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K L E I N FELDER EXPECT MORE 3 WELL DEVELOPMENT AND SURVEYING 3.1 WELL DEVELOPMENT METHODOLOGY During well installation the well sand pack will be surged for approximately 5 minutes, using surge block attached to a drill rod. The surging will be performed to prevent bridging and to settle the sand pack prior to placement of the bentonite seal. A minimum of 48 hours after installation, the monitoring wells will be developed to remove fine silt from the well bore and to effectively increase the hydraulic radius of each monitoring well. Surging along the screened interval of the well will be performed to draw the sediment from the formation into the filter pack and well and to further set the sand pack. Surging will be done with a suction pump equipped with new food- grade, ribbed tubing, surge block and foot valve. The bottom of the tubing will be fitted with the surge block attached to a ball-valve/foot valve. This valve is designed to allow water and sediment into the tubing, but prevents outflow from the tubing. The well screen interval will be surged for approximately 5-minutes followed by purging using a suction pump. Sediment can also be pumped directly from the bottom of the well using this method. This process will be repeated until the discharge runs relatively clear of fines. The discharge will be periodically monitored for pH, temperature, and specific conductance to evaluate and record groundwater parameters during the development task. The monitoring wells will otherwise be generally developed as described in Appendix D-3.2. 3.2 WELL SURVEY The locations of new monitoring wells, and the elevation of the top of the PVC well casings will be surveyed and tied into permanent markers, if readily available. At a minimum the well elevation survey will utilize a GPS coordinate system that meets the requirement/s of the RWQCB's Geotracker database. Survey accuracy will be approximately 0.1 foot for the "x" and "y" coordinates and .01 foot for the "z" coordinate. The measuring point will default to the north side of the PVC unless an obvious high point/irregularity is noted on the casing. These areas will be marked for the surveyors by the field geologist/water sampling technician prior to the well survey. The depth to static groundwater will be measured from the marked/surveyed point in subsequent water level surveys. The depth of water is then subtracted from the elevation of the top of the well casing to provide a groundwater elevation for each monitoring well location. The new wells will be tied into the existing monitoring well network elevations and locations. The well elevation survey will be conducted by a Licensed Land Surveyor or Engineering firm with the appropriate certifications for performing this work. 48093.E01/ST07R052/CJC/Iv Page 7 of 15 ©2007 Kleinfelder, Inc January 26, 2007