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Project Number 1804BK01 September 17.2003 remaining annular space. The wellhead will be equipped with a locking cap and a traffic- rated steel box set in cement slightly above grade to complete the installation. Well Development Approximately forty-eight (48) hours after installation of the monitoring and aquifer test wells, they will be developed to remove fines and settle the filter pack. This will be accomplished using the 'surge blocking and bailing' method and/or pumping using a submersible pump. It is anticipated that at least ten (10) well casing volumes will be removed from each well during development. Groundwater Monitoring and Sampling Groundwater at the newly installed monitoring wells will be monitored and sampled at least 24 hours after development of the wells. Depths to groundwater will be measured from the top of casing (TOC) to the nearest 0.01-foot using a Solinst water level meter. Depths to water will be used to calculate the groundwater elevation at each well for generation of shallow and deep zone groundwater gradient plots. The monitoring wells will be sampled using low-flow purging and sampling techniques. A low-flow bladder pump will be slowly lowered to a depth approximately five feet below the water table to minimize mixing of water stored within the casing. The pump will be operated at a low-flow rate of approximately 0.1 gallon per minute (gpm) to purge the well minimizing drawdown. The water level will be monitored during purging to limit drawdown to 4 inches. Periodically during purging the pH, temperature, and electrical conductivity parameters will be measured. Groundwater will be considered stabilized and representative of the aquifer when three consecutive measurements are within ± 0.1 for pH, ± 3% for electrical conductivity, and ± 10% for temperature. After purging, a groundwater sample will be collected directly from the pump discharge into two 40-milliliter VOA vials. Care will be to verify that headspace or bubbles do not exist and each VOA vial will be sealed using a Teflon®-lined lid. The samples will be labeled and placed in an iced cooler maintained at 4° Centigrade, and accompanied with a chain- of- custody document for transport to the analytical laboratory. All downhole equipment will be cleaned prior to use and between wells by washing using an Alconox solution and rinsing with clean potable water. Soil Gas Sample Analysis The soil gas samples will be transported via overnight carrier to Columbia Analytical Services, Inc. of Simi Valley, California, a State of California Certified Analytical Laboratory, for chemical analysis. The samples will be analyzed for VOCs using EPA Method TO-14A Modified. The permissible holding time for the analysis is seventy-two (72) hours. The detection limit will be 0.005 microgram per liter (,ug/L) for each volatile organic compound. Soil Sample Analysis Selected soil samples will be transported via overnight carrier to Halcyon Laboratories, Inc. (California State-Certified analytical laboratory #1920) in accordance with State guidelines and EPA protocols. The samples will be analyzed for VOCs using EPA Method 5035/8260b within forty-eight (48) hours of collection as specified by the analytical method. The VOC detection limit will be 0.1 milligram per kilogram (mg/Kg). E,C Remediation 5