2019-12-09-minutes-public-works-study-session

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CENTURY WEST. E N G I N E E R I N G E' S design analysis. Section 3 of this report provides a discussion of the circumstances that have changed since the original scope of work was approved. 2.1. LEVEL OF PRELIMINARY DESIGN The Proposed Action, Purpose and Need, and Alternatives task of the original scope included a subtask for preliminary design, which identified work elements required to get the project design to 25 percent completion but no further. The subtask included preliminary runway and taxiway layout and grading design per FAA standards, preliminary storm drainage design, a draft cost estimate, and preliminary 25 percent design plans. Topographic survey was conducted as part of the Proposed Action, Purposed and Need, and Alternatives task, but geotechnical investigation was not included in the original scope. 2.2. LIMITS OF ENVIRONMENTAL STUDY Within the original scope of work, the airfield flood mitigation component of the project necessitated the definition of two main study areas: the direct study area and the indirect study area. The direct study area was defined as, "an area which encompasses the entire construction footprint for airport improvements." The indirect study area was defined as, "an area which encompasses the entire Airport and off-site property to the north on which there is potential for floodplain related effects to nearby Mercer and Whiskey Creeks." The Environmental Permitting and Coordination task included subtasks for cultural resources survey, environmental inventory of threatened & endangered (federal and state) species, wetland delineation, and floodplain assessment. Airfield flood mitigations were initially expected to occur within the direct study area and off-site wetland mitigations were not anticipated to be required. Therefore, the cultural resources survey, environmental inventory, and wetland delineations were limited to the direct study area. The indirect study area was reserved for the floodplain assessment subtask. The original scope assumed that existing mapping resources, such as County maps and National Wetland Inventory (NWI) maps, accurately estimated the presence and general extent of wetlands on the airfield within the direct and indirect study areas. 2.3. PERMITTING SUBMITTALS The Environmental Permitting and Coordination task of the original scope included another subtask for preparation of required permit/consultation submittals. Permit applications and supporting documents were to be provided to the following agencies: + DEPARTMENT OF ARCHAEOLOGY AND HISTORIC PRESERVATION —Project description and graphics depiction of the area of potential effect (APE) and Cultural Resources Report. • TRIBAL CONTACTS— Project description and graphic depiction of the APE and Cultural Resources Survey/Report. • US ARMY CORPS OF ENGINEERS (CORPS); DEPARTMENT OF ECOLOGY (ECOLOGY); KITTITAS COUNTY— Wetlands Delineation Report, Mitigations Plan (if needed),.and Joint Aquatic Resources Permits Application (DARPA). If wetland impacts are encountered, it was anticipated a Nationwide Permit from the Corps and Ecology would be required and that a Critical Areas Permit from the County would be required. • KmrrmsCOUNTY — Floodplains Assessment Report, Floodplain Development Permit Application. Bowers Field Airport Environmental Assessment Page 2 Advanced Design Needs for NEPA Analysis November 27, 2019