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1.0 Introduction On May 15, 1997 groundwater monitoring and sampling was performed at the San Joaquin Catholic Cemetery The site is located approximately one mile north of downtown Stockton, California(Figure 1) 2.0 Groundwater Gradient ' Depth-to-groundwater measurements were taken in all five groundwater monitoring wells and two of the four vapor extraction wells (VW-1 and VW-2) to evaluate groundwater flow and gradient characteristics (Figure 2 - Site Plan) The depth-to-groundwater at the site ranged from 43 01 to 44 19 feet below ground surface The elevation of the groundwater surface beneath the ' site ranged from a low of 26 10 feet below mean sea level (msl) in MW-5 to a high of 25 99 feet below msl to MW-3 Groundwater levels have risen an average of approximately 7 feet since the last monitoring event on February 14, 1997 The groundwater surface is above the well screen interval in MW-1, -2, -3, -4, and-5 Groundwater monitoring data are summarized in Table 1 The groundwater flow direction and gradzent are illustrated on the groundwater surface map � (Figure 3) In general, the maximum groundwater gradient was calculated at approximately 0 004 ft/ft in a northerly direction Groundwater flow and gradient characteristics may be unreliable because groundwater levels are higher than the top of the monitoring well screen ' intervals 3.0 Groundwater Sampling and Analyses In the past, the five on-site monitoring wells have been sampled during quarterly groundwater ' monitoring Due to the rise in the groundwater surface elevation of approximately 20 feet since May of 1992, the screen intervals of these wells are below the groundwater surface and may not ' provide an accurate representation of groundwater table conditions In order to collect groundwater samples representative of groundwater table conditions, two vapor extraction wells ' (VW-1 and VW-2) were sampled this quarter These wells were installed near the former tank excavation and have screen intervals coinciding with the water table In addition, an irrigation ' well, irrigation well 42, was sampled at the request of San Joaquin County Environmental Health Division (SJCEHD) Vapor extraction wells VW-1 and VW-2 were purged of at least three well volumes using a 1