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located 4 112 miles to the east. The junction of Highways 12 and 88, the two major roadways in the area, is 2 miles to the east. GEOLOGIC & TOPOGRAHIC SETTING: The property is located on the eastern edge of the Sacramento Valley at an elevation of approximately 95 feet MSL; (Plate II. ) Aggregates are extracted from the various abandoned stream channels and tributaries of the Mokelumne River, which borders the property on the southeast. The regional gradient is to the west, but because of the irregularity of the terrain , it is difficult to determine the slope with any degree of accuracy. The Mokelumne River, which has its source in the Sierra Nevada Mountains to the east, and provides the source for the aggregrates bring mined, meanders in a general southwest direction and empties into the Delta area in the city of Stockton. SOIL CLASSIFICATION & PROFILE: According to the publication entitled "Soils of San Joaquin County California" issued by the Division of Soils of the University of California College of Agriculture, (1952, ) the soils in this area consist primarily of Columbia very fine sandy loam, Hanford sandy loam, Columbia clay loam, and Bear Creek clay loam. Plate IV is a composite ❑f maps • from that publication showing the general configuration of the various sail types. These soils are derived from recent alluvial fans or flood plain sediments; they have undeveloped profiles, and are generally underlain by uncolidated material . Storie indices vary from 54 to 85. Based upon the drillers log of the water well located on the property, the soil depth is about 6 feet, and is underlain by alternating beds of sands, cobbles, cemented gravels, and clays. Most of the property lies within the meandering watercourse of the Mokelumne River , whose discharge is now controlled by Comanche Dam. DEPTH TO GROUNDWATER: Based on static water level measurements taken from the water well located on the property, the water table has dropped from 90. 3 ' BGL in April 1976 to 99.5 ' EGL in November, 1988. County Flood Control District Maps also show yearly fluctuations in the area; the Spring 1983 map, (Plate V, ) indicates a depth of about 85 'BGL; exact surveyed elevations of the well or excavations are not available, but visual inspection of the property indicates that the water level measurements agree quite well when adjusted for differences in elevations. LOCATION OF WELLS: Plate VI shows the locations of water wells used for measuring depths to groundwater by the County Flood Control District. According to this map, there are no water wells within one ( 1) mile of this site. The water well on the property was drilled in 1956, and is used for plant operations 2