SITE INFORMATION AND CORRESPONDENCE

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Mr. Allan Fetters and Mr. Bud den Ouden - 3 - 30 September 2009 water end uses include irrigation of City-owned parks and process water for specific industries. Before the aquifer test begins, RF Land, Inc. and Ripon Farm Service, LLC must verify the nitrate limits that the City of Ripon will accept into the non-potable system, and identify where the water will be physically transferred into the non-potable system. If RF Land, Inc. and Ripon Farm Service, LLC select an alternative disposal option, it needs to obtain concurrence from Central Valley Water Board staff prior to discharge. Isotope Analyses Groundwater analyses providing nitrogen and tritium isotope ratios could provide information that may determine the sources of nitrogen, and the interconnectivity of the shallow and deep groundwaters. The Revised Work Plan proposes nitrogen and tritium isotope analyses from two off-site shallow and deep well pairs (RMW-1 SR and -1 D and RMW-3S and -3D) and from the shallow on-site extraction well. In order to identify if there are differences in isotope ratios between two bodies of water. or to distinquish between environmental sources of nitrogen while accounting for denitrification, enough samples need to be obtained to be able to plot the data. For this data to be meaningful, at least five samples should be obtained for analysis from different locations in the shallow aquifer and at least five samples should be obtained from different locations in the deep aquifer. Isotope analyses used to distinquish between sources of nitrogen should also include the oxygen isotope of nitrate, as well as the nitrogen isotope of nitrate. This permits the data to be compared to existing data sets that compares isotope results with known sources of nitrogen. Central Valley Water Board staff conditionally concur with the Revised Work Plan, subject to the following changes. • Before disposing of aquifer test water, provide assurance that the water quality and delivery location is acceptable to the City of Ripon or that an alternate disposal location is acceptable to Central Valley Water Board staff. • Provide a Work Plan Addendum that provides the following: an updated figure that indicates a deep boring near the western surface water sump area and the proposed locations of two monitoring wells extending to the water-bearing zone encountered at about 190 feet bgs; proposed construction methods for two deep monitoring wells. • All shallow and deep borings, monitoring wells. and the extraction well shall be installed to the satisfaction of San Joaquin County Environmental Health Department. Please submit the Work Plan Addendum for Central Valley Water Board staff concurrence by 6 November 2009, prior to implementing the field work. The field work must be conducted prior to 20 November 2009, and a report of results must be provided by 29 January 2010.