Akutan Airport and Transportation Plan Reinitiation 2011
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Second Amendment To The BIOLOGICAL OPINION On the Effects of the Akutan Airport Project on Steller’s Eiders (Polysticta stelleri) and Northern Sea Otter (Enhydra lutris kenyoni) March 7, 2011 PURPOSE OF THE SECOND AMENDMENT To analyze the effects of proposed modifications to the Akutan Airport and Transportation Plan on Steller’s Eiders (Polysticta stelleri), Northern Sea Otters (Enhydra lutris kenyoni; hereafter “sea otter”), and sea otter critical habitat pursuant to section 7 of the Endangered Species Act of 1973 (16 U.S.C. 1531 et seq., as amended, ESA). DESCRIPTION OF THE PROPOSED ACTION The purpose of the project is to construct and operate airport facilities on Akun Island to serve the village of Akutan, and to provide passenger and freight service between Akun and Akutan via hovercraft. Facilities on Akun will include a runway, taxiway, apron, hovercraft landing ramp, an access road from the ramp to the airport, an equipment storage building, and aviation maintenance and support facilities. Activities on Akutan will include expansion of the existing seaplane ramp to provide a hovercraft passenger loading/unloading facility and construction of a hovercraft maintenance and storage facility at the head of Akutan Harbor. Construction will be conducted between March 8, 2011 and September 30, 2013. Airport construction and operation, which includes the operation of the hovercraft, are actions undertaken, funded and authorized by the Federal Aviation Administration (FAA) in cooperation with Alaska Department of Transportation and Public Facilities (DOT&PF) and the Aleutians East Borough. This project is the second amendment to the Biological Opinion on the Effects of the Akutan Airport Project on Steller’s Eiders and Northern Sea Otter (U.S. Fish and Wildlife Service 2007; consultation # 2007-0069; hereafter referred to as the BiOp). The first amendment (U.S. Fish and Wildlife Service 2010; consultation # 2007-0069-R001; hereafter referred to as the First Amendment) was issued July 30, 2010 and addressed two issues not covered by the BiOp: 1) impacts to critical habitat for the southwest Alaska Distinct Population Segment (DPS) of sea otters; and 2) issuance of an Incidental Harassment Authorization (IHA) for level B harassment of sea otters by the US Fish and Wildlife (FWS) Division of Marine Mammals Management (MMM) as authorized under section 101(a)(5) of the Marine Mammal Protection Act and/or its 1994 Amendments (MMPA). An IHA must be in effect before an Incidental Take Permit (ITP) can be issued for listed marine mammals that are also protected under the MMPA. An IHA was issued on July 14, 2010, and remains in effect until June 30, 2011 (Haskett 2010). 1 This second amendment to the BiOp addresses project impacts expected to result from newly- proposed changes to the original project. Thus, the complete amended BiOp shall include the original opinion (U.S. Fish and Wildlife Service 2007), the First Amendment (U.S. Fish and Wildlife Service 2010) and this second amendment; no single part should be considered independently from the others. Proposed modifications A detailed description of the airport proposal is contained in the BiOp and the Environmental Assessment for Akutan Airport Construction of a Land-Based Airport Akutan, Alaska (HDR Alaska, Inc. 2007). A Supplemental Environmental Assessment is in preparation by FAA to address proposed changes to the project that have come about during final design and design/build construction planning. Additionally, an addendum to the Biological Assessment was prepared and submitted to FWS (Houghton 2011). The proposed timeline for conducting construction activities has been modified. Construction may occur in March and November whereas previously, construction was scheduled for April to October. The design and construction plans for airport facilities have been modified. At Akutan, the existing 45 x 65-foot (0.07 acre) seaplane ramp will be will be expanded to a 100 x 110 feet (0.25 acres). No changes are proposed for the operation of the hovercraft or the hovercraft storage facility at the head of Akutan Harbor. All other proposed modification will affect Akun Island. The east end of the airport runway on Akun will be rotated counterclockwise 20° from the previously-proposed alignment (Figure 1). A segment of Stream #2 will be channelized and routed adjacent to the runway and a culvert will be installed to allow fish passage and cross- drainage beneath the runway. Additionally, a 330-foot long riprap berm will be constructed on the north side of the hovercraft landing pad to prevent Stream #1 from eroding the landing ramp. Temporary construction facilities will be installed, and will include a barge landing facility and access route along Surf Bay, a fuel storage facility, and a work pad and personnel camp. The barge landing facility will be constructed by grounding a barge in the tidelands to serve as an access platform for floating barge to load/offload materials. The grounded barge will connect to the beach with a ramp (Figure 2). A temporary access road will be routed between the barge landing facility and the hovercraft landing pad along the shore of Surf Beach below high tide line. Beach access will not require placement of fill material, but may require grading of existing surfaces along the access route. Two temporary bridges will be installed, one each across Stream #1 and Stream #2. A temporary gravel pad will be installed to provide stable ground for a personnel camp and work pad facility. The gravel pad will require placement of 1.1 acres of wetland fill. Geotextile fabric will be laid down prior to placement of fill and the area will be revegetated following construction. All temporary facilities will be removed and the affected areas restored as closely as possible to the pre-construction condition following completion of construction. 2 STATUS OF THE SPECIES and ENVIRONMENTAL BASELINE Status of the Steller’s eiders and sea otters within the action area and the factors affecting the species’ environment in the action area remain unchanged from that described in the BiOp and First Amendment. At least 716 (HDR Alaska, Inc. 2004) Steller’s eiders overwinter within the action area of the proposed project. We estimate that 10% of the birds within the action area may be using Surf Bay during winter. Therefore we estimate that 71 Steller’s eiders may be exposed to hovercraft disturbance each winter. Of those 71 birds, 1% (or 0.72 of a bird), rounded to 1 bird, is likely to be from the listed population. As described in the BiOp and First Amendment, up to 36 sea otters have been observed in one day in the action area (HDR Alaska, Inc. 2004) however, this area is larger than what is expected relative to the impacts of the hovercraft. It is estimated that 22 of these sea otters may occur within the buffer zone of the hovercraft’s operating route (HDR Alaska, Inc. 2006). EFFECTS OF THE ACTION and ANALYSES FOR EFFECTS OF THE ACTION Direct Effects Critical Habitat – The proposed modifications will result in an increased amount of fill to be deposited in sea otter critical habitat within Akutan Harbor and Surf Bay. The construction of a temporary barge landing area will resulting in temporary impacts to an estimated 0.3 acres of intertidal sea otter critical habitat. The expansion of the Akutan seaplane ramp will permanently impact 0.2 acres of sea otter critical habitat. Combined with the 1.1 acres of impacts described in the First Amendment, the total impact area is estimated to be approximately 1.6 acres. Indirect Effects Disturbance – The amount and effects of disturbance to sea otters is not expected to change from the assessment in the BiOp and First Amendment as a result of proposed modifications to the Akutan airport project. Overwintering Steller’s eiders in the area are likely to experience an increase in vessel traffic in March and November associated with the expanded construction season. However, these effects are temporary and are not anticipated to exceed the expected level of disturbance resulting from regular hovercraft operation occurring after construction is complete. This level of disturbance was analyzed in the BiOp and we do not expect an increase in the extent of harm beyond that which was predicted previously. Steller's eiders are known to forage and rest in the project area between November and March. The construction schedule has been expanded to include activities during the months of March and November. Potential disturbance from construction during these times was not assessed in the original BiOp or First Amendment. The expanded work season may increase the duration of exposure to disturbance, but will not affect any additional eiders. Impacts to Water Quality – The realignment of the airport runway will reduce distances between the hovercraft landing area and the runway, resulting in shorter road segments and less fill 3 needed in wetlands. Wetland fill will be reduced from 10.8 acres to 5.45 acres, but the potential for impacts to water quality will likely increase because the new runway alignment and associated facilities will be closer to Stream #1, Lake #1, and the marine environment (Figure 1). Shorter distance and more direct water flow into drainages will reduce the ability of the surrounding landscape to provide natural physical buffering and biological filtration of contaminated storm water discharged from the runway. Stream channelization will further speed the transport of contaminants, such as propylene glycol used as a runway deicer, from the airport facilities to the marine environment. Newly-proposed temporary construction facilities will increase the amount of expected soil disturbance and may contribute to release of contaminants into surface water. Potential contaminant sources associated with airport construction include fuels, oil, antifreeze, deicers, paints, fertilizers, human waste, sediments, and fertilizers.