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Vantage to Pomona Heights Chapter 3 230 kV Transmission Line Project FEIS Affected Environment PAGE 3-296 limited areas, many additional areas could experience an earthquake with forces capable of causing damage. This recommended practice should be used in all areas that may experience earthquakes. 3.15.3.4 2009 International Building Code Published by the International Code Council, the 2009 International Building Code (IBC) is used by the state of Washington and local jurisdictions. The purpose and subject matter of the IBC include comprehensive provisions regulating construction aspects of building and providing uniform standards for the purpose of protecting health, safety and general welfare. 3.15.3.5 Yakima Critical Areas Ordinance The Washington State Growth Management Act identifies Critical Areas. Critical areas established in each Washington State county in accordance with RCW 36.70A.170. The Yakima County Critical Areas Ordinance regulates geohazards within the county. Crossing of these areas in Yakima County may require a Critical Areas Permit. 3.15.3.6 Local Critical Areas In general, Benton, Grant, Kittitas, and Yakima counties identify geologically hazardous areas as local critical areas. These areas are addressed in Sections 3.15.2.2 and 3.15.4 of this document. Additionally, potential impacts to these areas are addressed in Section 4.15 of this document. 3.15.4 Route Segment Specific Considerations The study areas for geologic hazards for each route segment consisted of a six-mile wide study area (three miles on either side of the route segment centerlines). The study areas for soils characterization for each route segment consisted of a 500-foot wide study area (250 feet either side of the Action Alternative route segment centerlines). 3.15.4.1 Route Segment 1a/NNR-1 Route Segments 1a/NNR-1, 1b, and 1c are located on the western-most end of Yakima Ridge, an east- west trending anticline as shown on the Geohazards Map in Appendix A. Route Segment 1a/NNR-1 parallels Yakima Ridge along its northwestern foothills. The nearest identified fault trace lies approximately four miles away. While moderate-to-high liquefaction susceptibility lies along the Yakima River within a quarter mile of Pacific Power’s Pomona Heights Substation, the entire route segment is classified as extremely low to low. A few historic and/or quaternary landslide deposits lie within the six- mile study area, but not within the route segment. This route segment crosses five intermittent/ephemeral creek washes and geologic hazards are limited to those drainages. Route Segment 1a/NNR-1 corresponds to 137.2 acres of soils with high water erosion potential, 0.0 acres of soils with high wind erosion potential, and 60.4 acres of soils with low soil restoration potential. 3.15.4.2 Route Segment 1b Route Segment 1b continues along the northwestern foothills prior to turning south and traversing the Yakima Ridge. In addition to ephemeral creek washes, there are three landslides mapped along the route segment alignment along the northwestern foothills. Recent movement was not evident in aerial photography; however, to maintain the stability of these features, field review and determination of BMPs for this area would be prudent. Traversing Yakima Ridge, the route segment crosses an inactive thrust fault evidenced by exposed strata along the northern ridgeline. As the route segment continues to Route Segments 2a, 2b, and 2c along the southern foothills, ephemeral creek washes continue to pose a hazard. Route Segment 1b corresponds to 151.3 acres of soils with high water erosion potential, 0.0 acres of soils with high wind erosion potential, and 379.6 acres of soils with low soil restoration potential.