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Habitat Assessment Conservation Measures 16 July 2019 4.2 Construction Process The replacement shoreline protection will be replaced approximately 20 feet section at a time. Unstable soil will be excavated and the bulkhead placed a minimum 1.5 feet below the bed of the beach. Colluvial and fill soils will be removed in order to place footing on a stable footing. Clearing of vegetation will be minimal and will only impact the lawn adjacent to the bulkhead. Suitable soil excavated for placement of the footing that contains coarse sand and gravels will be placed on the beach, as allowed by WDFW. No soils that contain clays or fine material will be placed below OHW. Bulkhead construction will occur during the allowed federal and state fish work windows. No work will occur when the area is tidally inundated. Materials and equipment will be brought in by barge and will operate within 25-feet of the existing shoreline protection. Existing stormwater tightlines, if present, will be integrated into the replacement shoreline protection. 4.2.1 Construction Schedule Construction activities will occur during daylight hours within the normal work week. In-water construction will take place during the low tide period when the project area is not inundated. In- water work will be conducted between July 16 and February 14, within the prescribed work windows as determined by WDFW and ACOE for juvenile salmon and forage fish species. All work will be completed within three weeks. 4.3 Conservation Measures The following protection and conservation measures will be followed by the bulkhead contractor. Any additional measures imposed by regulatory agencies will also be strictly followed. • Work below the ordinary high water line will not occur from February 15 through July 14 of any year for the protection of migrating juvenile salmon. • Work below the ordinary high water line from October 1 through April 30 of any year will be performed within forty−eight hours after the location is inspected by a department representative or biologist acceptable to the department and it is determined that no spawning is occurring or has recently occurred. • Project activities below MHHW will not occur when the project area, including the work corridor is inundated by tidal waters. • The existing concrete structure will be removed from the beach and disposed at an appropriate upland facility. July 2019 17 • The waterward face of the replacement concrete bulkhead will be located 1 foot landward of the existing structure. • All trenches, depressions, or holes created in the beach area will be backfilled prior to inundation by tidal waters. Trenches excavated for footings may remain open during construction. However, fish shall be prevented from entering such trenches. • All waste material such as construction debris, silt, excess dirt or overburden resulting from this project will be deposited above the limits of flood water in an approved upland disposal site. • All manmade debris on the beach will be removed and disposed of upland such that it does not enter waters of the state. • All natural habitat features on the beach larger than 12 inches in diameter, including trees, stumps, logs, and large rocks, will be retained on the beach following construction. These habitat features may be moved during construction if necessary. • Project activities will be conducted to minimize siltation of the beach area and bed. • Extreme care will be taken to ensure that no petroleum products, hydraulic fluid, fresh cement, sediments, sediment-laden water, chemicals, or any other toxic or deleterious materials are allowed to enter or leach into the beach or water. • Project activities shall not degrade water quality to the detriment of fish life. Chapter 5. Project Area’s Habitat 5.1 Types of Impacts 5.1.1 Direct Effects Bulkheads and bank protection can have numerous direct and indirect impacts on critical fish and wildlife habitat and species of concern (WDFW 2006). Directs effects are those impacts resulting from the proposed action. Direct impacts include elimination of habitat and disturbance to fish and wildlife caused by noise and water quality issues. The proposed action for this project is the replacement of the existing concrete bulkhead with an concrete bulkhead 1 foot landward. The proposed action includes both short and long term direct effects. Short term direct impacts include impacts from the construction activities. These impacts include removing landscaping vegetation associated with excavating landward of the existing bulkhead to place footings, operating the excavator within the authorized work corridor, and the temporary grounding of the barge. 32 July 2019 oceanic habitats. Relevant assessment of EFH at the proposed project area includes intertidal/nearshore and associated riparian areas. The proposed replacement shoreline protection project includes the removal of an existing concrete shoreline protection structure previously built within potential sand lance and surf smelt spawning gravel. The proposed replacement shoreline protection will continue to protect the marine shoreline from wind and wave action. Placement of the concrete bulkhead will prevent future erosion. The shoreline protection project may temporarily reduce the populations of benthic organisms in a small area adjacent to the project that are prey species for various groundfish and juvenile pelagic fishes that utilize intertidal/nearshore EFH. Benthic and epibenthic prey species that are temporarily displaced are expected to recover quickly after construction activities are completed. Since new invertebrate communities will quickly reestablished in the project areas, no long-term loss of biological productivity is expected as a result of the shoreline protection project. Similarly, forage species such as surf smelt, sand lance, and squid could also be temporarily impacted by elevated temporary turbidity. However, the impacts are expected to be minor because the species are not expected to be in the project area during construction. In order to conserve intertidal/nearshore EFH and reduce potential effects on associated species, the proposed shoreline protection project would incorporate the following conservation measures: • Project activities will be limited to replacement of existing shoreline protection only. • No additional elimination of intertidal habitat will occur. • Work below the ordinary high water line will not occur from February 15 through July 15 of any year for the protection of migrating juvenile salmonids. • A forage fish spawning survey, by a qualified biologist, will take place before construction begins to ensure that no eggs are present adjacent to the project site, as required by WDFW. • Project activities below MHHW will not occur when the project area, including the work corridor is inundated by tidal waters. • Use of equipment on the beach will be held to a minimum, confined to a single access point, and limited to a 25-foot work corridor waterward of the existing bulkhead. • All trenches, depressions, or holes created in the beach area will be backfilled prior to inundation by tidal waters. If trenches excavated for the footings need to remain open during construction, fish will be prevented from entering such trenches. July 2019 33 • All waste material such as construction debris, silt, excess dirt or overburden resulting from this project will be deposited above the limits of flood water in an approved upland disposal site. • All manmade debris on the beach will be removed and disposed of upland such that it does not enter waters of the state. This includes the pre-existing pieces of concrete and anthropomorphic debris. • Intertidal wetland vascular plants will not be adversely impacted due to project activities (e.g., barge shall not ground, equipment shall not operate, and other activities shall not occur in intertidal wetland vascular plants). • Project activities will be conducted to minimize siltation of the beach area and bed. The project shall not degrade water quality to the detriment of fish life. The combination of the conservation measures detailed above and the temporary and localized affect of project activities reduces the effects on Essential Fish Habitat to the point that the effects will be insignificant and discountable, and thus the proposed shoreline protection project May Affect, but is Not Likely to Adversely Affect Essential Fish Habitat. 5.4 Assessment Report Conclusion The purpose of the preceding Floodplain Habitat Assessment Report is to document that the proposed project meets the requirements and criteria of the Endangered Species Act (ESA) as clarified in the Biological Opinion issued by the National Marine Fisheries Service (NMFS) on September 22, 2008. This Floodplain Habitat Assessment Report concludes, that with minimization and conservation measurements, the following: • No Affect or May Affect, but is Not Likely to Adversely Affect Endangered Species • May Affect, but is Not Likely to Adversely Affect Essential Fish Habitat 6.0 References Boehlert, G.W. 1980. Size composition, age composition, and growth of canary rockfish, Sebastes pinniger, and splitnose rockfish, S. diploproa, from the 1977 rockfish survey. Mar. Fish. Rev. 42:57–63. Calambokidis, J. and G. Steiger. (1990). Sightings and Movement of Humpback Whales in Puget Sound, Washington. Northwestern Naturalist 71:45-49. Autumn 1990.