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USA 65 QTR RPT JUL' 94 Ground water elevations have decreased approximately 2 feet since the last depth-to-water measurements on April 26, 1994 The current ground water elevation gradient across the site indicates a meandering of the potentiometric surface, possibly due to differential drainage to the unconfined aquifer from a change of stratigraphy at this depth of ground water from well to well The ground water gradient from MW4 to MW7 is fairly flat with an average slope of 0 003 feet per linear foot and an overall flow direction to the south southeast, this flow direction is consistent with past interpretations from this site A local ground water ' low' is observed at MW8 This well has reflected ground water ' highs and lows ' from previous gauging periods, MW8 indicates a less conductive well, than the other wells from this site, and ' lags` in gravity drainage in recharge and discharge It is also possible that the area around MW8 is influenced by localized irrigation of the planter area approximately 10 feet west of the well (this may have been the reason for the ground water ' high' from the last gauging period on April 26 , 1994) The potentiometric surface of ground water at MW4 indicates a 'high' during this gauging, this notable high may or may not be as pronounced if MW3 data had been used to determine/interpret flow directions (MW3 Depth to Water data inadvertently was not taken this gauging period) . SITE INVESTIGATION Ground water sampling was conducted on July 28 , 1994 in compliance with the quarterly monitoring requirements for this site The various ground water parameters were determined by 1) recording depth to water (by use of a resistivity meter) at each monitor well , 2) purging and containment of ground water from the wells, 3 ) collecting water samples from the wells , 4) submitting these water samples to a State Certified Analytical testing laboratory via established "chain of custody" procedures The water samples were analyzed for Total Fuel Hydrocarbons (TFH) as gasoline and Volatile Aromatic Hydrocarbons (BTEX) using EPA Methods 5030 and 602 , respectively Laboratory detection limits are as follows TFH is 0 02 mg/L and BTEX is 0 5 pg/L, except where samples were diluted Methods and Procedures The ground water was sampled in four monitoring wells (MW3 , MW4, MW6 and MW8) by a Western Geo-Engineers (WEGE) geotechnician working directly under the supervision of California Registered Geologist #3037 Prior to sampling each well , the WEGE geotechnician measured the depth to ground water using a resistance probe A ground water contour surface was later 3