SITE INFORMATION AND CORRESPONDENCE

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1 . 02 . The propert*s surrounded on the east 0 the city sewer plant .' The area of the aboveground storage tank (AGT) is in the northeastern portion of the Property . The AGT is about 1 , 250 feet inside the property boundary. 1 . 03 . As detailed in the Paragraphs below, several site assessments , subsurface investigations, and groundwater investigations have been conducted at the Property. In general, total petroleum hydrocarbons (TPH) are present in soil and groundwater at the property. 1 . 04 . In November 1990 , a truck collided with a tank valve and caused the release of about 500 to 800 gallons of No. 6 fuel oil from a 420 , 000- gallon AGT in the northeast corner of the facility. 1 . 05 . In 1994 , under the oversight of Water Board- staff , ,Spreckels drilled seven soil borings around the existing AGTs . Soil samples were collected from six of the borings to a maximum depth of 14 feet below ground surface (bgs) , and .a grab groundwater sample was collected from the seventh boring. Maximum soil concentrations of TPH were in borings south and west of the Site . The maximum concentration of TPH was 7 , 300 milligrams per kilogram (mg/kg) at 0 . 5 feet bgs . The 10 . 5-foot bgs sample contained 3 , 900 mg/kg. No petroleum hydrocarbons were detected in the grab groundwater sample . 1 . 06 . In May 2002 , Spreckels drilled four soil borings southwest of the AGT. Soil samples were collected between six and 12 feet bgs . TPH as diesel (TPHd) and TPH as fuel oil (TPHfo) concentrations ranged from 44 to 1, 500 mg/kg and 55 to 2 , 200 mg/kg, respectively. Maximum concentrations were detected in the same boring south of the AGT between eight to 10 feet bgs . TPH groundwater concentrations ranged from 160 to 79, 000 micrograms per liter and 210 to 41 , 000 µg/l, respectively. 1 . 07 . In July 2005 , Spreckels installed three groundwater monitoring wells at the Site (MW-FO-1 through MW-FO-3) . Spreckels sampled the wells eight times - between July 2005 and October 2008 . The maximum TPH concentration was 3 , 700 µg/L during the June 2005 sampling event in well MW- FO-2 , which is west' of the AGT. MW-FO-2 contained 3 , 000 µg/L in the October 2008 sampling event . The maximum TPH concentrations in MW-FO-1 and MW-FO-3 in 2008 were 380 µg/L and 650 .µg/L, respectively. 1 . 08 . A comparison of soil data from the properties with soil screening numbers for residential land use shows that current conditions at the properties do not present a threat to human health. Drinking water is and will be supplied from off-site sources . Based on the evaluation of human health risks via the potential exposure pathways under a residential land use scenario, it is concluded that there is no significant risk posed by site conditions .