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• ~ -2- • According to my observations, this gravel pit site contains four main geologic divisions: 1) Gverburden Soils (Topsoils), 2) Gravelly Soils (Fineable Unit), 3) Weathered Shales (3edrock Unit) and 4) Alluvial Gravels (erosional Debris). 'Phe descriptions are as follows (please use in conjunction with the attached geologic map and cross-section): CVh'~SUnDL''ti SOILS (ToFSOils) Phis unit is shown by the orange area on the map, The topsoil in this area is very poorly developed and is only observed in a small area in the south- east :orner of the property (approximately 0.1 acre). These soils belong to the i•iesa Gravelly Clay Loam Group and are reddish yellow in color. The thickness ranges from one to three feet on this particular site. It contains some gravels, but not as much as the underlying gravelly unit (see Sample H-1 sieve data below), The gavels in this overburden unit range from cobbles to pebbles in size. The gravels that appear on the surface exhibit black desert varnish (manganese oxide) that is characteristic of grid regions. These soils are alkaline in nature and appear to be highly leached. The surface runoff of these soils is knorm to be intermediate in nature. The fines in this soil is made up of mainly silts and clays (the former appearing to be more prevalent). These soils seem to be poorly consolidated and only support sparse vegetation if any. G'%A'i~LL'L SOILS (Mineable Unit) This unit is shown by the yellow areas on the map. This unit forms the hard cap of the mesas of this area and outcrops exist towards the tops of both mesas on the gravel pit site. These soils also belong to the piesa Gravelly Clay Loam Group and are yellowish brown in color. The thickness on the site ranges from 2 feet in the far crest to 48 feet in the central part of the site--- the average thic`.tness being approximately 20 feet. According to the map, the lateral extent of this deposit is approximately 20 acres, The soils on the site exhibit properties very similar to the Mesa Gravelly Clay Loam type- section description, This soil unit is known to originate from old alluvium containing mainly igneous rocks and some sedimentary rocF:s (sandstones and shales). The organic content appears to be very low, About 50.E of the soil is made up of gravel ranging in size from cobbles to fine pebbles (see H-2 sieve sample data belcw). These gravels seem to be well-rounde3 and stratified in places. The gravels appear to be mainly of basaltic anal granitic composition. some gravels observed sere lime-encrusted. h:uch of the soil is cemented into semihardpan and hardpan, The permeability is }:norm to be intermediate to high