SITE INFORMATION AND CORRESPONDENCE

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Mr. Allan Fetters and Mr. B den Ouden - 2 - 30 September 2009 • Five deep borings sampled for nitrogen about every 20 feet extending to the depth of the on-site water supply well; which is about 195 feet bgs. • A groundwater extraction well terminating in the shallow water-bearing zone. • An aquifer pump test for characterization of the shallow water-bearing zone. • Isotope analyses will be conducted on shallow groundwater samples obtained from two off-site shallow monitoring wells, two off-site deep monitoring wells, and the on- site extraction well. Central Valley Water Board staff have the following comments and conditions on the Revised Work Plan. Shallow and Deep Borings The borings will provide information about the stratigraphy and the nitrogen distribution at the site. The work plan indicates that one of the shallow borings will be positioned near the western surface water sump. The sump is a suspected source area for nitrate pollution, and RF Land Inc. and Ripon Farm Service LLC need to replace the shallow boring with a deep boring at this position. After samples have been obtained, the shallow and deep borings need to be sealed with grout to the surface. Deep Monitoring Wells Nitrogen pollution has been identified at about 190 feet bgs at the location of the destroyed on-site water supply well. In order to obtain repeatable sampling points at this depth, RF Land, Inc. and Ripon Farm Service, LLC need to install at least two monitoring wells on-site that intersect this water-bearing zone. One of the monitoring wells should be in the vicinity of the liquid containment areas. RF Land, Inc. and Ripon Farm Service, LLC need to provide a Work Plan Addendum that identifies proposed locations and construction methods for the deep monitoring wells. Extraction Well and Aquifer Test The six-inch extraction well will be installed into the shallow water-bearing zone and located near the batch plant. The Revised Work Plan did not identify how the annular space will be sealed. The annular space should be grouted per San Joaquin County Environmental Health specifications. Existing monitoring wells MW-103 and CRW-4 will be observation wells. In addition. the nearest on-site deep monitoring well, as required in the above section, should also be used as an observation well. This will assist in determining if there is connectivity between the shallow and deeper aquifers. Discharge water will be collected in Baker tanks, characterized, and is proposed to be delivered to the non-potable water distribution system operated by the City of Ripon. This non-potable water system distributes groundwater that contains nitrate above the maximum contaminant level. It does not convey treated wastewater. Non-potable