SITE INFORMATION AND CORRESPONDENCE

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KLEINFELDER File No. 20-3978-01.W10 June 12, 1997 Mr. Donald Schuder of the California Department of Water Resources was contacted for information regarding on site wells. Available well logs were searched for records of wells at the Spreckels site. Copies of the geologic logs for the four monitoring wells installed on site by Ken Schmidt were located. Copies of these logs were not made because they are included in the copy of the monitoring well installation report provided by Spreckels Development. Mr. Schuder was unable to locate additional well logs for the site. Mr. Schuder indicated that this does not mean that no water wells are located on the property, only that he could not locate copies of well logs. Review of the 1985 and 1993 Ken Schmidt reports indicates that five water supply wells (designated 2A, 4, 5, 6A and 7), one livestock well and one domestic well are located on site. The 1985 Ken Schmidt report also describes the chemical composition of water from the water supply wells on site. The groundwater was classified as a calcium-magnesium-bicarbonate type water. Mr. Schmidt indicated that the water contained concentrations of iron above the California Maximum Contaminant Level (MCL). The water was characterized as having high hardness. Barium was detected in the wells at concentrations below the MCL. Nitrate concentrations in three of the wells sampled were above the MCL. Concentrations of arsenic above the MCL and elevated concentrations of manganese have been detected in the monitoring wells on site. The general direction of groundwater flow in the area of the site, based on a report issued by the San Joaquin County Flood Control and Water Conservation District, Spring 1995, is to the northwest. The elevation of first groundwater is approximately 20 feet above mean sea level. According to the same report, the depth to groundwater in the vicinity of the project site is approximately 20 feet below grade. During a November 19, 1996 monitoring event of the five Spreckels monitoring wells (MW-1 through MW-5) groundwater was found to exist beneath the site at a depth of approximately 10 to 15 feet. A groundwater gradient and direction was calculated based on depth-to-water data collected from these five and by data collected during a survey by RLC Associates on in December 1996. The groundwater flow direction is estimated to be towards the northwest at a relatively flat gradient of approximately 0.002 ft/ft. In areas of flat groundwater gradients such as this site, groundwater flow directions may significantly fluctuate due to rainfall, groundwater recharge, groundwater pumping, etc.. Therefore, changes in groundwater flow directions may vary at this site with time. 10-3978-OLW10/1017L155 Page 5 of 44 Copyright 1997, Kleinfelder, Inc.