ARCHIVED REPORTS_XR0010434 - Laserfiche WebLink

Home Browse Search

1 INC Ile 2.0 SITE BACKGROUND The area surrounding the Site has been charactorized by a mix of airport and agricultural ' usage for over 40 years The Site has been in existence since the early 1950s as an airplane fueling station and was expanded to its present size of approximately 25 acres in 1974 The fuel storage for the Site was originally located in three 5,000-gallon steel USTs installed in the early 1950s These USTs were removed in 1990 The USTs were oriented east-west and rested on a six-inch thick concrete slab The slab remains in place at an estimated depth of 11 feet bgs The ' fuel dispensers were originally located on the north side of the USTs During the 1974 expansion/modernization, the dispensers were relocated 30 feet to the east Aviation gasoline was reportedly stored in the USTs until the early 1960s, when turbine powered aircraft began ' replacing older piston powered planes From approximately 1962 until 1989, JP-4 was stored in the USTs Fuel loss from the USTs was not identified during inventory monitoring Inventory monitoring was accomplished by weekly sticking There is no record of a precision leak test having been performed on the three USTs There is no record of any repairs of the USTs, however, as described previously, the dispensers were relocated 30 feet to the east during the 1974 expansion 21 Underground Storage Tank Removal The three 5,000-gallon USTs formerly on site as shown 1n Figure 2 were taken out of operation in 1989 and removed in January 1990 The former USTs reportedly appeared intact and not leaking at the time of removal Five soil samples (1 through 5) were collected from the soil beneath the tanks at the time of removal by Blaine Tech Services, Inc Samples 1 through 4 were collected along the edge of the concrete slab and sample 5 was collected beneath the slab after a hole was cored through the slab Analytical results from sample 1 indicated 1,500 ' milligrams per kilogram (mg/kg) total petroleum hydrocarbons as diesel (TPH-D) and 1,600 mg/kg TPH as jet fuel, sample 4 contained 3,500 mg/kg TPH-D and 5,100 mg/kg TPH as jet fuel TPH-D, TPH as jet fuel, and BTEX were not reported at or above laboratory detection limits in any of the other samples Records related to the former UST piping were not available, but due to the close proximity of the dispensers to the former USTs, the amount of piping was most likely minimal As soil adjacent to the USTs was impacted with petroleum hydrocarbons, an Unauthorized Release Form (No 90-U 11) was completed and submitted to the PHS/EHD on January 31, 1990 Proposition 65 notification (No 90-022) was also submitted at this time Sample locations and analytical results as presented by previous consultants for the soil samples collected during the UST removal, and subsequent investigations were detailed in Versar's Site Investigation Workplan, dated August 2, 1995 3