Laserfiche WebLink
I <br /> I27 September 2004 <br /> AGE-NC Proj ect No 01-0827 <br /> IPage 2 of 5 <br />' 2 0. PROCEDURES <br /> Field procedures for ground water sampling are described below All field work was performed in <br />' accordance with Central Valley Regional Water Quality Control Board(CVRWQCB)guidelines for <br /> the investigation of underground storage tank (LIST) sites <br />' 21 OZONE SPARGE SYSTEM OPERATION <br />' The ozone-sparging (OS) system has operated continuously since 01 July 2003, the system was <br /> monitored and serviced at regular intervals throughout the quarter The OS system consists of an <br /> ozone generator, which produces ozone-rich air at 10 standard cubic feet per minute (scfm) and a <br />' pressure of 20 pounds per square inch This ozone-rich air is delivered to the IAS wells IAS-1 <br /> through IAS-3 via a subsurface network of 3/9-inch polyethylene tubing <br />' Because the injected ozone will eventually break down to dissolved oxygen(DO), a DO meter was <br /> utilized at each monitoring well during the monitoring events to determine the effectiveness of ozone <br /> . sparging DO and/or oxidation/reduction potential(ORP)in groundwater wells adjacent to the IAS <br />' wells were measured on 10 August 2004 Dissolved oxygen concentrations have generally increased <br /> in ground water wells since remediation-system startup in July 2003, negative ORP values in the <br />' monitoring wells near ozone injection well IAS-1 suggest a reducing environment around the ozone <br /> discharge points (Appendix A) <br />' 2 2 QUARTERLY WELL MONITORING <br />' On 10 August 2004, the depth to ground water was measured in monitoring wells MW-1 through <br /> MW-6 and vapor wells VW-I through VW-8 <br />' 2 2 1 Well Monitoring and Evacuation <br />' A Solinst water level meter was used to measure the depth to ground water in each well After water <br /> levels were gauged,a Wattera inertial tubing pump or dedicated disposable bailer was used to purge <br /> monitoring wells MW-1, MW-3,MW-5, MW-6, and vapor wells VW-1, W-2d, VW-3 and VW-5d <br />' of a minimum of three casing-water volumes (between 3 and 19 gallons) of ground water <br /> Temperature, pH, and conductivity were measured at regular intervals during purging using an <br /> Oakton model water analyzer Purged water from impacted wells was stored on-site in 55-gallon <br />' drums The field data sheets are included in Appendix A <br />' Advanced GeoEnvironmental,Inc <br /> 1 <br />