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Following well construction, the wells are developed in accordance with agency protocols by intermittently surging and bailing the wells. Development is deemed sufficient once pH, conductivity and temperature stabilize to within the 10 percent of the previous two readings and turbidity is below 10 nephelometric turbidity units (NTUs). Hydropunch® Sampling Each grab groundwater sample will be collected using a modified HydroPunch® sampler. Prior to sampling, a water level meter will be used to confirm that the drive rods do not contain water. The sampler will be driven to approximately 3 feet below the desired sampling depth and retracted 3 feet to expose the disposable schedule 20 polyvinyl chloride (PVC) screen and allow groundwater to enter the HydroPunch® sampler. The water sample will be collected by lowering a %"-diameter stainless steel bailer through the drive rods to groundwater. The groundwater will be bailed from the drive rods, decanted from the bailer into 40-mi VOA vials, and capped. Each VOA vial will be checked to ensure no bubbles are present, labeled, placed on ice, and transported to the laboratory under chain-of-custody documentation. The drive rods will be retracted, leaving the disposable drive ti and 4 foot length of PVC well screen in the hole. p 9 Monitoring Well Sampling The sampling procedure for each well includes measuring the water level and checking for the presence of separate-phase hydrocarbons (SPH), using either an electronic indicator and a clear Teflon@) bailer or an oil-water interface probe. Wells not containing SPH are purged of approximately three casing volumes of water (or to dryness) using a submersible pump, centrifugal pump, gas displacement pump, or bailer. The equipment and purging method used for the current sampling event will be noted on field data sheets. During purging, temperature, pH, and electrical conductivity will be monitored in order to document that these parameters are stable prior to collecting samples. After purging, water levels are allowed to partially recover. Groundwater samples will then be collected following purging using a disposable TeflonO bailer, placed into appropriate EPA-approved containers, labeled, logged onto chain-of-custody documents, and transported on ice to a California state-certified laboratory. Sampling equipment will be thoroughly cleaned prior to and following the collection of each sample. Laboratory Procedures Selected soil samples and HydroPunch groundwater samples will be analyzed for the presence of TPHg, BTEX, fuel oxygenates (MtBE, TAME, DIPS, EtBE, TBA, ethanol), and lead scavengers (1, 2-DCA and EDB) using EPA Method 82608. Soil Cuttings and Rinsate/Purge Water Soil cuttings and rinsatelpurge water generated during the installation of the groundwater monitoring wells, and development of the groundwater monitoring wells will be stored on- site in DOT-approved 55-gallon steel drums pending characterization. A label is affixed to the drums indicating the contents of the drum, suspected contaminants, date of generation and the monitoring well number from which the waste water was generated. The drums will be removed from the site by a licensed waste disposal contractor, to an appropriate