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GRANITE CONSTRUCTION COMPANY TRACY EXCAVATION EXPANSION PAGE 3 The project site has been extensively modified (disturbed) in the past. The middle portion of the project site, approximately one third of the property, was mined prior to Granite's acquisition of the site during historic mining. All topsoils and subsoils were removed from this portion of the project site. Other disturbances include extensive compaction from past mineral mining at an on-site mineral processing plant (since removed), overgrazing, establishment of the railroad grade right-of-way and spur, installation of an underground Unocal pipeline and creation and maintenance of facility access roads. In addition, the Corral Hollow Creek drainage which flows west to east across the project site was re-aligned and reconstructed adjacent to the California Aqueduct at the time of California Aqueduct construction in the 1960's. All existing site features are illustrated on DWG 1, Site Plan. There have been seven previous excavation permits authorized by San Joaquin County on this property: EP-71 (1966), EP-98 (1967), EP-136 (1968), EP-173 (1969), EP-71-13 (1971), EP-75-2 (1975), EP-80-3 (1979). The proposed expansion site was permitted under EP-80-3 (phases 3 and 4) to remove 30,000,000 tons of sand and gravel over a five-year period. An environmental impact report, ER-75-2 was prepared for Permit No. EP-75-2. The proposed expansion site was deleted from the QX-89-1 application(which was a renewal of EP-80-3) because of potential impacts to kit fox. QX-89-1 was subsequently approved, effective April 30, 1992, without phases 3 and 4 (the proposed expansion site). B. GEOLOGY The site is comprised of Sectors A-1n, A-lo, and A-lp as identified by the Department of Conservation, Division of Mines and Geology (DMG) as a Mineral Resource Zone (MRZ) of regional significance. The general composition of Sector A-1 is 55 percent gravel, 30 percent sand, 15 percent silt/clay, which is consistent with its location at the apex of the fan where coarse material has been deposited by Corral Hollow Creek. The site lies entirely within the Corral Hollow Creek Alluvial Fan, South of Tracy. (See DMG Aggregate Resource Sector Map and Special Report 160 excerpt attached).