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HomeMy WebLinkAbout20140957 Ver 2_10_Appendix_D_FERC Supplemental FERC Info_20170509ATLANTIC COAST PIPELINE, LLC ATLANTIC COAST PIPELINE APPENDIX D Supplemental FERC Upland Construction Information Atlantic Coast Pipeline Atlantic Coast Pipeline Supplemental FERC Upland Construction Information Table of Contents 1.0 NATURE OF ACTIVITY AND APPLICABLE CONSTRUCTION METHODS......1 1.1 GENERAL CONSTRUCTION SEQUENCE, PROCEDURES, AND PLANS.....................................................................................................................1 1.1.1 Survey and Staking......................................................................................2 1.1.2 Clearing and Grading...................................................................................2 1.1.3 Erosion Control Device Installation.............................................................3 1.1.4 Trenching.....................................................................................................3 1.1.5 Pipe Stringing, Bending, and Welding........................................................4 1.1.6 Lowering -in and Backfilling........................................................................4 1.1.7 Hydrostatic Testing......................................................................................5 1.1.8 Cleanup and Restoration..............................................................................5 1.1.9 Access Roads...............................................................................................6 Attachments Attachment 1 - Restoration and Rehabilitation Plan Atlantic Coast Pipeline Nationwide Permit No. 12 — Pre -Construction Notification U.S. Army Corps of Engineers — Wilmington District 1.0 NATURE OF ACTIVITY AND APPLICABLE CONSTRUCTION METHODS This section is intended to provide a better understanding of construction methods, potential impacts, and planned mitigation measures to be implemented during construction to avoid and minimize environmental impacts at sensitive resource crossings such as wetlands and waterbodies. While much of the information referenced in the sections below is not specifically related to the USACE permitting requirements, the detailed information and Plans will be available through the FERC Project Docket (No. CP15-554-000) to all cooperating agencies, including the USACE. 1.1 GENERAL CONSTRUCTION SEQUENCE, PROCEDURES, AND PLANS The ACP will be designed, constructed, operated, and maintained in accordance with U.S. Department of Transportation regulations codified at 49 Code of Federal Regulations (CFR) 192, Transportation of Natural and Other Gas by Pipeline: Minimum Federal Safety Standards; with FERC regulations codified at 18 CFR 380.15, Siting and Maintenance Requirements; and with other applicable Federal and State regulations, except as otherwise specified in the FERC Application or approved by the appropriate regulatory agency. Atlantic will adopt and implement the 2013 versions of the FERC's Upland Erosion Control, Revegetation, and Maintenance Plan (Plan) and Wetland and Waterbody Construction and Mitigation Procedures (Procedures).1 Atlantic additionally will prepare and implement the following construction, restoration, and mitigation plans: • Spill Prevention, Control, and Countermeasures Plan; • Horizontal Directional Drill Fluid Monitoring, Operations, and Contingency Plan; • Timber Removal Plan; • Contaminated Media Plan; • Traffic and Transportation Management Plan; • Invasive Plant Species Management Plan; • Blasting Plan; • Slip Avoidance, Identification, Prevention and Remediation Procedures • Winter Construction Plan; • Plans for Unanticipated Discovery of Historic Properties or Human Remains during Construction; Copies of the FERC's Plan and Procedures are available on the FERC's website at http://www.ferc.gov/industries/gas/enviro/ guidelines.asp. Atlantic Coast Pipeline Nationwide Permit No. 12 — Pre -Construction Notification U.S. Army Corps of Engineers — Wilmington District • Karst Terrain Assessment, Construction, Monitoring and Mitigation Plan; • Restoration and Rehabilitation Plan; • Migratory Bird Plan; • Fire Prevention and Suppression Plan; and • Fugitive Dust Control and Mitigation Plan. A copy of the Spill Prevention, Control, and Countermeasures Plan, and the Plans for Unanticipated Discovery of Historic Properties or Human Remains during Construction, are provided in the Appendices G, and M, of the pre -construction notification. A copy of Restoration and Rehabilitation Plan is located in Attachment 1. Atlantic will also prepare a set of construction alignment sheets, drawings at a scale of one inch equals 200 feet, or similar scale maps that depict the locations of erosion and sediment controls in construction work areas that will be used during construction of ACP. The alignment sheets will incorporate the FERC's Plan and Procedures requirements as well as State and local regulations or guidelines applying the strictest applicable standards, such as the North Carolina Department of Environmental Quality's, 2013 - North Carolina Erosion and Sediment Control Planning and Design Manual. 1.1.1 Survey and Staking Affected landowners will be notified before the preconstruction survey and staking are conducted. After these notifications, Atlantic's survey contractor will stake the pipeline centerlines and limits of the construction right-of-way and additional temporary workspace (ATWS) areas. Wetland boundaries and other environmentally sensitive areas will also be marked at this time. 1.1.2 Clearing and Grading Prior to beginning ground -disturbing activities, Atlantic will fell trees by hand and mow non forested areas outside of the migratory bird nesting and bat summer roosting seasons. Felled woody vegetation would be mechanically removed beginning in April of the following year and prior to grading activities. Atlantic's construction contractors will coordinate with the One -Call systems in West Virginia to have existing underground utilities (e.g., cables, conduits, and pipelines) identified and flagged. Once this process is complete, the clearing crew will mobilize to the construction areas. Fences along the rights-of-way will be cut and braced, and temporary gates and fences will be installed to contain livestock, if present. The clearing crew will then clear the work area of vegetation and other obstacles, including trees, stumps, logs, brush, and rocks. To the extent feasible, Atlantic will minimize tree removal during construction. Cleared vegetation and stumps will be either burned, chipped (except in wetlands), or hauled offsite to a commercial disposal facility. Burning will be conducted in accordance with State and local burning requirements or permits in uplands; burning will not be conducted in wetlands. Atlantic Coast Pipeline 2 Nationwide Permit No. 12 — Pre -Construction Notification U.S. Army Corps of Engineers — Wilmington District Following clearing, the construction right-of-way and ATWS will be graded where necessary to provide a level work surface to allow safe passage of construction equipment and emergency vehicles. More extensive grading will be required in steep side slope or vertical areas and where necessary to prevent excessive bending of the pipelines. Graded topsoil will be segregated in accordance with the Plan and Procedures, where required. Typically, topsoil will be segregated from subsoil in cultivated and rotated croplands, managed pastures, residential areas, and hayfields, unless Atlantic is instructed by a landowner or land managing agency not to do so or Atlantic imports topsoil in accordance with the Plan. The depth of topsoil removed will depend on soil conditions and landowner requests or land managing agency requirements. In accordance with the Plan, and in areas where topsoil segregation is required, Atlantic will segregate at least 12 inches of topsoil in deep soils (more than 12 inches of topsoil) and the entire topsoil layer in shallow soils (less than 12 inches of topsoil). Excavated topsoil will be placed on the edge or edges of the construction right-of-way (See Pre -Construction Notification Application for Construction Typical Drawings — Appendix E) If the ground is relatively flat and does not require topsoil segregation or grading, the existing vegetative mat will be peeled and removed similar to topsoil and stockpiled along the right-of-way for use in restoration. In areas disturbed by grading, and as required by the Plan and Procedures, temporary erosion and sediment controls will be installed within the right-of- way to minimize erosion. The erosion and sediment controls will be inspected and maintained throughout the construction and restoration phases of the ACP, as appropriate, and as required by the Plan and Procedures. 1.1.3 Erosion Control Device Installation Atlantic will install temporary best management practices and/or erosion control devices (ECD), such as slope breakers, sediment barriers, stormwater diversions, etc., as necessary to prevent erosion within the construction right-of-way and ATWS immediately after the initial removal of vegetation (clearing and grubbing) and prior to grading and soil disturbance. ECDs will be installed in accordance with applicable permit conditions. The temporary ECDs will be replaced by permanent ECDs as installation of the pipeline and restoration is completed. ECDs and best management practices will be properly maintained throughout construction and reinstalled as necessary (such as after backfilling of the trench) until replaced by permanent erosion controls, or restoration of adjacent upland areas is complete, and revegetation has stabilized the disturbed area. 1.1.4 Trenching The pipe trench will be excavated by rotary trenching machines, track -mounted backhoes, or other similar equipment. Excavated material will be temporarily stored adjacent to the trench within the construction right-of-way. The trench for each pipeline will be excavated to a depth that provides sufficient cover over the pipeline after backfilling. The typical dimensions of each pipeline trench will vary depending on a number of factors, such as the diameter of the pipe being installed and the substrate in the vicinity of the trench. The bottom width of the trench will be sufficient to accommodate the diameter of the pipeline and sufficient Atlantic Coast Pipeline Nationwide Permit No. 12 — Pre -Construction Notification U.S. Army Corps of Engineers — Wilmington District pad material around it (typically approximately 1 foot on either side of the pipeline). The top width will vary to allow the sides of the trench to be adapted to local soil conditions at the time of construction. If trench dewatering is required within or off of the construction right-of-way, it will be conducted in accordance with the Plan and Procedures and applicable permits in a manner that will not cause erosion or result in silt -laden water flowing into a wetland or waterbody. In areas where topsoil segregation is required, subsoil from trench excavations will be placed adjacent to the topsoil in a separate pile to allow for proper restoration of the soil during backfilling and restoration. Gaps will be left between the topsoil and subsoil piles to prevent stormwater runoff from backing up or flooding. Mixing of topsoil and subsoil piles will be prevented by separating them physically or with a mulch or silt fence barrier, where necessary, to accommodate reduced workspace. When rock or rocky formations are encountered, tractor -mounted mechanical rippers or rock trenchers will be used for breaking up the rock prior to excavation. In areas where mechanical equipment or other means cannot be used to break up or loosen boulders or shallow bedrock, blasting will be required. 1.1.5 Pipe Stringing, Bending, and Welding Individual joints of pipe (up to 80 feet long) will be trucked to the construction right-of- way and strung along the trenchline in a single, continuous line. Individual sections of pipe will be bent, where necessary, to allow for a uniform fit with the contours at the bottom of the trench and horizontal points of inflection. Typically, a track -mounted, hydraulic pipe -bending machine will tailor the shape of the pipe to conform to the contours of the terrain. After the pipe sections are bent, they will be welded together into long sections and placed on temporary supports. Welding is a crucial phase of pipeline construction because the integrity of the pipeline depends on this process. Each weld must exhibit the same structural integrity with respect to strength and ductility. Welding will be conducted in compliance with 49 CFR 192 and API Standard 1104, Welding of Pipelines and Related Facilities. Completed welds will be visually and radiographically inspected. Welds that do not meet established specifications will be repaired or removed. Following welding and after inspection, pipe weld joints will be coated with an epoxy coating in accordance with required specifications. The coating will be inspected for defects, and repaired, if necessary, prior to lowering the pipe into the trench. 1.1.6 Lowering -in and Backfilling Prior to lowering -in, the trench will be inspected to confirm it is free of rocks and other debris that could damage the pipe or its protective coating. Dewatering may be necessary to inspect the bottom of the trench in areas where water has accumulated. If dewatering is required, it will be conducted in accordance with the Plan and Procedures and applicable permits in a manner that will not cause erosion or result in silt -laden water flowing into a wetland or waterbody. Atlantic Coast Pipeline 4 Nationwide Permit No. 12 — Pre -Construction Notification U.S. Army Corps of Engineers — Wilmington District The pipe will be lifted from the temporary supports and lowered into the trench using side -boom tractors. As necessary, trench breakers (stacked sand bags or foam) will be installed in the trench, around the pipe, to prevent movement of subsurface water along the pipeline. After lowering -in, the trench will be backfilled with previously excavated materials using bladed equipment or backhoes. If the excavated material is rocky, the pipeline will be protected with a rock shield or covered with other suitable fill. In appropriate circumstances, excavated rock may be crushed with a rock pulverizer and incorporated into fill or used as gravel to upgrade access roads. Excavated material that is not required for backfill will be removed and disposed of at approved disposal sites. 1.1.7 Hydrostatic Testing After backfilling and all other construction activities that could affect the pipeline are complete, each pipeline will be hydrostatically tested in sections to verify that each system is free from leaks and will provide the required margin of safety at operating pressures. Individual sections of pipeline to be tested will be determined by water availability and terrain conditions. Water for hydrostatic testing will be obtained from surface or groundwater sources in accordance with State regulations and required permits. As practicable, water will be transferred from one test section to another to reduce the amount of water that is required for testing. Once hydrostatic testing is complete, the test water will be discharged in accordance with the Plan and Procedures and applicable permits through an approved discharge structure to remove turbidity or suspended sediments (i.e., dirt left in the pipe during construction). Alternatively, the water will be hauled offsite for disposal at an approved location. During hydrostatic testing, internal pressures and durations will be in accordance with 49 CFR 192 and applicable permit conditions. If leaks are found during testing, the leaks will be repaired and the section of pipe retested until the required specifications are met. 1.1.8 Cleanup and Restoration Final cleanup will begin after backfilling and as soon as weather and site conditions permit, with the target of completing final cleanup (including final grading and installation of permanent erosion control devices) within timeframes required by permits, in accordance with landowner requests, or as required by the Plan and Procedures. Construction debris will be collected and taken to an approved disposal facility. Non -hazardous pipeline construction wastes include human waste, trash, pipe banding and spacers, waste from coating products, welding rods, timber skids, cleared vegetation, stumps and rock. Human waste is handled and disposed of exclusively by means of portable, self-contained toilets during all construction operations. All waste which contains (or at any time contained) oil, grease, solvents or other petroleum products falls within the scope of the oil and hazardous substances control, cleanup, and disposal procedures. This material will be segregated for handling and disposal as hazardous wastes. Pre -construction contours will be restored as closely as possible. Segregated topsoil will be spread over the surface of the right of way, and permanent erosion controls will be installed. Sand, foam, and/or cement trench breakers will be installed in the trench along the pipeline to prevent or slow the movement of water along the trench. Mechanically fastened erosion control blankets, in lieu of mulch, will be installed on steep slopes to stabilize vegetation. Grades in Atlantic Coast Pipeline 5 Nationwide Permit No. 12 — Pre -Construction Notification U.S. Army Corps of Engineers — Wilmington District excess of 3:1 will be stabilized with degradable blanket mulch such as jute mesh, wood excelsior or fibers until the vegetation is established. Permanent erosion control measures will include materials such as Flexterra as well as diversion ditches, water bars, check dams, and rock veneer with seeding. The material selected is dependent on the slope as well as the method chosen. Atlantic will employ best in class design and operational measures for construction in steep slopes (greater than 30 percent) to minimize or eliminate landslides during construction and operations. Dominion will hire licensed geotechnical professionals to provide input and review during the design, assessment and implementation of the best in class measures in steep slope portions of the project. Restoration of steep terrain may include: grading to the natural conditions; installation of permanent erosion control devices (i.e., slope breakers) designed to reduce runoff velocity and encourage retention of soils; and the use of additional structural materials (e.g., rock or woody debris) to provide an anchor for re -vegetation and deposition of soil. Revegetation measures will be implemented in accordance with the Plan and Procedures or as directed by the appropriate land managing agency. Disturbed, non -cultivated work areas will be stabilized and seeded as soon as possible after final grading, weather and soil conditions permitting, subject to the recommended seeding dates for the seed mixes used to revegetate different areas along the pipelines. Seeding will stabilize the soil, improve the appearance of the area disturbed by construction, and in some cases, restore native flora. On most pipeline projects, right-of-way reseeding mixes generally consist of grass species that grow well in the local area and that are effective in controlling soil erosion in areas that have been disturbed during construction of the pipeline. Seed mixes may also include species of grass that provide food and habitat for some wildlife. As part of Atlantic's Restoration and Rehabilitation Plan, Atlantic will incorporate regionally -specific and endemic forb (flowering plants) mixes in its traditionally all -grass seed mixes. The species of both grasses and forbs used on lands within the Monongahela and the George Washington National Forests will be selected based on consultation with each Forest. Both soil types and degree of slope will be considered in the selection of the seed mixes. Other factors to consider will be the introduction and control of woody species that may compete with the native forbs. The incorporation and development of native flowering plants could create, where conditions and land management practices along the pipeline corridor are suitable, substantial acreages of pollination habitat where this type of habitat is either currently non-existent or was previously degraded. Markers showing the location of the pipeline will be installed intermittently along the pipeline rights of way according to ACP and SHP specifications as well as at fence, road, and railroad crossings to identify DTI as the operator of the new pipelines. The markers will convey emergency information in accordance with applicable government regulations, including U.S. Department of Transportation safety requirements. Special markers providing information and guidance to aerial patrol pilots also will be installed. 1.1.9 Access Roads Atlantic has identified roads that will be used to provide access to the Project construction rights-of-way, permanent easement, and other facilities during construction and operation of the ACP. Atlantic will utilize existing roads to the extent practicable, but some new Atlantic Coast Pipeline 6 Nationwide Permit No. 12 — Pre -Construction Notification U.S. Army Corps of Engineers — Wilmington District roads may need to be built in remote areas. Additionally, new roads will need to be built to provide access to aboveground facility sites (i.e., compressor and Metering and Regulating stations, valves, and pig launcher/receiver assemblies) during operations. In some cases, existing roads will require improvement (such as grading, gravelling, replacing or installing culverts, minor widening, and/or clearing of overhead vegetation) to safely accommodate construction equipment and vehicles. A sufficient number of roads with regular spacing is needed to minimize congestion of construction vehicles and equipment on the right-of-way, which otherwise would increase the duration of construction and create unsafe work conditions for workers. If any existing roads are damaged during construction, Atlantic will restore these roads to preconstruction condition or better. Access road locations were identified based on the needs of construction and operations to provide sufficient ingress and egress to and from the proposed pipeline rights-of-way and aboveground facility sites. Impacts on wetlands and waterbodies will be avoided to the extent practicable by skirting wetlands or waterbodies, and where feasible necking down the access road. Along temporary access roads temporary timber construction mats, temporary bridges, culverts, or temporary rip rap will be utilized as a temporary means to stabilize access roads for use during construction. Permanent access roads however may require improvements, such as placement of culverts or widening of the roadbed that will remain in place for operation of the pipeline and associated facilities. Atlantic Coast Pipeline