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i Quik Stop Market No 121 ! CCI Project No 12118-2 Page 2 (Precision) of Richmond, California to install a pre-pack 314-inch diameter well using their Vzbra Push MD series drilling rig The well was installed by first hand auguring a 6-inch diameter hole to 5 feet Upon completion of the hand auguring, the MD drill rig was positioned over the augered hole and 2 5-inch outside diameter (O D) Enviro-Core casing was then direct pushed to refusal at a depth of 23 feet During pushing of the casing, groundwater was noted at approximately 18 feet below the ground surface A CCI geologist logged the hole by collecting relatively undisturbed soil samples in 2-inch O D by 4 foot long buterate tubing The buterate core tubes were used for logging purposes only No soil samples were collected for laboratory analysis Upon reaching the final well depth, Precision then pulled the 2 5-inch casing out of the hole, attached a disposable tip and pushed the casing back to 23 feet Precision then dropped 314" x 1 5" pre-packed casing through the Enviro-Core casing The Pre-pack casing consisted of 10 feet of 0 020 inch slots with 2112 lone star sand to the top of the pre-pack casing Precision then filled the annular space between the outside of the 1 5 inch casing and temporary 2 5-inch Enviro-Core casing to approximately 2 feet above the top of the slots Approximately 1 foot of bentonite pellets were added as the 2 5-inch casing was removed The well was then sealed with . Portland cement to the surface A 7-inch diameter water tight well cover was then installed over the top of the well A copy of the boring log and well schematic are attached in Appendix B Surveying A licensed land surveyor was retained to survey the monitoring well accurately and to determine the elevation of the well casing The survey ensures accuracy so that the plot plans will portray the data in a manner useful for determining groundwater flow direction The survey included both location and elevation determinations Elevation readings were measured to the nearest 0 01 foot and corrected to mean sea level A copy of the survey measurements is attached in Appendix C Well Development On April 16, 2001, monitoring well MW-8 was developed with %-inch diameter bailer to (a) remove residual silts and clays left from the drilling, and (b) improve the hydraulic conductivity between the well and the natural formation After development,the well was allowed to stabilize for two days, enabling CCI to collect a representative water sample All water collected during well development was placed in a labeled drum and left on the south side of the market i