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SAN JOAQUIN LOCAL HEALTH DISTRICT APPLICATION FOR PERMIT (Supplemental Information) The three proposed wells are located as shown on the attached Plate 1 . These locations have been selected primarily on the basis of the technical needs of the groundwater study that is underway. A secondary consideration was the suit- ability of the individual sites in terms of ease of construc- tion, whether they are out of the way, and whether they will interfere with other City operations . All drilling locations , methods , and well designs will be approved by the DHS and RWQCB prior to commencement of our field operations. PROPOSED MONITORING WELL DESIGN The wells to be constructed at each of the proposed sites will be 6 inches in diameter, 250 feet deep (approximately) , will be screened in the bottom 20 feet, have a gravel pack surrounding the screen, and will be grouted from the top of the gravel pack up to the surface. Stainless steel well screen and steel casing will be used to construct the well. The wellhead completion will be flush with the ground sur- face. A christy (water meter) type box, including steel lid, will be set in a 2 feet by 2 feet finished concrete pad. Inside the box, there will be a locking steel cover on the well casing. Small submersible pumps may be permanently installed in each well. The methodology involved in constructing the wells at each site , will be as follows : 1) drill a small diameter mud rotary pilot borehole for geophysical logging down to about 400 feet, abandon by tremie grouting; 2) approximately 10 feet from the pilot borehole, drill a cased air rotary borehole for depth sampling of water in various aquifers down to about 250 feet; 3) remove casing from the air rotary borehole and ream out by mud rotary methods to 14 inches in diameter; 4) install a 6-inch diameter steel monitoring well and complete wellhead; 5) develop the well and perform test pumping and water sampling. PROPOSED MONITORING WELL LOCATIONS The proposed monitoring well locations are shown on Plate 1 . Details regarding each location are as follows: