Laserfiche WebLink
mixture was being shared by multiple wells, rather that the one well at a <br /> time, as programmed. ASE allowed the system to continue to operate <br /> since the problem only appeared sporadically. During the week of <br /> September 9, 2002, each of the solenoids was replaced and an in-line air <br /> filter was installed to purify the air before it reached the solenoids. The <br /> manufacturer of the C-Sparger suspected that the "sticking" solenoids was <br /> the result of dust in the air. <br /> On October 2, 2002, ASE personnel discovered that the C-Sparger master <br /> relay had failed several days prior. On October 3, 2002, a new master <br /> relay was installed and the system was restarted. Since that time, the <br /> system has operated continuously. <br /> 7 . 0 WEEKLY SYSTEM OPERATION AND MAINTENANCE <br /> Each week, ASE visits the site to check on the performance of the system, <br /> to make necessary repairs, and to measure the DO in the six groundwater <br /> monitoring wells. The DO readings are tabulated in Table One. No <br /> changes to the programming have occurred. <br /> 8 . 0 GROUNDWATER SAMPLING EVENT <br /> The workplan prepared by ASE called for a sampling and analysis of the <br /> groundwater at the site after the first 30 days of remedial activities. On <br /> September 11, 2002, ASE measured the depth to water in the six (6) site <br /> groundwater monitoring wells using an electric water level sounder. The <br /> surface of the groundwater was also checked for the presence of <br /> free-floating hydrocarbons or sheen. No free-floating hydrocarbons or <br /> sheen were observed in any of the site groundwater monitoring wells. <br /> Prior to sampling, each monitoring well was purged of three well casing <br /> volumes of groundwater using dedicated polyethylene bailers. The <br /> parameters pH, temperature, and conductivity were monitored during the <br /> well purging. Groundwater samples were not collected - until these <br /> parameters stabilized. Groundwater samples were collected from each <br /> well using dedicated polyethylene bailers. <br /> The samples were decanted from the bailers into 40-m1 volatile organic <br /> analysis (VOA) vials and pre-preserved with hydrochloric acid. The <br /> samples were capped without headspace, labeled and placed in a cooler <br /> with wet ice for transport to Kiff Analytical, LLC of Davis, California (ELAP <br /> #2236) under appropriate chain-of-custody documentation. <br /> Singh's Unocal System Installation and Operation Report — October 2002 <br /> -4- <br />