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' Draft Supplemental Environmental Impact Report Page IV.G-6
<br /> Forward Inc.Landfill 2018 Expansion Project
<br /> and are designed to evaluate surface water quality impacts from the landfill.The designated
<br /> ' sampling points are within the affected area of the proposed expansion.
<br /> Beneficial uses of Littlejohns Creek,per WDR 2014-006, and as specified in the San Joaquin
<br /> River Basin Plan, are agricultural supply, industrial service and process water, contact and non-
<br /> contact water, recreation, municipal and domestic supply,warm and cold fresh water habitat,
<br /> preservation of rare,threatened, and endangered species, and groundwater recharge.
<br /> ' Surface water samples are collected quarterly for field parameters (temperature, specific
<br /> conductance,pH, and turbidity), and, chloride, sulfate,nitrate as nitrogen, total suspended
<br /> 1 solids(TSS),total dissolved solids (TDS),bicarbonate, carbonate,, ehemirzal oxygen demand-,
<br /> dissolved metals(calcium,magnesium,sodium, potassium), volatile organic compounds, and
<br /> total petroleum hydrocarbons(oil and grease). Surface water sampling and analysis are not
<br /> always performed at the Austin Road and Forward Units because, at times, there is no water to
<br /> sample at those points.
<br /> Surface water discharge from the onsite stormwater/sedimentation ponds to the creek is
<br /> monitored quarterly. However, surface water discharges from the onsite ponds to the creek
<br /> only occur during unusually high rainfall season events.With one exception, since 2008,all
<br /> ' surface water has been retained onsite,
<br /> even during the relatively higI4 r-ainfall year-of 201.6-
<br /> 244-7.There have been no reported detectable VOCs in the surface water samples collected in
<br /> the recent samples.A comparison of the upgradient and downgradient surface water samples
<br /> ' showed similar inorganic constituent concentrations, suggesting the landfill units are not
<br /> significantly impacting surface water quality.
<br /> NPDES Stormwater Monitoring Program
<br /> ' The Forward Landfill has a current NPDES monitoring program and SWPPP in place. These
<br /> programs, overseen by the RWQCB, include stormwater inspection, sampling, observation, and
<br /> ' reporting. Previously,treated groundwater was discharged to receiving waters at LittleJohns
<br /> Creek but that has been replaced by use of the treated groundwater(as permitted under R5-
<br /> 200-53-0080) to: 1)use for onsite dust suppression and other operations uses, or 2) use for
<br /> ' artificial recharge reinjection into the local aquifer.As the landfill expands,the facility is
<br /> required to update its NPDES and SWPPP.
<br /> Groundwater
<br /> Regional Groundwater Conditions
<br /> Underlying San Joaquin County is a portion of the vast subsurface groundwater aquifer system
<br /> of the Central Valley of California. Groundwater occurs in unconfined and confined conditions.
<br /> ' Previous Forward Landfill EIRs have presented the regional hydrogeological conditions,which
<br /> have not changed.The upper regional aquifer is typically an unconfined aquifer within the
<br /> Victor Formation geologic unit.A minor perched water table at an elevation of about 20 feet
<br /> amsl was encountered while drilling one of the site wells;perched water tables in the area are of
<br /> ' a limited extent.The Victor Formation consists of over 100 feet of interbedded clay, silt, and fine
<br /> to coarse sand and gravel. Sedimentary formations underlying the Victor Formation include
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