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' Geologteal Teclacks Ina Page 4 Groundwater Monitoring Report ■ Project No 724 2 February 13, 2006 ■ 1.2 Groundwater Sampling Procedure ■ On November 23, 2005, Del -Tech Geotechnical Support personnel arrived on-site, opened the wells and measared the depth to water with an elec,tiically tau'tted sounding tape The water level reading was recorded to an accuracy of 0 01 foot Iii wells where free-floating ■ product is suspected, a clear disposable bailer is used to gauge the interface No free-floating product was observed during this monitoring event ■ Stagnant water in the well casing was purged using a dedicated Wattera pump as recorded in the field logs -(Appendix C) The rate of well purging was monitored The wells were purged of at least three casing volumes until the groundwater parameters (temperature, conductivity, ■ and pH) had stabilized (Appendix C) Groundwater parameter stabilization was characterized by three successive readings within 10% variance Wells MW -6, MW -7, MW - 11 & MW -110 went dry before three well volumes were purged ' Before a sample was collected, the water level was allowed to recharge to at least 80% of the initial level All purge water removed from the monitoring well was placed in a properly ■ labeled 55 -gallon DOT (Department of Transportation 17-H) approved container and is temporarily stored on-site A dedicated Wattera pump was used to collect each sample Water samples were transferred in a manner that minimizes sample aeration during transfer of the sample into 40-m1 VOA vials preserved with hydrochloric acid All samples were checked for headspace bubbles, labeled, inserted into foam holders and placed into an ice chest cooled to 4°C for transport to the laboratory The sampling technician, while collecting all samples, wore disposable gloves ■ A chain of custody document, listing all samples collected and their intended analyses, accompanied the samples from field to the laboratory, thereby providing a means to track ■ their movement and ensure their integrity 1.3 Laboratory Analyses ' The groundwater samples collected on November 23, 2005, were delivered to Sequoia Analytical Labs of Sacramento, California (certification #1624) for analyses of ' • Benzene Toluene Ethyl Benzene and Xylene (BTEX) by EPA method 8021 (B) ■ • Total Petroleum Hydrocarbons as Gasoline (TPH-G) by EPA method 8015(M) • MTBE by EPA 8021E