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capillary fringe at the time of drilling. Selected three samples for testing from the 50'boring. • Constructed monitor wells in each of the borings in conformance with the detail shown on the logs. The lower half of the shallow borings are screened (slotted). The 50'boring has only been screened in the lower 5 feet to assess lower-level groundwater conditions. 0 Following a grout cure period,the wells were developed by bailer surging and the removal of sediment laden water. The wells were then purged of three casing volumes of water. Development and purge waters have been placed in drums which have been sealed and labeled. The displaced water level was allowed to recover to within at least 80% and water samples were collected from the borings with new disposable bailers. • Six soil and four water samples have been submitted to a California-certified laboratory. The samples have been tested for gasoline, diesel, BTEX, 5 common oxygenates, and halogenated volatile organic compounds. Test methods have included the Mod EPA 8015,8010,8021,and 8260B methods. FINDINGS Soil Conditions observed during the drilling of each boring are presented on the attached boring logs. No obvious indication of soil contamination was observed during the drilling. However,the test data summarized on Table 1, indicate trace amounts of a few chlorinated solvents. The detected compounds include cis and trans dichloroethene as well as methylene chloride. It is relatively common to find these compounds utilized in a variety of industrial activities, including but no limited to degreasing and/or paint stripping. While none of the reported soil concentrations exceed EPA Preliminary Remediation Goals(PRGs),the tested soil samples were collected from near and/or within the groundwater zone which would suggest impact to the groundwater. Concentrations detected in the soil samples are summarized on Table 1 for convenience; the laboratory data are presented in the Appendix. Groundwater During drilling,saturated soils where generally noted at depths of approximately 15 feet, similar to earlier work at the site. During follow-up measurement of groundwater depths on May 28, 2004, static depths in Wells MW-1 through MW-4 measured 10.32', 10.65', 11.40',and 10.82',respectively. This would suggest a somewhat southerly gradient. Numerous buses in the yard the day of our water sampling rendered an elevation survey unfeasible; relative casing elevations would be determined during subsequent sampling episodes. Neither gasoline,diesel,nor oxygenates were detected in any of the water samples. Trace benzene was detected in MW-1 and MW-4 at concentrations of 0.62 and 0.58 parts-per-billion (ppb), respectively. Xylenes and trimethylbenzene were detected in MW-4 at the trace concentrations of Ramco n H:\WPDATA\1303-2-Anden;on\REPORTS\SumReport.wpd Page 3