WORK PLANS - Laserfiche WebLink

Home Browse Search

APR 20 194 03:50PM OGDEN PROJECTS ENVIRONMENTAL DPT P.5i10 WORK PLAN FOR GROUNDWATER MONITORING AT THE SrM OF THE FORMERTOM'ONSRS TREATMENT FACMXff DRIVE1900 NAVY STOCK TON, CALIFORNIA APRIL 1994 INTRODUCTION The Stockton Soils Treatment Facility(SSTF), which was constructed, owned and operated by Ogden Environmental Services, Inc., a subsidiary of Ogden Projects,Inc. (Ogden),ceased operations in 1992. All equipment and structures have been removed from the site. During its four years of operation, the SSTF accepted non-hazardous hydrocarbon-contaminated soils, primarily from the adjacent Tillie Lewis Foods cannery site, and thermally treated it to permanently destroy the organic contaminants and render the soil inert. At the request of the Central Valley Region of the California Regional Water Quality Control Board (CRWQCB) that Ogden further characterize the groundwater beneath the site of the SSTF, Ogden has proposed that a new fourth groundwater monitoring well be installed as a background well. By agreement with the CRWQCB, it will be located southwest of the former contaminated soil stockpile area as shown in Figure 1. The field protocols of this well installation and the monitoring of this and three other groundwater monitoring wells are described in this Work Plan. Applicable permit(s) for installation of a fourth well will be obtained from the San Joaquin County Public Health Services- GROUNDWATER WELL. INSTALLATION Monitoring Well Construction One soil baring will be advanced south-southwest of the soil stockpile area to a depth of approximately 30 feet below surface grade (bsg) or approximately 10 feet into groundwater. Following completion of the boring, the groundwater monitoring well will be constructed as follows- 1. The monitoring well will have easings consisting of 2-inch inside diameter, flush- threaded joint, Schedule 40 PVC pipe. The well will be constructed in a 8-inch diameter boring. 2. Well screen sections will be perforated with 0.010-0.020-inch factory-cut slots. The perforation sieve openings will be assessed (and modified if required) after the borings are logged, and if warranted,a sieve test has been performed and the results received. The screened section of the well will be covered with a 1