The Commonwealth of Massachusetts Executive Office of Energy and Environmental Affairs 100 Cambridge Street, Suite 900
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The Commonwealth of Massachusetts Executive Office of Energy and Environmental Affairs 100 Cambridge Street, Suite 900 Boston, MA 02114 Charles D. Baker GOVERNOR Tel: (617) 626-1000 Karyn E. Polito Fax: (617) 626-1181 LIEUTENANT GOVERNOR http://www.mass.gov/envir Kathleen A. Theoharides SECRETARY June 26, 2020 CERTIFICATE OF THE SECRETARY OF ENERGY AND ENVIRONMENTAL AFFAIRS ON THE EXPANDED ENVIRONMENTAL NOTIFICATION FORM PROJECT NAME : Sucker Brook Continuity Restoration Project PROJECT MUNICIPALITY : Pepperell PROJECT WATERSHED : Nashua EEA NUMBER : 16208 PROJECT PROPONENT : Town of Pepperell Conservation Commission DATE NOTICED IN MONITOR : May 20, 2020 Pursuant to the Massachusetts Environmental Policy Act (M.G. L. c. 30, ss. 61-62I) and Section 11.03 of the MEPA regulations (301 CMR 11.00), this project is subject to the mandatory requirement to prepare an Environmental Impact Report (EIR). In accordance with Section 11.05(7) of the MEPA regulations, the Proponent submitted an Expanded Environmental Notification Form (EENF) with a request that I grant a Waiver of the requirement to prepare an EIR. In a separate Draft Record of Decision (DROD), also issued today, I propose to grant a Waiver of the EIR requirement. This Certificate sets forth the issues that must be addressed by the Proponent during permitting and discusses recommendations that were submitted on the project during the MEPA comment period. Project Description As described in the Expanded Environmental Notification Form (EENF), the project includes the removal of a stone dam that is not under the jurisdiction of the Office of Dam Safety (ODS) within the Department of Conservation and Recreation (DCR). The project also proposes to replace an undersized culvert located on Sucker Brook, a tributary to Nissitisset River. The purpose of the project is to restore continuity, restore sediment transport, and reduce elevated water temperatures in Sucker Brook in order to benefit native fisheries and wildlife including state-listed rare species. EEA# 16208 EENF Certificate June 26, 2020 The undersized culvert is located immediately upstream of the dam impoundment underneath the access road to the Keyes-Parker Conservation Area. The existing culvert will be replaced with two, side-by-side box culverts, each measuring 10 feet wide by 6 feet high (with the bottom two feet embedded beneath the natural stream bed) which will meet Massachusetts Stream Crossing Standards. The culverts will be placed on a concrete leveling pad to facilitate connection of culvert segments and to minimize the potential of differential settling. The twin culvert system will be equipped with headwalls, wingwalls, and associated footings. The excavation zone will be hydraulically isolated from the river using upstream and downstream coffer dams. River flow will be allowed to continue via gravity using a temporary bypass pipe to the river left side of the excavation area. Demolition of the stone dam will be primarily by hand with larger stones removed by small machine as necessary. The removal of the stone dam is anticipated to occur over a six to eight-week period which will allow the impoundment water level to be gradually drawn down over time. The gradual removal of the dam will minimize the amount of abrupt sediment migration that might occur. Approximately 4,500 cubic yards (cy) of sediment will be passively released as the dam is removed Stones and large woody debris salvaged from the dam will be reused in the vicinity of the dam site to create stream edge and in-channel reinforcement, energy dissipation, and aquatic habitat features. Some of the salvaged stones will also be used at the access road culvert site to provide similar in-channel reinforcement, energy dissipation, and aquatic habitat features. Project Site The project site is located within the Keyes-Parker Conservation area, an approximately 70-acre municipally-owned conservation area located off of Oak Street in Pepperell. The conservation area consists of approximately 60 acres of forested upland, 6 acres of meadow, and approximately 4 acres of wetland resources consisting of the 3.3-acre impoundment and associated wetlands. A beaver dam is located within the upper reaches of the impoundment. Sucker Brook flows in a south to north direction before joining the Nissitissit River approximately one mile downstream. The Nissitissit River flows into the Nashua River and eventually into the Merrimack River. The existing culvert located approximately 1,380 lf upstream of the dam consists of a 3-ft diameter reinforced concrete pipe (RCP) underneath the conservation area access drive. The culvert is equipped with a “beaver deceiver” which consists of a wire fence enclosure to prevent beavers from accessing the culvert. Because the enclosure tends to catch debris that blocks flow, most of the brook flow is carried by an approximately 18-inch diameter high density polyethylene (HDPE) pipe that conveys flow through the beaver deceiver. As described in the ENF, review of historic maps and aerial photographs indicates that the impoundment was formed by a stone dam which was likely constructed between 1936 and 1938. The dam is a run-of-the- river dam approximately 35 feet wide and constructed out of field stones. It creates a hydraulic drop of approximately four feet. Further to the river right (looking downstream), there is an approximately 6-foot-wide bypass channel. The main dam spillway regularly becomes blocked 2 EEA# 16208 EENF Certificate June 26, 2020 by woody debris and therefore a significant portion of the flow passes through the bypass channel during higher flow events. The project site is located within the Squannassit Area of Critical Environmental Concern (ACEC). The project site includes Natural Heritage and Endangered Species Program (NHESP) Priority and Estimated Habitat for rare species including the Brook Floater (Alasmidonta varicose), Creeper (Strophitus undulates) and Wood Turtle (Glyptemys Insculpta). Sucker Brook is classified as a Coldwater Fishery by the Division of Fisheries and Wildlife (DFW) and provides habitat for native eastern brook trout (Salvelinus fontinalis) and numerous other cold water fish species. Environmental Impacts and Mitigation This is an ecological restoration project designed to restore and enhance the natural functions of the brook and surrounding wetland resource areas, improve fish passage, and improve water quality. The project also has climate resiliency benefits, as it will reduce upstream flooding and roadway overtopping through the expansion of an existing culvert and dam removal. Due to the nature of the project, permanent conversion of wetland resource areas is unavoidable and temporary impacts associated with the construction period are anticipated. Potential environmental impacts associated with the project include the loss of approximately 271 linear feet of Bank; creation of 28,635 sf of Bordering Vegetated Wetlands (BVW); loss of 28,635 sf of Land Under Water (LUW) and loss of 710 sf of Riverfront Area. During the construction period, the project is anticipated to temporarily impact 530 lf of Bank; 5,035 sf of BVW, 22,065 sf of Riverfront Area. The project involves the passive release of approximately 4,500 cy of sediment. Measures to minimize construction period impacts include staging and maintenance of construction vehicles and equipment in designated areas, use of sedimentation and erosion control Best Management Practices (BMPs), and compliance with a habitat management plan approved by NHESP including Time-of-Year (TOY) restrictions (to be determined by NHESP). All disturbed areas will be stabilized and/or vegetated. Jurisdiction and Permitting The project is undergoing MEPA review and is subject to a mandatory EIR pursuant to 301 CMR 11.03(3)(a)(4) of the MEPA regulations because it requires State Agency Actions and will result in the structural alteration of an existing dam that causes any decrease in impoundment capacity. The project also exceeds the ENF thresholds at 11.03(3)(b)(1)(b), 11.03(3)(b)(1)(d) and 11.03(11)(b) because it involves the alteration of 500 or more linear feet of bank along a fish run or inland bank; alteration of 5,000 or more sf of bordering or isolated vegetated wetlands; and work located in an ACEC. The project requires a 401 Water Quality Certificate (WQC) and may require a Chapter 91 (c. 91) Permit from MassDEP. The project is receiving funding from the Division of Ecological Restoration (DER). The project will require an Order of Conditions (OOC) from the Pepperell Conservation Commission (or in the case of an appeal, a Superseding Order of Conditions from MassDEP) and submittal of a Pre-Construction Notification to the U.S. Army Corps of Engineers (ACOE) 3 EEA# 16208 EENF Certificate June 26, 2020 seeking authorization under the General Permits for Massachusetts in accordance with Section 404 of the federal Clean Water Act. Because the project is receiving Financial Assistance, MEPA jurisdiction is broad in scope and extends to all aspects of the project that may cause Damage to the Environment, as defined in the MEPA regulations. Request for EIR Waiver The Proponent submitted an EENF with a request that I waive the requirement for the preparation of a mandatory EIR, or if the Waiver is not granted (301 CMR 11.11), allow a Single EIR to be prepared in lieu of the usual two-stage Draft and Final EIR process pursuant to Section 11.06(8) of the MEPA regulations. The MEPA regulations at 301 CMR 11.11(1) state that I may waive any provision or requirement in 301 CMR 11.00 not specifically required by MEPA and may impose appropriate and relevant conditions or restrictions, provided that I find that strict compliance with the provision or requirement would: (a) result in an undue hardship for the Proponent, unless based on delay in compliance by the Proponent; and (b) not serve to avoid or minimize Damage to the Environment.