COMPLIANCE INFO_1997 - Laserfiche WebLink

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City of Stockton • French Camp Landfill Groundwater Investigation Task 2 Deliverables No deliverables will be prepared for submittal under Task 2. Comprehensive field logs will be developed documenting all aspects of the well drilling activities. Task 3 — Monitoring Well Development The seven groundwater monitoring wells,CDM-6A;CDM-7A,B;CDM-8A;CDM-9A,B;and CDM-10,will be developed approximately one day following installation. A combination of a surge block(to agitate sediment in the filter pack and well screen),and bailing to remove the sediment, will be performed. The process will be repeated until the majority of the suspended silt and sediment are removed from the well. Dedicated bladder pumps for groundwater sampling will be placed in all the new wells. A steel vault box will be placed over the well heads for protection from vehicular traffic. Development water will be stored on site in a small storage tank. Disposition of the development water will depend on the results of the analytical tests run on the well samples. For the purposes of this proposal,it is assumed that the groundwater from the intermediate and deeper aquifer zones will be sufficiently clean to apply to the site for dust control purposes. Task 3 Deliverables No deliverables will be prepared for submittal under Task 3. Field logs will be prepared documenting the well development activities. Task 4 — Ground and Surface Water Sampling and Analysis Samples of groundwater and surface water will be taken from the monitoring network depicted in Figure 3. Four water zones will be characterized at the French Camp Landfill. The landfill leachate will be monitored by well MW-1A. The uppermost aquifer is monitored with existing wells MW-2 through MW-4,and with proposed wells CDM-6A,CDM-7A,CDM-8A,CDM-9A and MW-10A. A deeper groundwater zone is characterized with samples from the Park Well and the two proposed wells,CDM-7B and CDM-9B. The surface water quality in the sloughs will also be monitored as a part of this program. The table on the following page indicates the analysis to be performed for the groundwater and surface water samples as established by the RFP. Groundwater sampling protocol will follow the procedure outlined in EPA Region IX field sampling guidance. This includes purging three well volumes prior to sampling. The purge water will be stored on site in 55 gallon drums. It is estimated that approximately 60 gallons per well will be generated in purge waters. Disposition of the purge water will depend on the results of the analytical tests run on the well samples. For the purposes of this proposal it is assumed that the groundwater from the uppermost and deeper groundwater zones will be clean and disposed of on site. Landfill leachate from monitoring well MW-1A will be managed consistent with past practices. CDM Camp Dresser&McKee 4 W961250OWN