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GROMATRIX to groundwater was measured in the site monitoring wells before purging Prior to sampling each well, the presence of separate-phase petroleum hydrocarbon was assessed with a disposable bailer About 100 gallons of water was purged from each well using a dedicated stinger and vacuum truck Each dedicated stinger is stored on the site in an individual sealed plastic bag ' Suction on the vacuum truck line remains on during purging and while making and breaking the connection with the individual stingers ' After purging an initial 100 gallons from each well, field parameters (electric conductivity, H, ' and temperature) were measured and recorded on field data sheets (Appendix A) A new, clean disposable bailer was used to collect water from each well for field parameters After the first set of field parameters were collected and water levels had recovered, an additional 50 gallons of ' water was purged with the dedicated stinger New clean disposable bailers were used to collect the groundwater samples for laboratory analysis of volatile organic compounds ' Groundwater samples were preserved and transported under chain-of-custody (Appendix B) ' procedures to Precision Enviro-Tech Analytical Laboratory of Stockton, California, a state-certified laboratory, for analyses The groundwater samples from the six site monitoring . wells were analyzed for total petroleum hydrocarbons quantified as gasoline (TPHg) and ' benzene, toluene, ethylbenzene, and xylenes (BTEX) using U S EPA Method 8260B 3.0 MONITORING RESULTS Third quarter 2003 groundwater elevation data, groundwater flow direction and gradient, and analytical results are discussed in the following sections ' 3.1 GROUNDWATER ELEVATION,FLOW DIRECTION,AND GRADIENTS Groundwater levels measured on August 22, 2003 (Table 1), were used to construct potentiometric contours on Figure 3 No floating product was reported in any of the site wells Groundwater levels have declined about 12 feet in the site monitoring wells since second quarter 2003 Based on the groundwater elevation data, the calculated groundwater flow direction for August 2003 is south to southwest at a gradient of 0 007 (Table 2 and Figure 3) Groundwater flow direction and gradient for third quarter 2003 is similar to flow direction and gradient during first and second quarters 2003 • 1\PR0JECW)0M\6437 OOM6437 13 doc 2