The Commonwealth of Massachusetts Executive Office of Energy and Environmental Affairs 100 Cambridge Street, Suite 900 Boston, MA 02114 Charles D. Baker GOVERNOR Karyn E. Polito LIEUTENANT GOVERNOR Tel: (617) 626-1000 Kathleen A. Theoharides Fax: (617) 626-1181 SECRETARY http://www.mass.gov/eea June 25, 2021 CERTIFICATE OF THE SECRETARY OF ENERGY AND ENVIRONMENTAL AFFAIRS ON THE DRAFT ENVIRONMENTAL IMPACT REPORT PROJECT NAME : Vineyard Wind Connector 2 PROJECT MUNICIPALITY : Barnstable, Edgartown, Mashpee and Nantucket PROJECT WATERSHED : Cape and Islands EEA NUMBER : 16231 PROJECT PROPONENT : Vineyard Wind LLC DATE NOTICED IN MONITOR : April 7, 2021 Pursuant to the Massachusetts Environmental Policy Act (MEPA; M.G.L. c. 30, ss. 61- 62I) and Section 11.08 of the MEPA regulations (301 CMR 11.00), I have reviewed the Draft Environmental Impact Report (DEIR) and hereby determine that it adequately and properly complies with MEPA and its implementing regulations. The Proponent may prepare and submit for review a Final Environmental Impact Report (FEIR). The project is a component of an 800-megawatt (MW) wind energy generating facility known as Park City Wind (PCW) to be constructed approximately 19 miles south of Martha’s Vineyard. The generating facility will occupy a section of the Proponent’s 261-square mile (166,866 acres) Lease Area designated as OCS-A 0501 that was awarded to the Proponent through a competitive lease sale conducted by the federal Bureau of Ocean Energy Management (BOEM). The Proponent plans to construct three wind generating facilities in the OCS-A 0501 lease area. The first, known as Vineyard Wind, is located in the northern part of the lease area; components of the transmission infrastructure associated with the Vineyard Wind project, known as the Vineyard Wind Connector 1 (VWC1) completed MEPA review in 2019 (EEA #15787). The PCW project and a third project will be located in the Southern Wind Development Area (SWDA) occupying the southern part of the OCS-A 0501 lease area. The PCW project is being developed in response to a solicitation for a commercial-scale wind project by the Connecticut Department of Energy and Environmental Protection, but will utilize a cable corridor in EEA# 16231 DEIR Certificate June 25, 2021 Massachusetts state waters and make landfall in Barnstable, MA. According to the ENF, while the power from the project is being purchased by electric distribution companies in Connecticut, it will have a regional benefit by displacing fossil fuel-generated electricity in the electric grid operated by the Independent System Operator-New England (ISO-NE). The project will result in avoided emissions of 1.59 million tons per year (tpy) of carbon dioxide equivalent (CO2e), 850 tpy of oxides of nitrogen (NOx) and 450 tpy of sulfur dioxide (SO2). Major elements of the PCW project include a wind turbine array with 50 to 81 wind turbine generators (WTG) that each will have a generating capacity of 10 to 16 MW; offshore electrical service platforms (ESPs); inter-array cable connections between WTGs and ESPs; offshore export cables; onshore export cables; and an onshore substation. The offshore export cables will follow an approximately 63-mile long route from the WTG array to the landfall site at Craigville Beach in Barnstable. The components of the project located within Massachusetts state waters are known as the Vineyard Wind Connector 2 (VWC2), which is the project name used for purposes of state permitting within the Commonwealth. Project Description The DEIR expanded on the ENF to provide a more detailed description of project components. As described below, project components within the Commonwealth include approximately 23-mile long segments of the two offshore export cables, approximately four miles of onshore export cables in underground conduits and a new electrical substation. Offshore Export Cables Each 10-inch diameter offshore export cable will include a three-core 220-kilovolt (kV) or 275-kV alternating current (AC) cable and a fiber optic cable. The offshore export cables will be installed primarily in soft sediments using a trenching tool to create a 3.3-ft wide trench in which the cable will be buried to a depth of five to eight feet (1.5 to 2.5 meters) and covered with sediment. The offshore export cables will be typically installed at a rate of 100 meters (328 ft) to 200 meters (656 ft) per hour will occur 24 hours per day (approximately 1.5 miles to 3.0 miles per day). The cables will be separated from each other by a minimum of 165 ft (50 meters); the cable pair will be at least 330 ft (100 meters) west of the nearest VWC1 offshore export cable, a distance that may be even greater in deeper waters. According to the DEIR, the offshore export cables are anticipated to be installed primarily using a technique that simultaneously lays and buries the cable, such as a jet plow or mechanical plow. These trenching tools move along the seafloor on skids or tracks that are up to five feet wide. Cable installation will be done using vessels that pull the trenching tool and maintain position along the route by repositioning anchors. According to the DEIR, installation of an offshore export cable requires a dedicated complement of construction vessels; therefore, one cable will be installed at a time. Approximately two months prior to commencement of cable laying activities, a grapnel run will be made along the proposed cable route to clear obstructions, such as abandoned fishing gear and other marine debris. In areas where mobile sand waves are present on the ocean floor, the trench will be dredged using either a trailing suction hopper dredge (TSHD) or, for sand waves less than 6.6 ft high, jetting by controlled flow excavation. Sediment dredged using TSHD will be discharged onto a dredge barge, then released back into the water column in an area with sediments similar 2 EEA# 16231 DEIR Certificate June 25, 2021 to the dredged material. To adequately bury the cables in areas with large sand waves, the trench for each cable may be dredged with 3:1 side slopes and a bottom width of 50 ft. Where subsurface conditions prevent burial of the cable it will be placed on the seafloor and covered with protective armoring, which may include covered by rock, gabion rock bags, concrete mattresses or half-shell pipes. According to the DEIR, it is not anticipated that the VWC2 cable will cross over other cables along the route; however, some cable crossings may become necessary with other non-VW projects proposed along the same cable corridor, and in such instance, cable protection would also be required if a crossing is necessary. The offshore export cables will be installed within an Offshore Export Cable Corridor (OECC) that was identified through the results of marine surveys conducted by the Proponent in connection with the review and permitting of the VWC1 project. The DEIR described conditions within an expanded OECC based on additional surveys conducted in 2020. Compared to the OECC delineated for the VWC1 project, the OECC has been expanded by 985 ft (300 meters) to the west and by 985 ft to the east through a section of Muskeget Channel; however, the VWC2 offshore export cables will be installed entirely within the OECC as originally described and not within the expanded areas. As expanded, the OECC ranges in width from 3,100 ft to 5,100 ft along the portions located in Massachusetts state waters, with a typical width of 3,800 ft. The OECC follows a generally northerly route from the PCW turbine array to the landfall site. It enters state waters between Martha’s Vineyard and Nantucket near Muskeget Channel, veers to the east to avoid the deepest parts of Muskeget Channel where currents are strongest and important rocky benthic habitat is present, then turns west and follows a route parallel to the southeastern shoreline of Martha’s Vineyard and less than a mile from shore. Northeast of Martha’s Vineyard, an approximately six-mile long section of the OECC is located within a part of Nantucket Sound that is outside of State waters; it then follows a northeasterly route in State waters to the landfall site at Craigville Beach in Barnstable. Installation of the offshore export cables by trenching will stop approximately 1,000 feet from shore. Onshore Export Cables The export cables will be transitioned from the offshore environment to landfall at Craigville Beach through 1,000- to 1,200-ft long conduits located approximately 30 ft below the coastal surface. The conduits will be installed in a tunnel excavated using Horizontal Directional Drilling (HDD). The HDD construction technique involves excavation of a approach pit within the Craigville Beach parking lot, and drilling a one-inch to three-inch pilot hole from the approach pit, below the beach and other coastal wetland resource areas, to the offshore location where the cable trenching will terminate. After the pilot hole has been established, the end of the drill will be fitted with a cutter head and pulled back to the approach pit to create a hole of sufficient diameter for a conduit to be pulled through. Once the conduit is installed, the offshore export cables will be pulled through the conduit into an onshore underground vault, where the three conductors in each offshore export cable (a total of six conductors) will be separated. Activities associated with transitioning the offshore export cables onto land, including HDD operations, will take 15 weeks to complete. Each of the six onshore cables containing a conductor will be approximately six inches in diameter. The cables will be installed in a separate conduit within a buried concrete duct bank.