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OCTOBER 17,2005 NOA PROJECT NUMBER E05131A is anticipated that the reference elevation for the professional survey will be NGVD 29 and the horizontal coordinates will be based on the California Coordinate System 83. 2.7 Report of Well Installation A Monitoring Wlell Installation Report will be compiled based largely upon the on-site geologist's boring logs, and the surveyor's report. The report will also include an initial evaluation of the direction and magnitude of the hydraulic gradient based upon well gauging data. No deviations from this work plan are anticipated. However, should field conditions warrant modification of well construction plans identified in this document,then the deviations shall be documented in the well installation report. The on-site geologist will ensure that all drilling and well construction activities are consistent with common practice in the environmental industry and the San Joaquin Environmental Health Department guidelines for well construction. 3.0 GROUNDWATER SAMPLING AND ANALYSIS PLAN Representative groundwater samples are to be collected on a quarterly schedule from the monitoring wells. Those samples will be analyzed at a California certified analytical laboratory for the constituents and physical parameters listed in Table 1 using the USEPA analytical procedures indicated in Table 1. To help ensure that samples are representative of the groundwater environment, samplers will be experienced and will observe good sampling procedures. Good sampling procedures will include donning clean latex gloves at each well and as often as necessary to prevent inadvertently contributing contaminants to the sample, initiating gauging and sampling activities at the up-gradient well and proceeding to the most suspect contaminated well,using new disposable sampling equipment at each well,and cleaning all re-usable equipment prior to use at each well with a non-phosphate detergent(e.g., Liqui-Nox,Alco-Nox) and distilled water. Prior to sampling, all wells will be gauged for depth to water and total well depth using an electronic water-level sounder calibrated to 0.01 foot. If well screen are submerged,wells will be vented to the atmosphere for a minimum of 10 minutes prior to gauging. Depth to water and total well depth readings will be measured relative to the surveyed reference mark at the top of each well casing. Each well will then be purged of a minimum of three wetted casing volumes or until dryness using a new disposable bailer and polypropylene twine. Field measurement of pH and total dissolved solids (or specific conductance) will be conducted at the beginning and the end of purging. Purge water will be collected in a five gallon bucket for the purpose of measuring the volume purged, and the bucket will be emptied to the ground surface at least 40 feet from the well as often as required in a fashion which will not allow for runoff into surface water. Alternatively, a peristaltic pump using dedicated polypropylene tubing at each well may be used for purging and sampling. After purging,groundwater samples will be collected from the sampling device (bailer or peristaltic pump) directly into appropriate 5