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I lip 2.0 GROUNDWATER MONITORING, SAMPLING AND ANALYSIS I On December 20, 2000, Ramage Environmental monitored and sampled groundwater from the three on-site monitoring wells, and sampled the on-site domestic water supply well 21 Groundwater Monitoring Upon arrival at the site, each of the wellheads was inspected, unlocked and opened Depth-to- groundwater was measured in each of the wells using a water level indicator capable of measuring groundwater to within 0 01 foot The static depth to the groundwater table, as measured in the three groundwater monitoring wells, ranged from 75 62 feet bgs in MW-2 to 76 59 feet bgs in MW-3 The corresponding groundwater surface elevation ranged from a high of 24 85 feet (arbitrary datum) at MW-2 to a low of 23 73 feet (arbitrary datum) at MW-1 The resulting groundwater surface appears as a regular plane dipping to the north-northeast at a gradient of approximately 0 02 foot/foot Since the groundwater surface was last measured in September 2000, groundwater levels rose an average of 1 72 feet, the gradient increased, and the groundwater flow direction shifted slightly to the northeast A groundwater surface contour map is included as Figure 4 The well construction details, wellhead elevations and groundwater monitoring data are summarized in Table 3 22 Groundwater Sampling and Analysis Following the groundwater level measurements, each of the wells was purged and sampled The wells were purged using a pump and dedicated disposable tubing, until at least three well casing volumes were extracted and/or after groundwater temperature, pH and electrical conductivity values had stabilized Following well purging and recharge, groundwater was sampled from the wells using dedicated disposable bailers and laboratory-supplied containers Each sample container was labeled, packaged in an iced cooler and transported with chain-of-custody documentation to Kiff Analytical, LLC (Kiff), a state of California certified hazardous waste testing laboratory (Certification #2236) Kiff analyzed each of the groundwater samples for TPH-as- gasoline, BTEX, MTBE, DIPE, ETBE, TAME, TBA and 1,2-DCA by EPA Method 8260B 8