ARCHIVED REPORTS_XR0008587 - Laserfiche WebLink

Home Browse Search

4r) Former Beacon Station No 12419 f F October 26, 2005 Stockton, California _ Groundwater Monitoring Report Groundwater Monitoring Results Depth-to-groundwater measurements were subtracted from the surveyed TOC elevations to calculate groundwater elevations Groundwater elevation data were used to construct the groundwater elevation contour map shown on Figure 2 The data indicate groundwater in the underground storage tank area flowed roughly northwestward under a gradient of approximately 0 003 Groundwater analytical results are summarized in Table 1 Benzene concentration data from this sampling event were used to construct the benzene isoconcentration map shown on Figure 3 The analytical report is contained in Attachment C Vapor Extraction System Monitoring Installation of a vapor extraction system (VES) and an air sparge (AS) was completed in late July 2005 The San Joaquin Valley Air Pollution Control District (APCD) issued Authority to Construct permit No N-4910-1-1 on July 14, 2005 Operation of the VES was initiated on August 2, 2005 Inspection of the VES is scheduled for October 11, 2005 The location of the remediation system compound and underground piping is shown on Figure 4 The VES consists of a positive-displacement blower rated at 100 cubic feet per minute (cf n), an EVAX 520 catalytic oxidizer and other associated equipment as shown in the process flow diagram on Figure 5 The VES is set up to extract vapors from vapor extraction wells VW-1 and VW-2, and monitoring wells MW-7, MW-9, MW-10 and MW-11 Soil vapor flow from each well is controlled by individual valves The AS consists of a 1 5 horsepower, • 7 5 cfm air compressor and other associated equipment as shown on Figure 5 The AS is set up to sparge air to sparge wells AS-1, AS-2, AS-3 and monitoring wells MW-1 and MW-3 Air sparging was not initiated during third quarter 2005 The VES reporting period for this report is August 2 to September 25, 2005 The VES operated -- - - ----- for=a=total=of=approximately 28=days=Influent=and=effluent=vapor-samples=were=collected=on-- _ August 2 and 11, and September 13, 2005 Analytical reports are contained in Attachment C T Vapor extraction system data are summarized in Table 2 The average influent flow during the third quarter was approximately 24 standard cubic feet per minute Approximately 797 pounds of TPHg and 0 6-pound of benzene were removed by the VES through the end of the third quarter reporting period GeoTracker Electronic Data Deliverables The analytical electronic data deliverable (EDD) was prepared and uploaded by Kiff The groundwater level EDD (GEO_WELL) was prepared and uploaded by Horizon The GEO_WELL upload confirmation sheet for this quarter and the Quarterly Monitoring Report EDD (GEO_REPORT) upload confirmation sheet for the previous quarter are contained in Attachment E 01 419gmrQ305 Project No 1419 48 2 HORIZON ENVIRONMENTAL INC. i