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NOA No. R5-2003-004410 -3 - 29 May 2003
<br /> Dewatering Discharge
<br /> City of Tracy, Stormwater Pipeline Project
<br /> The Order includes a Monitoring and Reporting Program (MRP) that prescribes minimum wastewater
<br /> monitoring requirements to evaluate compliance with the effluent discharge limitations contained in the
<br /> Order. The MRP includes requirements for the sampling and analytical testing for specific petroleum
<br /> hydrocarbon constituents in both influent and effluent sources. Groundwater extraction, treatment and
<br /> monitoring will continue for approximately 90 days (end of August 2003) after the pilot testing is
<br /> completed and the treatment systems begin continuous operation.
<br /> Depth to shallow groundwater along Byron Road ranges from approximately 5 to 10 feet below ground
<br /> surface and generally flows to the north-northeast. Shallow groundwater in the Tracy area is of poor
<br /> quality and prohibited for use as domestic or municipal supply in accordance with the City of Tracy
<br /> Municipal Code (Section 11.1.16), for administrative reasons unrelated to the presence of degraded
<br /> crude oil/bunker C fuel oil. The Tracy Municipal Code Section 11.1.16 prohibits installation of water
<br /> supply wells in the upper 50 feet. Recent sampling (April 2003) and analysis of shallow groundwater
<br /> along the pipeline route by Regional Board staff indicates concentrations of total dissolved solids (TDS)
<br /> of 2,500 mg/L, boron - 3.3 mg/L, nitrate (NO3) - 45 mg/L, chloride - 620 mg/L, sodium— 370 mg/L,
<br /> potassium—4.6 mg/L, sulfate- 700 mg/L, and hardness (as CaCO3) of 1,100 mg/L.
<br /> CEQA CONSIDERATIONS
<br /> The City of Tracy certified a Final Environmental Impact Report (FEIR) for the Storm Drainage Master
<br /> Plan Supplement No. 1 (Westside Channel Outfall System) in April 2001. The FEIR contemplated that
<br /> the project would require dewatering of trenches and the excavation of petroleum hydrocarbon
<br /> contaminated soils along Byron Road. The FEIR identified mitigation measures to address the
<br /> significant impacts associated with these activities. None of the conditions specified under the
<br /> California Public Resources Code section 21166 exists to require or permit the Regional Board to
<br /> prepare a subsequent or supplemental environmental impact report for this project.
<br /> ADDITIONAL REQUIREMENTS
<br /> 1. The project shall be constructed and operated in accordance with the requirements contained in
<br /> the Order and in accordance with the information submitted in the RWD and attachment dated
<br /> 6 May 2003, and supplemental information dated 13 May 2003. In accordance with the Order,
<br /> the MRP will be implemented at the time the treatment systems are operational.
<br /> 2. For this project, the requirement for sampling and analysis of influent and effluent wastewater for
<br /> lead (total and organic), methyl tertiary butyl ether(MTBE), methanol, ethanol, tertiary butyl
<br /> alcohol (TBA), di-isopropyl ether(DIPE), ethyl tertiary butyl ether (ETBE), tertiary amyl methyl
<br /> ether(TAME), 1, 2-dichloroethane (1, 2,-DCA), and 1, 2-dibromoethane (EDB) is waived unless
<br /> otherwise directed by the Executive Officer.
<br /> 3. For Treatment Systems No. 1 and 4, total petroleum hydrocarbon as diesel (TPH-d), benzene,
<br /> toluene, ethylbenzene, and xylene (BTEX), naphthalene, polynuclear aromatic hydrocarbons
<br /> (PAHs), specific conductivity (EC), total dissolved solids (TDS), nitrate (NO3), and general
<br /> minerals (boron, calcium, hardness [as CaC031, iron, magnesium, manganese,potassium,
<br /> sodium, chloride, sulfate, phosphate,phosphate, alkalinity [as CaC031, and bicarbonate [as
<br /> CaC031) shall be analyzed in the influent samples weekly for the first three weeks of treatment;
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