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2.0 GROUNDWATER MONITORING, SAMPLING AND ANALYSIS ' On March 26, 2003, to comply with quarterly groundwater monitoring requirements and to evaluate the stability of the plume of impacted groundwater, Ramage Environmental monitored ' and sampled 10 of the 11 monitoring wells, and collected a groundwater sample from the nearby cemetery irrigation well #2 Monitoring well MW-1 was not monitored or sampled due to damage at the wellhead ' 21 Groundwater Monitoring ' Depth-to-groundwater measurements were taken in all ten of the accessible groundwater monitoring wells to evaluate groundwater flow and gradient characteristics In the ten wells monitored, the depth-to-groundwater beneath the site ranged from 42 33 feet below ground surface (bgs) at MW-4 to 46 02 feet bgs at MW-7 MW-7 is the only well completed above-grade and protected with a monument casing The groundwater elevation beneath the site ranged from a high of 25 51 feet below mean sea level (MSL) at MW-2 to a low of 25 96 feet below MSL at MW-81B The cumulative groundwater monitoring data are summarized in Table 1 Separate groundwater surface maps are included for the shallow-constructed wells (Figure 4) and the deep-constructed wells (Figure 5) Using the shallow-constructed wells, the groundwater gradient is approximately 0 0014 foot/foot in a north-northeast direction Using the deep-constructed wells, the groundwater gradient is approximately 0 0020 foot/foot in a north- northeast direction These groundwater surface configurations are generally consistent with historical groundwater gradients and flow directions 22 Groundwater Sampling and Analysis Groundwater was sampled from six monitoring wells (MW-2, MW-3, MW-4, MW-5, MW-6 and MW-7), the two-well monitoring well cluster (MW-8A and MW-8B), two deep soil vapor extraction wells (VW-1 and VW-2), and Irrigation Well #2 Each of the monitoring wells and deep soil ' vapor extraction wells was purged of at least three well volumes using a pump and disposable tubing Following purging and recharge, groundwater samples were collected from the wells using dedicated and disposable sampling bailers Irrigation Well#2 was allowed to flow at the ' wellhead until the downhole pump was automatically activated A groundwater sample was collected directly at the wellhead through a sample port 5 •