Laserfiche WebLink
-s-;� ;�.'.._ �s .�; yam: <br /> 1. H. KLEINFELDER&ASSOCIATES <br /> 5 CONCLUSIONS <br /> 1. The vapor extraction system has been <br /> successfully installed and <br /> operated at Guild for 456 hours. It has been affective for removing <br /> total petroleum hydrocarbons from the vadose zone. <br /> .. t <br /> 3 <br /> 2. A conservative estimate of the total mass of petroleum hydrocarbons <br /> removed is approximately 230 lbs for the operating period, which <br /> ' corresponds to an average of 0.48 lbs/hr removed. High hydrocarbon <br /> removal rates have been recorded after weekend shutdowns as <br /> r illustrated on Plate 7. <br /> �r 3. The time-hydrocarbon removal rate profile shows an exponential decay <br /> curve and has presently leveled to about a 0.25 lbs/hr renoval rate. <br /> i It is necessary to carefully monitor extraction rates after extended <br /> -r• - <br /> periods of shutdown. <br /> 4, The baseline soil vapor measurements reveal that the hydrocarbon <br /> vapors appear to be concentrated within an area about 40 feet in <br /> diameter and from 15 to 30 feet below the surface. The effective <br /> radius of influence of the vapor extraction system was demonstrated to <br /> be greater than 20 feet. This resulted in a 2-inch water pressure <br /> drop at P-3 with a corresponding vacuum of 4.5 inches mercury at the <br /> vapor extraction well. <br /> 5. The PID appears to be an effective instrument for field monitoring the <br /> TPH concentration in the exhaust gas. It is necessary to correlate <br /> the PID field instrument measurements and actual samples analyzed by a <br /> certified laboratory. <br /> 6. The flow rate and the TPH concentrations achieved equilibration <br /> shortly after the vapor extraction .system is switched on (typically <br /> 2--3 minutes). <br /> 41-87.137 14 1 <br /> v <br />