Laserfiche WebLink
Stantec <br /> SECOND QUARTER 2009 OPERATIONS MAINTENANCE AND MONITORING REPORT <br /> SHOP 10 MAINTENANCE STATION <br /> ,. Remediation System Operation and Maintenance <br /> July 31, 2009 <br /> Samples of individual wells VEW1 and VEW-2 indicate declines as`well. Since January 2009, vapor <br /> samples have been collected on alternate months from either VEW 1 or VEW-2. Sample results of 8.72 <br /> ppmv in well VEW-1 were reported on April 23, 2009, and 4.73 ppmv on June 25, 2009, continue to <br /> indicate reduced concentrations. Sample results from well VEW-2 showed 161 ppmv on May 18, 2009, <br /> ,k <br /> also indicating a declining trend from previous sampling events. <br /> t - <br /> 4.2 AIR SPARGE SYSTEM OPERATION ; <br /> a - <br /> The AS system was started on June 7, 2006, initially injecting into sparge wells ASW-2 and ASW-3. Air <br /> sparging into sparge wells ASW-1 and ASW-4 began on June 21, 2006. Sparge well ASW-4 has <br /> 1 exhibited variable flow due to the increased depth of the well (96 ft-bgs). The total depth of sparge well <br /> ASW-4 is approximately 20 feet lower than sparge wells ASW-1,ASW-2, and ASW-3. Air sparging into <br /> {' shallow wells during the period occurred at average rates of 4 to 5 scfm per well at pressures ranging <br /> from 10 to 21 pounds per square inch gauge (psig). The compressor was shut down on March 12, 2009, <br /> in need of bearing replacement. The compressor bearings were repaired on May 8, 2009, and the <br /> compressor operated until shutdown on June 25, 2009, <br /> l <br /> is Ws1329401%secor4project-05lcaltranslstockton-shop 1 Mom&m and gw reporiing12M912nd qtr 20091gP_09 omm_N.Goe 4_2 - <br /> P <br /> 1 <br />