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feet bgs), TPH gasoline and BTEX were not detected above laboratory reporting limits in the soil or groundwater samples. On May 18, 2000, the UST and 118 cubic yards.of soil around the UST were excavated and removed. Analytical results from UST excavation confirmation soil and stockpile soil samples indicated that petroleum hydrocarbons were not detected above laboratory reporting limits. On June 22; 2000 three borings were advanced and wells MW-1 through MW-3 were installed in each boring to 15 feet bgs. Soil samples:from a depth of 6 feet bgs from each boring were submitted for analyses. TPH gasoline (1,100 ug/kg) and xylenes (88 ug/kg) were detected in MW-1, and MTBE (250 and 17 ug/kg) was detected in MW-1 and MW-2. Petroleum hydrocarbons were not detected in the soil sample from MW-3. On April 1, 2004 a boring was advanced and well MW-4 was installed in the boring to 35 feet bgs. To evaluate potential vertical migration of petroleum hydrocarbons, MW-4-was installed in a deeper groundwater zone than the previously installed wells. Soil samples '. from depths of 25.5, 30.5, and 36 feet bgs were submitted for analyses. TPH gasoline, VOCs, and the five fuel oxygenates were not detected-above laboratory reporting limits in the three soil samples. Seven groundwater monitoring events have been performed between June 2000 and January .2005. During the first monitoring event; TPH gasoline, BTEX, MTBE, and TAME were detected in downgradient well MW-1; benzene, total xylenes, and MTBE were detected in MW-2; and MTBE was detected in MW-3. During the second monitoring event performed in October 2000 (approximately five months after removing the .UST), petroleum hydrocarbon concentrations in the groundwater significantly I decreased, most significantly in downgradient well. MW-1. MTBE was the ,only constituent detected in MW-1 and MW-2. Petroleum hydrocarbons were not detected above laboratory reporting limits in MW-3. Groundwater monitoring did not occur again until April 2004. Four consecutive quarterly monitoring events were performed between April 2004 and January 2005. Beyond a single detection of total xylenes at 1.1 ug/L in MW-2 during the April 2004 sampling event, MTBE was the only constituent detected in the groundwater samples since June 2000. On June 30, 2005 Kleinfelder submitted a request for No Further Action report to SJCEHD. Upon review of the report, SJCEHD granted the request for No Further € Action and site closure. In a letter dated September 7, 2005, the California Regional Water Quality Control Board concurred with SJCEHD. Both agencies require destruction of the four groundwater monitoring wells prior to granting case closure. 02301 PROP/SAC5P435 Page 2 of 5 September 30, 2005