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<br />~~ <br />2.2 ENVIRONMENTAL SETTING AND SITE RECONNAISSANCE <br />According to the geologic map of Colorado, the bedrock geology of the site consists of the <br />Ogallala Formation which includes loose- to well-cemented sand and gravel. T'he surficial <br />geology consists of 0 to approximately 10 feet of eolian silt and fine sand over the Ogallala <br />Formation. In general, the site slopes to the northwest and is transected by two minor drainages, <br />one on the east boundary of the site and the other near the west boundary of the site. Between <br />these two drainages lies a small gently sloping, northwest trending ridge (dune). Both drainages <br />converge near the north boundary of the site to form a closed basin at the location of a past <br />gravel pit. The ground surface elevation of the site is approximately 3990 feet above sea level. <br />Based on surface topography, the site ground water flow is estimated to be north-northwest, and <br />the regional ground water flow is estimated to be to the east. Depth to groundwater is <br />approximately 75 feet below the ground surface. <br />A site reconnaissance was performed by GEI personnel on January 21, 1994 to observe surface <br />conditions which could indicate the presence of hazardous waste and/or oil. The weather at the <br />time of the site visit was clear with a temperature in the mid 50's. The reconnaissance included <br />walking the boundaries of the proposed ]ease area, which had been staked eazlier that morning <br />by Mr. Earnest Wolcott of Fisher Industries, and several random traverses. The:re was no <br />evidence of storage or use of hazardous materials or oil on the site. There was no snow cover <br />at the time and no vegetative distress was observed. <br />Currently, the land is mostly vegetated with native range grasses. Three areas of disturbance <br />were identified as test pits by Fisher Industries personnel. These test pits were excavated and <br />backfilled by Fisher Industries to evaluate the subsurface materials. A small topographic <br />depression and windmill-driven well are located neaz the southwest central part of the: site. This <br />windmill-driven well is pre-1967 based on the County photos and is used to water cattle. A past <br />aggregate pit is located near the northern portion of the site and consists of a 400-foot-long, 12- <br />to 15-foot near vertical cut slope in the sloping ridge in the middle of the site. Based on the <br />appearance of the vegetation around the pit, it does no appear that this pit has been used for quite <br />sometime. A separate smaller pit is located along the western boundary of the site. This pit is <br />approximately three feet deep, 50 feet wide and 200 feet long. Minor surficial iron staining of <br />the soil approximately 30 feet west of the large existing pit was observed during ou:r site visit. <br />This staining was limited to an area approximately two square feet and did not appear to <br />penetrate the subsurface materials more than a few inches. <br />910IZ~BNLLING.MW 3 <br />