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L& One soil sample was collected from beneath each UST at depths of 9 to 10 feet below ground surface (bgs) and analyzed for Total Extractable Petroleum Hydrocarbons (TEPH), Total Volatile Petroleum Hydrocarbons (TVPH), benzene, toluene, ethylbenzene and xylenes (BTEX), ethylene dibromide and total lead by Canonie Environmental Services Corporation. Laboratory results indicated that concentrations of petroleum hydrocarbons were detected in all three soil samples. Concentrations of petroleum hydrocarbons included 760 parts per million (ppm) TVPH beneath the center UST (Tank 2), 4,700 ppm TEPH from beneath the northern weed oil UST (Tank 1) and 4,800 ppm TEPH from beneath the southern weed oil UST (Tank 3). The soil APO sample analytical results are summarized in Table 1. 1,2.2 Environmental Site Investigations On January 23, 1998, Ramage Environmental published Site Investigation Report, which documented the soil and groundwater sampling and analysis from 11 Geoprobe® soil borings. The soil boring locations are shown on Figure 2, and the soil sample analytical results are summarized in Table 1. Field observation and analytical laboratory results indicated that diesel and gasoline +..� hydrocarbons had impacted soil and groundwater beneath the site, the city of Tracy right-of-way (Hamilton Alley) and other private property parcels to the north and east of the site. On January 27, 1999, Ramage Environmental published Monitoring Well Installation and Groundwater Sampling Report, which documented the installation of three groundwater table w monitoring wells (MW-1, MW-2 and MW-3). Only the groundwater sample collected from MW-2, northeast (down-gradient) of the former UST source area, contained a concentration of petroleum hydrocarbons above laboratory reporting limits. The sample from MW-2 contained only 140 micrograms per liter (4g/1) of Total Petroleum Hydrocarbons (TPH)-as-diesel. The well locations are shown on Figure 2, the well construction details and groundwater monitoring data 4.0 are summarized in Table 2, and the groundwater analytical results are summarized in Table 3. On February 18, 1999, the three monitoring wells were re-sampled, and none of the petroleum hydrocarbon compounds analyzed were detected above laboratory reporting limits. As a result, environmental corrective actions were discontinued at the site, but the case was never closed. r.. In January 2006, Ramage Environmental resumed quarterly groundwater monitoring, to re- v evaluate groundwater conditions beneath the site, so that the case could be considered for regulatory closure. Between January 2006 and August 28, 2008, Ramage Environmental monitored and sampled the three monitoring wells for 11 consecutive quarters. w, 5