SITE INFORMATION AND CORRESPONDENCE

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Mr. Robert Granberg , - 2 - • 25 May 2010 You should familiarize yourself with the contents of the WOO. The groundwater discharge activity must be operated in accordance with the requirements contained in this Notice of Applicability (NOA) and WOO, with the information submitted in the NOI and additional information, and be monitored in accordance with the attached Monitoring and Reporting Program (MRP). DISCHARGE DESCRIPTION The pipeline alignment and LAA locations are presented on Attachment A, which forms part of this notice by reference. Dewatering will be performed along Empire Tract, King Island, and Bishop Tract. Only the groundwater originating on Empire Tract will be applied to land under the authority of this NOA. Groundwater originating on King Island or Bishop Tract will be discharged to the City of Stockton wastewater collection system. The tunnels that will be constructed under Honker Cut and Bishop Cut will be constructed using a "water-tight" method of shaft construction that will result in a small amount of groundwater to be disposed of. That groundwater will be pumped into water trucks and delivered to the City of Stockton's wastewater collection system. The LAAs are owned by two entities. The Discharger has submitted written agreements with the landowners for the groundwater application activity. Berms will be added to the LAAs as needed to ensure applied groundwater does not runoff. The LAA names and acreages are listed below: Land App. Area Acreage Suprenant 123 Woody's on the River 436 Preliminary Site Assessment As part of the project design, a 7 April 2008 Phase I Environmental Site Assessment (ESA) was prepared by Camp, Dresser, and McKee, Inc. (CDM). A petroleum fuel leak site at Herman and Helen's Marina was identified as a potential source of contamination near the pipeline construction alignment. No other chemical leak sites were identified in the ESA. Because methyl t-butyl ether (MTBE) is present in the Herman and Helen's groundwater plume, the potential for dewatering to affect the plume was reviewed. MTBE's physical properties - adsorbs weakly to aquifer materials resulting in limited retardation and resists degradation in ground water, made it the constituent of concern in the analysis. A hydrogeologic investigation performed at Herman and Helen's Marina revealed the following: a "shallow aquifer zone" approximately 25 feet thick is underlain by a low permeability aquitard approximately 10-15 feet thick, below which exists the "deep aquifer zone," which is at least 60 feet thick. Because dewatering will occur in both the shallow and the deep aquifer zones, the effect of dewatering, including potential changes to vertical gradients across the aquitard, was analyzed by CDM. CDM prepared a groundwater model that assessed the impact of the dewatering activities at the Herman and Helen's groundwater plume. The model estimated a 0.5 foot groundwater elevation decrease in the shallow zone as a result of the groundwater dewatering. To