ARCHIVED REPORTS_XR0004263 - Laserfiche WebLink

Home Browse Search

Frontier Transportation, Inc. B23502.01 October 16, 1996 page 4 On August 11, 1995, Twining completed a report of UST removal activities (Twining, 1995). Please note that typographical errors were made in preparing the tabulated data originally presented in the August 11, 1995 report. Table 2 incorporates the corrected data denoted by asterisks. Following removal of the diesel USTs, groundwater was encountered in the bottom of the southern UST excavation. Twining collected three groundwater samples from standing water in the excavation. Groundwater sample analytical results are summarized in Table 3. TABLE 3 Diesel UST Excavation' :Groundwater Sample Analytical Results Sample:Number Benzene Toluene EtWbeaoe€ie Xylenes TI'H-D WS-West <05 <05 <05 <05 240 WS-Center <05 <05 <OS <0S 1,200 WS-East <05 <05 <05 <05 700 TPH-D = total petroleum hydrocarbons-diesel range constituent µg/L = micrograms per Liter < = less than The soil sample analytical results indicate there has been a release of selected PPCs in the vicinity of the gasoline USTs. However, these results did not qualify nor quantify the extent of PPC migration in the subsurface soil. In order to demonstrate whether or not this release of PPCs poses a potential threat to human or environmental health, and if so, what is necessary for cleanup, the work scope outlined in the following sections was conducted. 3.0 PURPOSE AND SCOPE The purpose of this site characterization was to assess and delimit the extent of PPC impacted soil and groundwater so that one or more corrective actions may be identified and proposed. The following scope of work was performed to achieve the stated objective: • Hand augered two soil borings to 3 feet BSG and collect soil samples for chemical analysis to characterize the extent of PPC impacted soil in the vicinity of the former dispenser island and former product piping; • Drilled a total of ten soil borings. Six vertical soil borings and one angle soil boring were drilled and sampled to characterize the lateral extent of impacted soil in the vicinity of the former USTs. Three soil borings were drilled to a maximum depth of approximately 26 feet for the installation of groundwater monitoring wells to characterize the extent of impacted groundwater in the vicinity of the former UST; • Chemically analyzed selected soil samples and groundwater samples in the laboratory for key PPCs.