individual Water Quality Certification is required from the Massachusetts Department of Environmental Protection (MassDEP) for any activity identified at 314 CMR 9.04. In accordance with 314 9.04 (4) activities which are exempt from MGL Chapter 131 Section 40 but are subject to 33 U.S.C. 1251, et seq., and will result in any discharge of dredge or fill material to bordering vegetated wetlands or land under water require an individual 401 Water Quality Certification. Eversource entered into an Administrative Consent Order (ACO) with MassDEP in 2017. This ACO serves as a general permit under the 401 Water Quality regulations (314 CMR 9.00) and establishes general conditions for routine operation and maintenance activities within existing ROWs. C.7 U.S. Army Corps of Engineers Work within wetlands and waters of the United States is subject to jurisdiction under Section 404 of the Clean Water Act, which is administered by the ACOE. The General Permits for the Commonwealth of Massachusetts (MA GPs) establish categories for projects based on their nature of impacts. The MA GPs were most recently issued on April 16, 2018, and expire on April 5, 2023. Certain minor activities are eligible for Self-Verification (SV), which requires submittal of a Self-Verification Notification Form (SVNF) prior to the commencement of work. Activities eligible for Self-Verification are authorized under the MA GPs and may proceed without written verification from the ACOE as long as the SVNF has been submitted and the activity meets the terms and conditions of the applicable MA GPs. Activities requiring Pre-Construction Notification (PCN) require the submittal of an application to the ACOE, followed by a screening of the application by the ACOE, the U.S. Fish and Wildlife Service, U.S. Environmental Protection Agency, National Marine Fisheries Service, MassDEP, and consultation with the Massachusetts Historical Commission, Tribal Historic Preservation Officers (THPOs) and the Massachusetts Board of Underwater Archaeological Resources (BUAR). PCN projects may not proceed until written verification from the ACOE is received. An Individual Permit (IP) requires a formal permit application to be submitted to the ACOE. The application is reviewed in detail by both state and federal agencies, and a public notice is released for public comment. Projects which trigger an Individual Permit generally result in significant impacts to wetlands and/or watercourses outside the limits of the MA GPs. Work within, or above, Navigable Waters is also administered by the ACOE under Section 10 of the Rivers and Harbors Act of 1899. ACOE permitting does not apply to activities that fall under the maintenance exemption set forth at 33 CFR 323.4(a)(2) – Discharges Not Requiring Permits: “Maintenance, including emergency reconstruction of recently damaged parts, of currently serviceable structures such as dikes, dams, levees, groins, riprap, breakwaters, causeways, bridge abutments or approaches, and transportation structures. Maintenance does not include any modification that changes the character, scope, or size of the original fill design. Emergency reconstruction must occur within a reasonable period of time after damage occurs in order to qualify for this exemption.” Appendix C C-10 Eversource Best Management Practices Manual –January 2022 Maintenance projects that occurred prior to the ACOE jurisdiction over fill activities, or that were properly permitted, can proceed under the maintenance exemption noted above, provided that the same temporary fill areas are used. However, it is recommended that a formal determination be requested from the ACOE to confirm these activities are exempt. The repair, rehabilitation or replacement of a previously authorized, currently serviceable structure or fill (with some minor deviations in the structure’s configuration or filled area) are regulated under MA GP1 and subject to SV or PCN. Also, operation and maintenance related activities that do not meet the above exemption may qualify for SV. In that case, it is recommended that a copy of the SVNF be submitted to MassDEP. The MA GPs are listed below. MA GPs specifically, and typically, applicable to utility projects are emphasized by bold italic font: GP1. Repair, Replacement and Maintenance of Authorized Structures and Fills GP2. Moorings GP3. Pile-Supported Structures, Floats and Lifts GP4. Aids to Navigation, and Temporary Recreational Structures GP5. Dredging, Disposal of Dredged Material, Beach Nourishment, and Rock Removal and Relocation GP6. Discharges of Dredged or Fill Material Incidental to the Construction of Bridges GP7. Bank and Shoreline Stabilization GP8. Residential, Commercial and Institutional Developments, and Recreational Facilities GP9. Utility Line Activities GP10. Linear Transportation Projects Including Stream Crossings GP11. Mining Activities GP12. Boat Ramps and Marine Railways GP13. Land and Water-Based Renewable Energy Generation Facilities and Hydropower Projects GP14. Temporary Construction, Access, and Dewatering GP15. Reshaping Existing Drainage Ditches, New Ditches, and Mosquito Management GP16. Response Operations for Oil and Hazardous Substances GP17. Cleanup of Hazardous and Toxic Waste GP18. Scientific Measurement Devices GP19. Survey Activities GP20. Agricultural Activities GP21. Fish and Wildlife Harvesting and Attraction Devices and Activities GP22. Habitat Restoration, Establishment and Enhancement Activities GP23. Previously Authorized Activities In general, the following cumulative thresholds apply for determining the level of ACOE permitting required: Table C-2 MA GPs Permits Limits Resources SV Limits (SV Eligible) PCN Limits (PCN Eligible) IP Limits (IP Required) Non-tidal waters of the US 0 to 5,000 sf 5,000 sf to 1 acre >1 acre Tidal waters of the US Not eligible All discharges ≤1/2 acre >1/2 acre SAS in tidal waters of the US excluding vegetated shallows Not eligible All discharges ≤1,000 sf >1,000 sf Appendix C C-11 Eversource Best Management Practices Manual –January 2022 SAS in tidal waters of the US consisting of vegetated shallows only Not eligible All discharges ≤100 sf (compensatory mitigation is required >100 sf *Special Aquatic Sites (SAS) consist of wetlands, mud flats, vegetated shallows, sanctuaries and refuges, coral reefs, and riffle and pool complexes. These are defined at 40 CFR 230 Subpart E. Stream and wetland crossings are only subject to jurisdiction under the ACOE if there is a discharge of dredge or fill material into wetlands or waters of the United States . Equipment access through a stream or wetland with no structural BMP is not regulated by the ACOE if there is no discharge of dredge or fill material (note that equipment rutting as a result of not using an appropriate BMP can be considered a “disch arge of dredge material”). Similarly, the use of a timber or rail car bridge that extends from bank to bank with no stream impacts is not regulated by the ACOE. The use of timber mats, stone, and log corduroy is considered “fill material” by the ACOE under the MA GPs, and must be calculated to determine overall impacts. Maintenance, including emergency reconstruction of currently serviceable structures, is exempt from ACOE jurisdiction and does not require formal permitting. Maintenance do es not include any modification that changes the character, scope, or size of the original fill design. Emergency reconstruction must occur within a reasonable period of time after damage occurs to qualify for this exemption. New culvert installation or existing culvert replacements may require permitting with local Conservation Commissions under the MAWPA, and may also require permitting with the ACOE under Section 404 of the Clean Water Act or Section 10 of the Rivers and Harbors Act of 1899, and the MassDEP under Section 401 of the Clean Water Act. Stream and wetland crossings (including culvert installations) that involve the discharge of dredge and fill material may be conducted under SV if the following criteria are met. • The use of construction mats of any area can be used to conduct activities that were previously authorized, authorized under Self-Verification, or not subject to regulation. Other temporary or permanent fill and associated secondary impacts must meet the SV limits. • Authorized construction mats must be removed immediately upon work completion, and the wetlands must be restored per the General Conditions. Appendix C C-12 Eversource Best Management Practices Manual –January 2022 The project has no potential for an effect on a historic property within the permit area or any known historic property that may occur outside the permit area. • Any in-water work controls that encroach upon more than 25 percent of the stream width are limited to a Time of Year (TOY) restriction in consideration of spawning, breeding and migration to maintain upstream fish passage. Activities within streams proposed during the TOY restrictions are generally ineligible for SV authorization. • The work does not result in direct or secondary impacts to Special Aquatic Sites. • No work occurs in Navigable Waters (waters subject to the ebb and flow of the tide and, in Massachusetts, the non-tidal consist of the Merrimack River, Connecticut River, and Charles River to the Watertown Dam). • Span streams or size culverts or pipe arches such th at they are at least 1.2 times the bankfull width. Spans are strongly preferred as they avoid or minimize disruption to the streambed and avoid entire streambed reconstruction and maintenance inside the culvert or pipe arch, which may be difficult in smaller structures. Footings and abutments for spans and scour protection should be landward of 1.2 times bankfull width. • Embed culverts or pipe arches below the grade of the streambed. This is not required when ledge/bedrock prevents embedment, in which case spans are required. The following depths are recommended to prevent streambed washout, and ensure compliance and long-term success: o ≥ 2 feet for box culverts and pipe arches, or o ≥ 2 feet and at least 25% for round pipe culverts. • Match the culvert gradient (slope) with the stream channel profile. • Construct crossings with a natural bottom substrate within the structure matching the characteristics of the substrate in the natural stream channel and the banks (mobility, slope, stability, confinement, grain and rock size) at the time of construction and over time as the structure has had the opportunity to pass substantial high flow events. • Construct crossings with appropriate bed forms and streambed characteristics so that water depths and velocities are comparable to those found in the natural channel at a variety of flows at the time of construction and over time. In order to provide appropriate water depths and velocities at a variety of flows and especially low flows, it is usually necessary to reconstruct the streambed (sometimes including a low flow channel) or replicate or preserve the natural channel within the structure. Otherwise, the width of the structure needed to accommodate higher flows will create conditions that are too shallow at low flows. Flows could go subsurface within the structure if only large material is used without smaller material filling the voids. • Openness, which is the is the cross-sectional area of a structure opening divided by its crossing length when measured in consistent units, is > 0.82 feet (0.25 meters). Banks on each side of the stream inside the crossing matching the horizontal profile of the existing stream and banks outside the crossing are recommended. To prevent failure, all constructed banks should have a height to width ratio of no greater than 1:1.5 (vertical:horizontal) unless the stream is naturally incised. Tie these banks into the up and downstream banks and configure them to be stable during expected high flows. Appendix C C-13 Eversource Best Management Practices Manual –January 2022 • The project is not located within a vernal pool depression, or vernal pool envelope, and does not individually or cumulatively impact greater than 25% of the vernal pool critical terrestrial habitat. It is feasible for some temporary impacts associated with the use of construction mats in previously disturbed ROWs to occur within the vernal pool envelope or critical terrestrial habitat if a Vegetation Management Plan demonstrates avoidance, minimization and mitigation impacts to aquatic resources. • Culvert extensions do not qualify for SV. • Culvert projects using slip lining do not qualify for SV, either as new work or maintenance activities. • No open trench excavation in flowing waters. No work in riffles and pools. • The project does not entail stream relocation. • Work is not conducted within riffles or pools. • Normal flows within the stream boundary’s confines must be maintained, i.e., temporary flume pipes, culverts, cofferdams, etc. • Water diversions (i.e., bypass pumping or water withdrawals) may be used immediately up and downstream of the work footprint. • The project is (a) not located in the designated main stem of, or within 0.25 miles up or downstream of the designated main stem of, or in tributaries within 0.25 miles of the designated main stem of a National Wild and Scenic River System; (b) not in “bordering or contiguous wetlands” that are adjacent to the designated main stem of a National Wild and Scenic River; or (c) does not have the potential to alter flows within a river within the National Wild and Scenic River System. • The project is not located within areas containing USFWS or National Marine Fisheries Service (NMFS)-listed species or critical habitat. The project is not “likely to adversely affect” listed species or habitat per the federal Endangered Species Act (ESA) or result in a “take” of any federally-listed threatened or endangered species of fish or wildlife. • The project does not impinge upon the value of any National Wildlife Refuge, National Forest, National Marine Sanctuary, or any other area administered by the U.S. Fish and Wildlife Service, U.S. Forest Service or National Park Service. • The project is not located on ACOE properties and ACOE-controlled easements. • The project does not propose temporary or permanent modification or use of a federal project beyond minor modifications required for normal operation and maintenance. • The project minimizes use of heavy construction equipment, and, where required, either has low ground pressure (typically less than 3 psi) or it must be placed on construction mats. • Construction mats must be placed in the wetland from the upland or from equipment positioned on swamp mats if working within a wetland. • Temporary fill must be stabilized. Unconfined, authorized temporary fill must consist of clean material that minimizes impacts to water quality. Temporary fill placed during the growing season must be removed before the beginning of the next growing season. If temporary fill is placed during the non -growing season, it may remain throughout the following growing season but must be removed before the beginning of the next growing season. Appendix C C-14 Eversource Best Management Practices Manual –January 2022 • Appropriate erosion, sedimentation and turbidity controls are used and maintained during construction. • Appropriate measures must be taken to minimize flooding to the maximum extent practicable. Wetland and stream crossings may be authorized under PCN if the following criteria are met: • The work results in less than one acre of impacts to inland, non -tidal, wetlands or waters of the United States. Stream and wetland crossings that cannot meet SV or PCN criteria may require review under an IP. The ACOE should be consulted before assuming an IP will be required, as exceptions can be made under certain circumstances. C.8 Temporary Stream Crossings C.8.1 U.S. Army Corps of Engineers See Section C.7 for general ACOE permitting requirements for stream crossings. To qualify for SV, temporary stream crossings (typically culverts) that are not spans must be designed in accordance with below. 1) Installed outside of the TOY restrictions and must be removed before the beginning of the TOY restriction of that same season. Temporary crossings that must remain into the TOY restriction will require PCN review. 2) Impacts to the streambed or banks require restoration to their original condition (see “Stream Simulation: An Ecological Approach to Providing Passage for Aquatic Organisms at Road-Stream Crossings,” for stream simulation restoration methods). Use geotextile fabric or other appropriate bedding for stream beds and approaches where practicable to ensure restoration to the original grade. The requirements in GCs 17, 18 and 19 are particularly relevant. 3) Avoid excavating the stream or embedding crossings. 4) For Culverts: a. The water height should be no higher than the top of the culvert’s inlet and the culvert is large enough to pass debris. b. Install energy dissipating devices downstream if necessary to prevent scour. c. The TOY restrictions in GC 18 and the restrictions in GC 17(f) are particularly relevant. 5) Removed upon the completion of work. Impacts to the streambed or banks requires restoration to their original condition using stream simulation methods. In-kind repair, replacement and maintenance of currently serviceable, authorized fills are eligible for SV. However, the conditions of the original authorization apply, and minor deviations in fill design are allowed. In-kind repair and maintenance of culverts that includes an expansion or change in use requires PCN. Replacement of non-serviceable fills, including an expansion or change in use, also requires PCN. In-kind replacement using the same materials is exempt from Section 404 of the Clean Water Act, and does not require permitting with the ACOE. The ACOE, however, should be consulted before assuming an activity is exempt from their jurisdiction. APPENDIX D D-1 FRAC-OUT PLAN Horizontal directional drilling (HDD) for subsurface utility installations is considered to be the most effective and least environmentally damaging technique when compared to traditional mechanical dredging and trenching. This method ensures the placement of the pipeline at the target burial depth with no wetland or water body disturbance. HDD installation is the preferred method for crossing sensitive resources–the alternative is open cut trenching. The HDD procedure uses bentonite slurry, a fine clay material as a drilling lubricant. Directional drilling has the small potential to release bentonite slurry into the surface environment through frac-outs. This term describes the situation caused when th e drilling head and its accompanying inert clay lubricant slurry, hits a subterranean fractured substrate. When the pressurized lubricant slurry reaches the fracture it can follow the fracture up or otherwise force itself to the surface or into the water if drilling is occurring under a waterbody. If a "frac-out” occurs under these water features, the potential exists for the inert clay (a non - toxic bentonite-based substance) to be released into the water column. In large quantities, the release of drilling mud into a waterbody could affect fisheries or other aquatic organisms by settling and temporarily inundating the habitats used by these species. Properly monitoring the slurry pressures and amounts significantly decreases risk of significant quantities o f drilling fluid being released into the environment. Frac-out is most likely to occur near the bore entry and exit points where the drill head is shallow. Should a frac-out occur during HDD operations, the following measures will be taken. • Temporarily suspend forward drilling progress. • Monitor frac-out for 4 hours to determine if the drilling mud congeals. (Bentonite will usually harden, effectively sealing the frac-out location.) • If drilling mud congeals, take no other action that would potentially suspend sediments in the water column. • If drilling mud does not congeal, erect appropriate isolation/containment measures (i.e. turbidity curtains and/or underwater boom and curtain). • If the fracture becomes excessively large, a spill response team would be called in to contain and clean up excess drilling mud in the water. Phone numbers of spill response teams in the area will be on site. • Following containment, evaluate the current drilling profile (i.e. drill pressures, pump volume rates, drilling mud consistency) to identify means to prevent further frac-out events. • If the fracture is mitigated and controlled, forward progress of the drilling may resume. Attachment J NHESP Permit December 13, 2024 Michael Howard Epsilon Associates, Inc. 3 Mill & Main Place, Suite 250 Maynard, MA 01754 RE: Applicant: Michael Howard Project Location: 726 Sandwich Road (within Joint Base Cape Cod) Project Description: Cape Cod Solution Phase II, New Sagamore 345-kV Substation NHESP File No.: 23-8713 Dear Applicant: The Natural Heritage & Endangered Species Program of the Massachusetts Division of Fisheries & Wildlife (the “Division”) received the MESA Project Review Checklist and supporting documentation for review pursuant to the Massachusetts Endangered Species Act (MESA) (MGL c.131A) and its implementing regulations (321 CMR 10.00). The MESA is administered by the Division, and prohibits the Take of state-listed species. The Take of state-listed species is defined as “in reference to animals…harm…kill…disrupt the nesting, breeding, feeding or migratory activity…and in reference to plants…collect, pick, kill, transplant, cut or process…Disruption of nesting, breeding, feeding, or migratory activity may result from, but is not limited to, the modification, degradation, or destruction of Habitat” of state-listed species (321 CMR 10.02). The Division has determined that this Project, as currently proposed, will occur within the actual habitat of the following species: Scientific Name Common Name Taxonomic Group State Status Special ConcernReptileEastern Box TurtleTerrapene carolina Special ConcernButterfly/MothHeath MetarranthisMetarranthis pilosaria Special ConcernButterfly/MothBuck MothHemileuca maia This/These species and their habitats are protected in accordance with the MESA. Based on the information provided and the information contained in our database, the Division finds that a 23-8713NHESP No.Page 2 of 3 Issued December 13, 2024 portion of this project, as currently proposed, must be conditioned to avoid a prohibited Take of state-listed species (321 CMR 10.18(2)(a)). To avoid a prohibited Take of state-listed species, the conditions attached to this letter must be met. Provided the attached conditions are fully implemented and there are no changes to the project plans, this project will not result in a Take of state-listed species. We note that all work is subject to the anti-segmentation provisions (321 CMR 10.16) of the MESA. This determination is a final decision of the Division of Fisheries and Wildlife pursuant to 321 CMR 10.18. Any changes to the proposed project or any additional work beyond that shown on the site plans may require an additional filing with the Division pursuant to the MESA. This project may be subject to further review if no physical work is commenced within five years from the date of issuance of this determination, or if there is a change to the project. Please note that this determination addresses only the matter of state-listed species and their habitats. If you have any questions regarding this letter please contact Emily Holt, Endangered Species Review Assistant, at Emily.Holt@mass.gov, (508) 389-6385. Sincerely, Jesse Leddick Assistant Director cc: Peter DeFusco, NSTAR Electric d/b/a Eversource Energy Attachment: List of Conditions 23-8713NHESP No.Page 3 of 3 Issued December 13, 2024 List of Conditions Applicant: Michael Howard Project Location: 726 Sandwich Road (within Joint Base Cape Cod) Project Description: Cape Cod Solution Phase II, New Sagamore 345-kV Substation NHESP File No.: 23-8713 Heritage Hub Form ID: RC-90082 Approved Plan: Cape Cod Solution Phase II Plan date: 10/25/2024 Revised Date: N/A To avoid a prohibited Take of state-listed species, the following condition(s) must be met: 1.Turtle Protection Plan: A Division-approved qualified biologist shall implement the “ Eastern Box Turtle Protection Plan” (dated 11/14/2024) as written. Any changes to this Plan must be pre-approved by the Division in writing. Turtle exclusion fencing and gates shall remain installed and in good condition until all work and restoration activities are concluded, unless otherwise approved by the Division. 2.Compliance Report: Within thirty (30) days of the completion of work or as otherwise approved by the Division, the Applicant shall submit a brief written report to the Division documenting compliance with the condition(s) required herein, including representative photographs or supplemental documentation as necessary. 3.Ongoing Vegetation Management: Following completion of all Work associated with the Project, ongoing vegetation management and maintenance activities within the ROW within Priority Habitat shall occur in accordance with a Division-approved Yearly Operation Plan and/or Operations and Management Plan, unless otherwise approved by the Division.