Laserfiche WebLink
STATE OF CA.IFORNIA PETE WILSON. Governor <br /> CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD— <br /> CENTRAL VALLEY REGION <br /> 3443 ROUTIER ROAD, SUITE A � <br /> SACRAMENTO, CA 95827-3098 % <br /> PHONE. (916) 361-5600 <br /> FAX: (916) 361-5686 <br /> ,.fir <br /> 19 March 1992 <br /> �A6� 2 4 1992 <br /> '4.HEALµ <br /> Mr. Abel Haines M!jv. <br /> Environmental Protection Office <br /> Bldg. 231, Tracy Location <br /> Defense Distribution Region West <br /> P. 0. Box 960001 <br /> Stockton, CA 95296-0250 <br /> FINAL WORK PLAN FOR WELL EVALUATION AND ABANDONMENT, DEFENSE DISTRIBUTION REGION <br /> WEST (DDRW) , TRACY, SAN JOAQUIN COUNTY <br /> We have reviewed the Final Work Plan for Well Evaluation and Abandonment <br /> submitted on 18 February 1992 for DDRW, Tracy. Our review of the Draft Work <br /> Plan, by letter dated 16 December 1991, revealed that inadequate information had <br /> been provided on the well abandonment procedures. The Final Work Plan provides <br /> sufficient information on the well abandonment procedures to approve of the well <br /> abandonment. <br /> Based on the information provided in the Final Work Plan, we assume that Supply <br /> Wells No. 1 and 2 were installed using a cable tool rig with driven casing and <br /> that there is no annular space in these wells which would require sealing. <br /> Therefore, we concur with the plans to perforate Supply Wells No. 1 and 2 under <br /> the following conditions: <br /> 1. Existing perforations are closed off as indicated by the televideo (TV) log; <br /> 2. Void spaces exist between the casing and the formation in unperforated <br /> casing sections as indicated by the cement bond log; and <br /> 3. Adjacent to relatively high permeability zones in unperforated casing <br /> sections as indicated by the neutron and natural gamma logs. <br /> Perforation of the casing opposite all of the relatively high permeability zones <br /> is unnecessary. Mills knife perforations should be kept to a minimum as <br /> excessive use of this tool may affect the integrity of the well . We believe that <br /> with driven casing, filling the entire casing with cement should provide an <br /> adequate well seal . Considering that this well has not been used (pumped) since <br /> the late 1940's and that the lower portions of the Upper Tulare Formation (below <br /> approximately 150 feet in depth) are not contaminated, as indicated by the <br /> existing ground water monitoring data, this method of abandonment should prevent <br /> potential cross-contamination from the Upper Tulare Formation to the Lower Tulare <br /> Formation. <br />