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Kennedy/Jenks Consuhants and sampling. General procedures for well construction are presented in Kennedy/Jenks' Standard Operating Guideline —Well Construction and Development(Appendix D). The locations and well casing elevations of these new monitoring wells will be horizontally and vertically surveyed by a licensed land surveyor. The ground surface and top of well casing elevation will be surveyed to the nearest 0.01 foot relative to mean sea level using the National Geodetic Vertical Datum (NGVD 1988), relative to nearest benchmark at the Site. Horizontal locations of the new wells will also be surveyed to the nearest 0.1 foot relative to the California Coordinate system. 5.2.3 Evaluation of Zones of Higher Hydraulic Conductivity During advancement of the borings, special attention will be given to the moisture conditions, especially in zones of potential higher hydraulic conductivity. In the event that a sample has more moisture than "damp" or"moist", but not necessarily saturated, drilling will stop for a minimum of two hours. Typically the augers will be pulled up approximately five feet to allow the zone to flow water freely into the borehole, but this may not be appropriate if cave-in potential is high. Seals will not be used on the hollow stem augers, so even without pulling the augers up, water will still be able to flow into the borehole. After the appropriate amount of time, a conductivity based water level tape will be lowered into the borehole to detect the presence of water. If water is found in the borehole, drilling will proceed to determine the thickness of the water bearing zone and a monitoring well will be installed as described above. If water is not present, drilling will proceed to the target depth, stopping again if moisture conditions indicate the potential presence of water. 5.3 Groundwater Sampling Initial sampling of groundwater will be conducted from the newly-installed monitoring wells no sooner than 72 hours after these wells have been developed, in accordance with Kennedy/Jenks' Standard Operating Guideline —Groundwater Sampling (Appendix E). Groundwater will be purged from the monitoring wells prior to sampling to acquire samples representative of aquifer conditions. The field parameters pH, temperature, and electrical conductivity will be monitored during purging to document stabilization of groundwater quality in accordance with Kennedy/Jenks' Standard Operating Guideline —Field Measurement of pH, Temperature, and Conductivity (Appendix F). Field parameters will be recorded on a groundwater purge and sample form. Groundwater samples will be collected into appropriate containers provided by the analytical laboratory using a new disposable bailer or a positive displacement pump. One duplicate sample will be collected during each sampling event. Following collection, the samples will be labeled and placed into a chilled container held at four degrees Celsius. The samples will be submitted in the chilled container to a state-certified analytical laboratory using chain-of-custody procedures to document the sample handling process. The groundwater samples will be analyzed for the following water quality constituents and parameters by the analytical laboratory following their normal turnaround time and internal quality assurance/quality control (QA/QC) procedures: e Boron by EPA Method 200.7 Page 14 Work Plan for Improved Detection Monitoring Program Musco Family Olive Company, Tracy, California a�.a,mpWmnWWX20104 Wm=w1Ne05 ewawt�_27_dmp*f dam n4eport text-09-26.doc