Laserfiche WebLink
Metadata
Document management portal powered by Laserfiche WebLink 9 © 1998-2015 Laserfiche. All rights reserved.
R604 :UPDATE 19 5 -19-1993 <br /> June, 1992 all these wells are below detection limits, ¢2 2 MPN, <br /> for fecal coliform <br /> VAPOR EXTRACTION <br /> Vapor Recovery Results: <br /> The vapor extraction system was shut down on November 21, 1991 on <br /> completion of operation under Initial Variance #91-19 and 90 day <br /> Variance #91-20 A total of 13 , 116 pounds of gasoline range <br /> hydrocarbons were removed from the soils and ground water beneath <br /> this site by that time . <br /> The vadose zone vapor recovery wells (P1, P3-Swarm and EX) <br /> contributed little to the total recovered hydrocarbons during <br /> this time period: P1 = 1 3 pounds, P3-Swarm = 561 .4 pounds and <br /> EX = 127 pounds . <br /> The system was restarted under the Authority to Construct Permit <br /> (AP 91-106) on March 31, 1992 <br /> On July 21, 22 , and 23 , 1992 , four new vadose zone vapor recovery <br /> wells were installed and manifolded to the recovery system. As <br /> of February 23 , 1993 the new wells along with MW5 have produced <br /> 3851 4 pounds of gasoline range hydrocarbons, for a total <br /> recovery of 16967 4 pounds From March 15, to April 15, 1993 327 <br /> pounds of gasoline range hydrocarbons have been produced and from <br /> April 15 , to May 14, 1993 283 pounds of gasoline range <br /> hydrocarbons have been produced, as compared to the previous <br /> reported 202 pounds of gasoline range hydrocarbons from February <br /> 23 , to March 15 , 1993 , see Table 3 and Charts, Figures 6A through <br /> 6E of vapor recovery <br /> Vacuum Influence. <br /> As was stated earlier, vapor recovery has removed the lighter <br /> fractions of gasoline range petroleum hydrocarbons from the soil <br /> (through ethylbenzene) and has greatly reduced the petroleum <br /> hydrocarbons dissolved in the ground water beneath this site . <br /> Figure 5 represents the vacuum influence generated from the <br /> vapor recovery system as measured before obtaining depth to <br /> ground water measurements on May 14 , 1993 . <br /> System Operation. <br /> Currently a flow rate that fluctuates between 85 cubic feet per <br /> minute and 90 cubic feet per minute is being maintained through <br /> the two blowers that are placed in series, prior to exhausting <br /> through 2 (in series) 110 gallon and one 85 gallon activated <br /> carbon vapor scrub units . These are serviced by Exceltran and <br /> Cameron Yakima for change-out and rejuvenation From April 23 , <br /> to May 14 , 1993 the system has operated 498 hours and recovered <br /> 223 pounds of gasoline range hydrocarbons (10 75 pounds per day) . <br /> y page 3 <br />