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DESCRIPTION <br /> 9. Mineral commodity to <br /> be mined: rock and sand <br /> 10. Geologic Description - Briefly describe the general geologic <br /> setting, with more detailed geologic description of mineral <br /> deposit to be mined, and principal soil or rock types present <br /> KRC-Aggregate's (KRC) sand and gravel deposit is situated in <br /> * the gently rolling foot hills of the Sierra Nevada Mountains, <br /> which are located east of the Property. West of the Property <br /> lies the Great Central Valley of California, a major agricul- <br /> tural producing region. In this area are flat-lying conti- <br /> nental sediments which dip slightly to the west and overlie <br /> steeply dipping metamorphic rocks. No known earthquake <br /> faults exist on or near the site. <br /> Exploratory borings encountered the Turlock Lake Formation <br /> and the Laguna Formation. The Turlock <br /> Lake Formation is <br /> Pleistocene Age arkosic alluvium consisting of mostly fine <br /> sand, silt, and clay, with some pebbles of granitic and <br /> metamorphic rock. The Turlock Lake Formation is typically <br /> reddish brown in color and contains a high percentage (20% to <br /> 40%) of silt and clay. It was generally encountered in the <br /> upper 5 to 10 feet of the borings located east of Cord Road. <br /> The Laguna Formation is Pliocene Age arkosic glacial meltwa- <br /> ter alluvium consisting of sand, silt, and gravel of quartz <br /> and metamorphic rock. The Laguna Formation is stratigraphi- <br /> r tally located beneath the Turlock Lake Formation. KRC' s sand <br /> and gravel deposits are included in . the Laguna Formation. <br /> Underlying the Laguna is the Tertiary-age Mehrten Formation. <br /> The Mehrten Formation consists of well-rounded andesitic <br /> conglomerate, sandstone, siltstone and claystone of nonmarine <br /> typically fluvial origins. The units are stratified, but <br /> discontinuous over large areas, with cut and fill channeling. <br /> Mudflow deposits derived from the Sierra Nevada occur as <br /> interbeds. <br /> The principal source of the Laguna Formation sediments is <br /> eroded metamorphic rocks. They are thought to have been <br /> derived from metamorphics in the Sierra Nevada Mountains to <br /> the east by glacial erosion and washed to their present <br /> location by glacial melt water. Pebbles and cobbles of the <br /> Laguna Formation are highly siliceous metamorphic quartzite <br /> which are extremely tough and very durable. Finer fractions <br /> of the Laguna Formation include sand, silt and clays. <br /> 3 � <br /> �f. <br /> ii <br /> I <br /> KRC Aggregate, Inc. <br /> I - 2 - April 1, 1994 <br /> I <br />