Exhibit KR-90 in Kern River Gas Transmission Company's proceeding under RP04-274: Summary of Unadjusted and Adjusted Billing Determinants Report.

ENVIRONMENTAL ANALYSIS CHAPTER 3 3.1 Geology 3.0 ENVIRONMENTAL ANALYSIS 3.1 Geology 3.1.1 Geology and Physiography The proposed EPP route would cross parts of three major physiographic provinces: the Wyoming Basin Province, the Southern Rocky Mountains Province, and the Great Plains Province (Fenneman and Johnson 1946; USGS 1985). The Wyoming Basin Province and Southern Rocky Mountain provinces generally consist of mountain ranges separated by broad basins, while the Great Plains Province is a remnant fluvial plain. Table 3.1-1 summarizes by MP the physiographic province, section, and geology along the proposed pipeline route. Construction of the proposed project facilities would not materially alter the geologic and physiographic conditions or worsen existing unfavorable geologic conditions in the area. Construction effects would include disturbances to the natural topography along the ROW and aboveground facilities due to grading and trenching activities. Upon completion of construction, Entrega would restore topographic contours and drainage patterns as closely as possible to their pre-construction condition. Operation of the pipeline and its associated facilities would not affect the geologic and physiographic conditions in the project area. 3.1.2 Mineral Resources Potentially Exploitable Resources In Colorado, known oil and gas producing reservoirs underlay approximately 90 percent of the proposed pipeline route and aboveground facilities and approximately 45 percent of the proposed project lies within an area of known oil shale-bearing strata in the Piceance Basin. Coal-bearing formations that are potentially mineable (both surficial and sub-surface sources) would underlay approximately 60 percent of the proposed pipeline route through Colorado, in Rio Blanco and Moffat Counties (Colorado Division of Minerals and Geology 2003). These areas also are potentially capable of producing economic quantities of coal-bed methane (EPA 2002). In Wyoming, approximately 80 percent of the EPP in Wyoming would occur in sedimentary basins with known oil and gas producing regions. Producing fields in those regions are clustered around the proposed Wamsutter Compressor Station in Sweetwater and Carbon Counties. Other producing fields lie near the proposed project in the Laramie Basin, in western Albany County (De Bruin 2002). Approximately 22 percent of the proposed route would lie within an area of known oil shale-bearing strata extending from the Wyoming-Colorado border north to Wamsutter, in the Washakie Basin. Approximately 60 percent of the proposed pipeline route would cross surface and subsurface coal-bearing formations that are potentially mineable in the Green River, Hanna and Rock Creek Coal Fields of Sweetwater, Carbon, and Albany Counties (Glass and Roberts 1980; Jones 1991; Case et al. 1998a). Typically, the pipeline trench would be about 6 to 7 feet deep to account ...