ARCHIVED REPORTS_XR0006758 - Laserfiche WebLink

Home Browse Search

Canepa's Car Wash September 23, 1996 Page-6- The pore volume exchange rates for SV-1, SV-8, and SV-9 are based on a flow rate of 109 SCFM and the parameters presented below VP = IFr`h(0 3) where V,=pore volume(assuming30% , sandy silt REF Soil Mechanics Pe ff l 7 porosity,h' _ 1 ro 9 6, P 41, TbI 2 3) r = radius of influence - ROI (ft) h = height of soil column above groundwater (43 ft) Pore volume exchan a rates (a� 109 SCFM a SV-I = 15 hours b SV-8 = 2 5 hours c SV-9 = 5 5 hours i8 0 INTERNAL COMBUSTION UNIT (ICU) - DISCUSSION During the SVE evaluation, the existing ICU was started and operated for approximately 5 hours The extraction and vapor treatment system include a) a 55-gallon, water vapor knockout drum, b) the remote, SVE blower, and c) a small propane powered internal combustion engine Nine SVE well intake/extraction ports are located adjacent to the ICU system The s stem was set u to be o erated on one SVE well at_a time A 2-inch diameter hose is connected from a selected SVE well port to the knockout drum and from the knockout drum to the blower The air stream is then infected directly from the blower into the ICU carburetor by 2-inch PVC conduit The system is designed to burn the hydrocarbon vapors in the internal combustion engine and exhaust the emissions through a catalytic convertor to the atmosphere However, a valve (hole) located in tine PVC conduit, upstream from the carburetor, released extracted vapors, thereby lowering the efficiency of the system During opeiation of the system, organic vapor concentrations were measured after the blower using a PID The organic vapor concentrations ranged from 80 ppm (SV-4) to 750 (SV-7) with an average concentration of 395 ppm (see field notes, Appendix B) ' Based on our review of the s stem performance, the following was noted Y P � 1) The ICU appeared to be incapable of operating efficiently in its intended configuration H vaive (tioie) had been placed in the PVC conduit on the side of the intake,dust before the carburetor, to reduce the vapor concentration going into the ICU (i e , vent ' hydrocarbon vapors) The system would not run properly when the valve was covered, thus lowering the efficiency of the system to unacceptable levels 2) The system was manifolded to operate on one SVE well at a time In order to optimize the SVE system and decrease the time requited to remove the gasoline in the subsurface, the system should be inanifolded to operate oil various configurations of SVE wells based on the ROI of each well and the extracted vapor concentrations CONDOR