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sample tube was placed in a sealable plastic bag, disaggregated inside the bag to release any volatile organics that may be present and field-screened using a Photovac Microtip 1000 PID. PID readings were recorded on the boring logs. The monitoring well borings were drilled with a Simco 2400 drill rig equipped with continuous flight hollow stem augers. Soil samples were obtained using a 2-inch diameter by 18-inch long stainless steel California split spoon sampler lined with three (3) 2-inch diameter by 6-inch long brass sample liners. The sampler is driven into the soil by dropping a 40-pound weight on the sampler assembly from a height of 30 inches. The sampler is retrieved and the sample liners are extracted for collection and examination. The soil samples were collected, examined, logged and prepared by a California Registered Geologist. Soil descriptions were in accordance with the Unified Soil Classification System (USCS) as outlined in American Society of Testing Materials (ASTM) D2487. Logs of the borings are included in this report as Appendix VI. All coring tools and sample liners were decontaminated before and after coring each borehole to prevent cross contamination between boreholes using the following procedure: • Solids were removed from the coring and sampling equipment with a brush and washed in an Alconox-water solution. • Rinsing with tap water. ' 0 Rinsing with distilled water. 1 All collected soil samples were delivered in a chilled condition, with proper Chain of Custody, to Centrum Analytical Laboratories (Centrum) in Redlands, California. Centrum is a California Department of Health Services (DHS)- certified environmental laboratory (DHS ELAP Certificate No. 1184). 4.3 Monitoring Well Installation Procedures Groundwater was encountered during drilling at 30 feet b s in monitoring well ' MW2 and at 36 feet bgs in monitoring well MW3. The borings were deepened to 41 and 46 feet, respectively, which are at least 10 feet below the encountered groundwater level. Twenty (20) feet of 2-inch diameter PVC well screen with machine-slotted 0.01 inch openings were installed in each well in anticipation of ' the fluctuation of the water level due to seasonal changes. The well screen was topped with 2-inch diameter blank casing to 4 inches below ground surface level. ' The well screen and blank casing consist of flush-threaded, Schedule 40 PVC. CRC Environmental Risk Management,[ne. Project#2100-250-2 American Savings Bank 222 North El Dorado Street November 3, 1995 Stockton.California 6