ARCHIVED REPORTS XR0006429 - Laserfiche WebLink

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CLEAOR-� ATW"! ER G R O lJ P, INC 5 2 3 Soil Vapor Extraction Testing 4n December 21, 1995, Clearwater conducted soil vapor extraction tests on vapor wells VW-1, VW-2, and VW-3 These tests were completed by attaching a vacuum blower (regenerative type Rotron model E7O7) to the wellhead and increasing the vacuum and air flow in steps Air flow from each test well was regulated using a dilution valve at the inlet of the blower Each step lasted approximately 30 to 45 minutes and total testing time on an individual well averaged approximately 2 5 hours During tests, vacuums, air flowrates, hydrocarbon concentrations, and percent lower explosive limit and oxygen were monitored at the test well During tests on vapor wells VW-2 and VW-3, induced vacuums at all monitoring wells (except MW-3) and vapor wells were monitored for radius of influence data Induced vacuums at observation wells were not measured during the test on vapor well VW-1 An air sample was collected from each vapor well at the end of each test for TPHg and BTEX analysis to evaluate the potential hydrocarbon removal rates of contaminants trapped in the vadose zone 5 2 4 Air Testing Following the dual-phase test, an air sparge test was conducted on SW-1 Prior to initiating the test, static water levels and dissolved oxygen content in observation wells were measured The sparge test was conducted using a compressor to pressurize well SW-1 until air flow was induced through the well screen (screened from 23 to 25 feet below grade) Soil vapor was extracted concurrently from vapor well VW-3 in a manner similar to that described above During the air spargxng test, pressure and air flow into the sparge well were monitored, and vacuums/pressures at observation wells were monitored The test was completed in steps using different pressures and flowrates At the end of the test, water levels and dissolved oxygen content were measured for comparison to static levels prior to the test An air sample was collected from vapor well VW-3 at the end of the test for comparison with the air sample analytical results from the simple vapor extraction test accomplished earlier All air samples were analyzed for concentrations of TPHg and BTEX by Trace Analysis Laboratory, Inc 5.3 Feasibility Test Results 5 3 1 Aduifer Test Results The constant discharge test was run for approximately 14 25 hours on RW-1 at a flow rate of 5 gpm By the end of the test, drawdown in RW-1 had stabilized at approximately 6 2 feet from static Drawdown was observed in all wells monitored during the test, including MW-3, located approximately 100 feet downgradient of the pumping well Drawdown observed in neighboring monitoring wells ranged from I D-107,PAR/RAP 9 February 21, 1996