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22 October 2009 AGE-NC Project No. 00-0697 Page 3 of 10 have been inferred towards the north,west,southwest and east; local ground water flow patterns at the site have been somewhat erratic.Ground water is considered to be of beneficial use and is used for domestic, industrial and commercial purposes. 2.2. UNDERGROUND STORAGE TANK REMOVAL On 27 April 1988,two 550-gallon leaded and unleaded gasoline USTs were removed from the site by Mr. Jacobs. The approximate locations of the former USTs are shown in Figure 2. Following removal of the USTs,representative soil samples was collected beneath the former leaded UST (RI) and the former unleaded UST location(U 1).The soil samples were collected at depths of 4 feet bsg and analyzed for total petroleum hydrocarbons quantified as gasoline(TPH-g)and volatile aromatic compounds benzene,toluene,and total xylenes.The soil sample collected from beneath the former leaded gasoline UST was also analyzed for ethylene dibromide(EDB)and total lead. Laboratory analysis of the RI soil sample detected TPH-g at a concentration of 570 milligrams per kilogram (mg/kg), toluene was reported at a concentration of 84 mg/kg, and total xylenes were reported at a concentration of 250 mg/kg.Benzene was not reported in either soil sample submitted for analysis. Analytical results of UST soil samples are summarized in Table 1;UST removal soil sample locations are depicted in Figure 2. 2.3. SITE INVESTIGATIONS The following is a brief summary of the site assessment investigations conducted at the site to date: • On 22 March 2000,four soil borings(B 1 through 134)were advanced at the site to depths of 30 feet bsg for collection of soil and ground water samples. Laboratory analysis of soil samples detected TPH-g from B2 at 10 feet bsg at a concentration of 14 mg/kg.Laboratory analysis of ground water samples detected from B1 and B2 at concentrations of 120,000 micrograms per liter (µg/1) and 15,000 µg/1, respectively, benzene, toluene, ethylbenzene, and total xylenes (BTEX) were reported at concentrations as high as 56,000 µg/1 xylenes (B1). Analytical results of soil and grab ground water samples are summarized in Tables 1 and 2.Boring logs are presented in Appendix C.A report of findings (Preliminary Investigation and Evaluation Report, dated 17 April 2000)was prepared by AGE and submitted to the EHD and RWQCB. • On 01 November 2004, four ground water monitoring wells(MW-1 through MW4)were installed at the site to depths of 25 feet bsg. Laboratory analysis of soil samples detected TPH-g from boring MW-3(MW3-10 and MW3-15)at concentrations of 5.2 mg/kg and 1.5 mg/kg, respectively. BTEX compounds were reported in the sarne samples at maximum Adwncrd Gef£mvir"s W,Le.