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Draft Supplemental Environmental Impact Report Page IV.G-6
<br /> Forward Inc. Landfill 2018 Expansion Project
<br /> other sampling points,FSW-1 and ASW-2, are located immediately downstream of the landfill,
<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 Littlejohn 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 dissolved solids
<br /> (TDS), carbonate,, chemical oxygen demand, dissolved metals (calcium,magnesium, sodium,
<br /> potassium), volatile organic compounds, and total petroleum hydrocarbons (oil and grease).
<br /> Surface water sampling and analysis are not always performed at the Austin Road and Forward
<br /> Units because, at times,there is no water to 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. Since 2008 time, all surface water has
<br /> been retained onsite, even during the relatively high rainfall year of 2016-2017. There have been
<br /> no reported detectable VOCs in the surface water samples collected in the recent samples. A
<br /> comparison of the upgradient and downgradient surface water samples showed similar
<br /> inorganic constituent concentrations, suggesting the landfill units are not significantly
<br /> 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 Creek but that has been replaced by use of the treated groundwater (as permitted under R5-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 /> 2005-0080)to: 1)use for onsite dust suppression and other operations uses, or 2)use for artificial
<br /> recharge reinjection into the local aquifer. As the landfill expands,the facility is required to
<br /> 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
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