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Consistent with previous quarterly groundwater analytical results, the highest concentrations of gasoline compounds were detected in the sample collected from MW-1: 63.1 micrograms per liter (µg11) of TPH-as-gasoline, 2.0 µg/I of benzene, 0.9 µg/l of ethylbenzene, 2.9 µg/l of xylenes, and 1.8 µg/I of MTBE. Only MTBE was detected in MW-2 at 1.5 µg/I and in MW-3 at 0.9 µg/1. The ••• groundwater sample analytical results are summarized in Table 2, the distribution of gasoline in groundwater is shown on Figure 5, and the laboratory reports are included in Appendix B. Between December 13, 2006 and March 1, 2007, the distribution and concentration of gasoline compounds in groundwater remained relatively consistent. Concentrations of gasoline compounds in groundwater at MW-1 have generally declined, since the monitoring wells were installed in July 2002, probably due to source removal efforts and natural attenuation processes. Since March 2004, concentrations of MTBE have been detected in the perimeter wells (MW-2 and MW-3). During the first quarter of 2007, the MTBE concentrations detected in all three wells were below the state of California Secondary Maximum Contaminant Level (MCL) of 5 µg/l. V 2.3 Wastewater Disposal On April 4, 2007, Doulos Environmental, Inc. transported approximately 55 gallons of groundwater, accumulated from sampling activities as non-hazardous waste, to InStrat, Inc. in Rio Vista, California. InStrat treated the wastewater with granular activated carbon and disposed of it according to their waste discharge permit. A copy of the non-hazardous water transport form is included in Appendix C. 2.4 Investigation-Derived Waste Disposal On January 13, 2007, Ramage Environmental contained the waste soil and water generated from site investigation drilling into one, 55-gallon drum, pending waste characterization, landfill profiling r and proper disposition. Based on the investigation soil and groundwater sample analytical results, EnviroPacific profiled the drum of mixed waste for disposal at Norcal Waste Systems Hay Road Landfill (landfill) in Vacaville, California, under Authorization#3865. On April 23, 2007, EnviroPacific loaded the drum of waste soil onto a truck, and transported it as non-hazardous waste to the landfill for disposal. The non-hazardous waste manifest is included in Appendix C. 8