COMPLIANCE INFO_1989-1996 - Laserfiche WebLink

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Aft WASTE DISCHARGE REQUIREMENTS FOR -3- CITY OF STOCKTON AUSTIN ROAD LANDFILL CLASS III LANDFILL SAN JOAQUIN COUNTY 17. Current plans include closure of the existing waste management unit (LF-1), or expansion of the facility in 1995. Expansion would be accomplished by the addition of a new Class III landfill unit (LF-2) in the 45-acre area south of the North Fork of South Little Johns Creek, which is hydrogeologically similar to the area of the existing landfill . 18. The Discharger has implemented a periodic load checking program which consists of daily random checks of incoming loads. Upon selection of a random load for inspection, information such as date, time, source of waste, etc. , will be recorded. Also, signs, prenotification programs, and procedures for handling identified hazardous wastes have been developed. 19. Inspections of the landfill over the past several years have noted that the surface of the landfill was not graded to drain. Rainfall has accumulated in depressions on the landfill surface where it percolated into wastes and became available to generate leachate. Proper grading is needed to prevent rainfall from percolating into wastes. 20. A Solid Waste Assessment Test And Verification Monitoring Plan, dated June 1989, was submitted for the landfill . The report showed that there had been a significant water quality impact at the down gradient ground water monitoring wells MW-1 and MW-4. Volatile organics were found in the down gradient wells, and were confirmed with further sampling. Supplemental sampling results indicated that volatile organics were detected in California Youth Authority (CYA) wells CYA-1 and CYA-2 at levels equal to or slightly above action levels, and in a private well at 8106A Austin Road. However, confirmation sampling results did not detect any volatile organics at either of the CYA wells. Further sampling at the private well at 8106A Austin Road did detect volatile organics, and this well is no longer being utilized for drinking water. 21. Because of the detection of volatile organics down gradient of the landfill , a three phase verification monitoring program was implemented at the site to determine the vertical and horizontal extent of the contamination. Phase I of the plan consists of a camera scan and geophysical log of the on-site water supply well , a continuously sampled soil boring, and a cone penetrometer test (CPT)/hydropunch test. Phase II consists of hydropunch sampling the water in the first two sand zones along the downgradient edge of the landfill and along the upgradient edge of the landfill. The upgradient sampling will be performed to determine if volatile organics are migrating towards the landfill from Forward Landfill . Phase III consists of off-site exploration and determination of the horizontal extent of the problem. The extent of Phase III will depend on the results of Phase II. 22. Phase I of the verification monitoring program has been completed. The results of the CPT/hydropunch test showed that the initial plan to drive several hydropunch holes was not feasible. This was due to a very hard layer of clay that can not be penetrated by the hydropunch. Therefore, the Discharger now plans to auger down through the hard clay layer and then drive the hydropunch through the auger flights into the two water zones to sample. A time schedule