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KLElNFELDER EXPECT MORE APPENDIX A GROUNDWATER SAMPLING AND ANALYSES PLAN (SAP) A.1 GROUNDWATER LEVEL SURVEY AND GROUNDWATER SAMPLING METHODOLOGY Sampling will be conducted greater than 24 hours after well development. Water level measurements will be conducted in all monitoring wells prior to purging and sampling the wells using a conductivity based water level indicator. The existing and new wells will be opened and allowed to equilibrate approximately 1 hour prior to collecting water levels. The water level probe and line will be washed with a liquinox wash and distilled water rinse prior to collecting water levels between the monitoring wells. Nitrile gloves will be worn and changed periodically during the water level survey, as necessary. The depth to groundwater will then be measured in each well according to the general protocol described in Appendix D-4.1. Approximately three to five well volumes will be purged and samples will be collected using a new disposable bailer and polypropylene string and as described in Appendix D- 4.2. Because the string and bailers are new/and or pre-cleaned, decontamination of this down-hole sampling equipment is not required. The bailers and string however will not be allowed to touch the ground during sampling. The sampler will change nitrile gloves before sampling each well and more frequently if the gloves become soiled and/or show evidence or potential cross contamination. Based on the history of the site, Kleinfelder does not anticipate that the existing or new wells will not produce three to five well volumes of water. However if the well does dewater and/or less than 3 well volumes are available to purge using a disposable bailer methodology the well will be left to recover from between 1 to 2 hours. Within that time interval the well will be sounded for sufficient sample volume. If greater than 3 feet of water is available in the well casing, a groundwater sample will be collected at that time without further purging. The smallest sample containers will be filled first with preference to nitrate and coliform bottle sets. Assuming there is not sufficient sample volume in 1 to 2 hours, a final attempt will be made to collect a sample at the end of the day without further purging of the well or possibly the following day assuming concurrence with the RWQCB. Purge characterization sheets will be used during purging of each of the monitoring wells to record temperature, electrical conductivity (EC) and pH. Measurements of each of these parameters will be taken at least every casing volume for each well. The sampling technician/field geologist will evaluate the parameters to determine if the purge water has stabilized sufficiently prior to collecting a groundwater sample. If marked variations are noted in pH and/or temperature or more than 10% deviation is noted from EC measurement during purging of the well, additional purging will be conducted until the parameters stabilize. This will be done prior to sample collection. 48093.E01/ST07R052/CJC/Iv Page A-1 ©2007 Kleinfelder, Inc January 26, 2007