ARCHIVED REPORTS_XR0008356 - Laserfiche WebLink

Home Browse Search

I ' 07 May 1999 AGE-NC Project No 95-0104 ' Page 3 of 8 3 1 SOIL VAPOR EXTRACTION/IN-SITU AIR SPARGE SYSTEM PROCEDURES ' Between 18 March 1999 and 15 April 1999, aone-month SVE/IAS pilot test was conducted at the I site The SVE/IAS pilot test was performed to provide additional SVE and IAS data for feasibility analysis, provide immediate protection to the nearby drinking water well and potentially provide enough effective remediation such that no additional active remediation in the hydrocarbon-impacted ' vadose zone would be necessary Imtiation of the IAS pilot test involved installation of two-inch diameter, schedule 40 PVC piping I above ground from a temporary air compressor to the well-head at MW-6 Compressed air was supplied to well MW-6 at an approximate pressure of 10 pounds per square inch (psi) Approximately 5 to 7 psi was required to overcome the water column in the sparging wells I The SVE Clot test was conducted using a vapor extractions stem ES VACLEEN 1000G P g P Y (VES), > manufactured by Environmental Techniques The VES consisted of a positive-displacement blower, Idriven by an internal combustion(IC) engine The inlet of the VES was connected to the well-head at VW-1 utilizing two-inch diameter, schedule 40 PVC casing and installed aboveground The • vacuum was applied to VW-I to cause hydrocarbons in the soil to volatilize and flow through the vacuum pump to the IC engine As noted in the Revised Corrective Action Plan -January 1997, dated 18 February 1997, the theoretical radius of influence of VW-I is approximately 20 feet, and all of the known impacted soil lies within 15 feet of VW-1, VW-1 is adequately screened and placed to address all known impacted soil I The extracted hydrocarbon vapor was destroyed in the IC engine as part of the normal internal combustion process Emissions from the engine were routed through two catalytic converters to maximize the destruction rate of hydrocarbon vapor A Ma nehelic vacuum gauge was attached to the inlet of the VES The air stream from VW-I was g g g ' monitored for the presence of organic vapor using an organic vapor analyzer(OVA) equipped with a photo-ionization detector(PID Thermo Environmental 580A, 10 0 eV, calibrated to isobutylene) The air flow was monitored using a Dwyer DS-200 flow sensor The flow rate was determined from I the measured differential pressure and the piping diameter using a nomograph (Appendix D) Field measurements were recorded at regular intervals throughout the pilot test and are summarized in Table 4 32 COLLECTION AND ANALYSIS OF SOIL GAS SAMPLES IA total of four extracted soil gas samples were collected during SVE/IAS Clot test operation from • g P P the inlet of the VES unit to measure concentrations of hydrocarbon vapor The samples were Advanced GeoEnvironmental,Inc I