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SJCEHD indicated that once the above items have been completed, the site would be discussed with the CRWQCB to determine If further action is required At the request of the State of California Department of General Services, Klemfelder prepared a proposal and cost estimate dated July 26, 2004, to address the requests of the SJCEHD Additionally, the State of California Department of General Services requested the preparation of a Request for Closure Report FIELD ACTIVITIES Klelnfelder collected groundwater samples from the four monitoring wells (MW-1 through MW- 4) on October 14, 2004 and the top of well casings were surveyed on October 27, 2004 The sampling was coordinated with SJCEHD A representative of the SJCEHD was present during sampling and approved of Kleinfelder's sampling protocols Additionally, Klemfelder conducted a Sensitive Receptor Survey on October 25, 2004 The results of the Sensitive Receptor Survey are presented in Appendix A ' Groundwater Levels On October 14, 2004, Klemfelder measured the depth-to-groundwater in four monitoring wells using a using conductivity-based water level indicator The water level indicator was cleaned with a soap wash, followed by a distilled water rinse, prior to use in each well to reduce the potential for cross-contamination Measurements were made on the north rim of the monitoring well PVC casing Measurements were made to the nearest 0 01 foot Monitoring well locations are shown on Plate 2 Monitoring well construction details and depth-to-groundwater measurements are presented in Tables 1 and 2 The water level measurements were converted to elevations using the surveyed casing elevations Groundwater elevations for October 2004 ranged from 23 77 (MW-2) to 23 57 (MW-1) feet MSL and were generally 0 5 feet higher than the elevations from the previous sampling event in April 2004 The gradient direction was northeast, with a relatively flat gradient of approximately 0 005 A groundwater elevation contour map for the October 14, 2004 is shown on Plate 3 The groundwater elevation for MW-4 was not included in the contouring due to the well being ' screened in a deeper groundwater zone than the other wells The October 14, 2004 gradient and direction were similar to past sampling events ' Monitoring Well Sampling On October 14, 2004, Kleinfelder collected samples from the four groundwater monitoring wells Kleinfelder's sampling protocol for each monitoring well was as follows • The volume of water in gallons standing in the well was calculated by subtracting the depth- to-groundwater measurement from the known depth to the well bottom and multiplying by the cross-sectional inside area of the well casing A transparent single-use disposable bailer was lowered approximately halfway into the surface of the water standing in the well and then withdrawn to check for a petroleum layer or sheen on the water A minimum of three well volumes of water was then purged from each well using a single- use disposable bailer A new disposable bailer was used to purge each well, and a new disposable bailer was used to sample each well Purge water was stored on site in a sealed • and labeled 55-gallon drum Samples were collected after purging by decanting samples from the disposable bailer directly into bottles provided by the analytical laboratory l( 49014-11SAC4R482 Page 2 of 6 November 18,2004 ' Copynght 2004 Klemfelder,Inc KLEINFELDER 3077 Fite Circle, Sacramento,CA 95827-1815 (916) 366-1701 (91 6)366-7013 fax