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FALL AEK ENGINEERING, INC. 0 Civil• Environmental• Water Resource Engineering and Sciences April 24, 200 -(831)426-9054 P.O.Box 7894,Sante Cn¢,CA 95061 Fax (831)426-4932 Mr. Timothy R. O'Brien Central Valley Regional Water Quality Control Board 3443 Routier Road o Sacramento, CA 95827-3003 N EASTSIDE WINERY,LODI, SAN JOAQUIN COUNTY MONITORING WELL INSTALLATION REPORT OF RESULTS A. Well Construction Monitoring Well 4 was installed at the site on April 20,2002. The well was drilled 27 feet and the bottom of the completed well is 27 feet below ground surface(bgs). Atlas Engineering Services of Redwood City drilled the wells. The equipment was a six-inch hand auger with 30 feet of drive pipe. The cuttings log was prepared from the continuous return of cuttings. The highest occurrence of free water was at 12 feet bgs but this proved to be an insubstantial perched pocket. A water table was next encountered at 22 feet bgs. At 27 feet bgs fat sticky clay was encountered and this is assumed to be the lower limit of the first water bearing zone. From 4 feet bgs downward the color of material encountered was always gray to black and thus is assumed to be in a reduced state The casing string was assembled at the ground surface from 2-inch Schedule 40 PVC threaded well casing. The string consisted of 10 feet of 0.020-inch slotted screen with a threaded cap on the bottom and 20 feet of blank threaded casing. There were 3 feet of stick up when the casing was in place. Number 3 sand was dropped in from the surface after the casing string was in place. The sand pack extended above the water table and above the screened section to 14 feet bgs. When the sand was in place the well was repeatedly bailed empty using a plastic bailer. An effort was made to surge water through the sand pack by rapidly raising and lowering the full bailer. This was carried on for slightly more than an hour. Bentonite pellets were placed in the annulus on April 20 and hydrated. A grout seal (cement with about 3 percent added bentonite powder) was placed on April 22 in the presence of the inspector from the San Joaquin County, Department of Environmental Health. A stovepipe type lockable protective sleeve was placed over the well. The top of the well casing is sealed with a 2-inch expanding test plug. This device is water tight even if submerged in a flood. A diagram of the well is attached. A site plan showing all other monitoring well locations is also attached. The elevation and location of the well head were measured from the previously surveyed well heads. The pertinent details are entered on the diagram.