SITE INFORMATION AND CORRESPONDENCE 1994-2010

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Weldon Church Property Page 2 104 West Beverly Place March 3, 2010 Tracy, California 95376 from the proposed well and monitoring well MW-4 prior to the applications, one week after each of the three applications, and weekly for one month following the final application. Prior to any application of RegenOxr"', AGE proposes to perform a water injection test to assess the aquifer's volumetric injection capacity limitations. To assess whether the proposed volume of RegenOxTM solution injected into the aquifer is feasible, AGE proposes to inject 365 gallons of potable water into MW-3 since the stratigraphy encountered at MW-3 is representative of the general site stratigraphy, and except for one sampling event when TPH-g was detected in groundwater at 100 micrograms per liter in December 2007, groundwater collected from this monitoring well has been free of contaminants of concern. AGE proposes to have the potable water proposed for injection analyzed for total petroleum hydrocarbons quantified as gasoline (TPH-g); benzene, toluene, ethylbenzene, and total xylenes (BTEX); methyl tertiary-butyl ether (MTBE), ethyl tertiary-butyl ether (ETBE), tertiary-amyl methyl ether (TAME), di-isopropyl ether (DIPE), tertiary butyl alcohol (TBA), 1,2-dichloroethane (1,2-DCA), and 1,2-dibromoethane (EDB) prior to injection to ensure that contaminants of concern will not be injected into the aquifer. AGE proposes to position the hose for injecting the potable water one foot from the bottom of MW-3 (at approximately 24 feet bsg); however this well, and monitoring wells MW-1, MW-2, and MW-4 are screened between five and twenty feet bsg, not five and twenty-five feet bsg, as indicated in reports submitted by AGE. The EHD conditionally approves the proposed preliminary aquifer volume test; however, the EHD recommends that borings advanced outside of the intended treatment area be used instead of MW-3 for performing this test. (Since MW-3 is screened from five to twenty feet bsg, the EHD does not understand how injections would be limited from five to twelve feet bsg, and thirteen to twenty/twenty-five feet bsg.) The EHD-proposed boreholes should be injected with water in the same manner proposed in the pilot test work plan for the application of RegenOxTM into each of the five proposed borings. Regenesis Technical Support has calculated 653 gallons for the total volume of water required for initial application into the clay layer, and 1,466 gallons for the total volume of water required for initial application into the silty-sand layer. Since AGE proposes to inject the two volumes among five boreholes, intuitively, it seems to the EHD that the total injection volume (653 gallons and 1,466 gallons) should be divided by five to equal 130.6 gallons and 293 gallons. Multiplying these two numbers by 1.25 (the factor recommended by Regenesis for calculating the volume of water to inject into the aquifer during the preliminary aquifer volume test), the EHD calculates that approximately 163 gallons of water should be injected from approximately five to twelve feet bsg (the clay layer) followed by injecting approximately 366 gallons of water from approximately thirteen to twenty-five feet bsg (the silty-sand layer). If this is correct, you may change the proposed injection volumes; if not, the volumes proposed by AGE should be used. Submit a site map to the EHD by April 15, 2010, showing the proposed location for the injection test boreholes and provide technical justification for selecting the location for this borehole. AGE proposes to install one monitoring well, screened between approximately five and twenty-five feet bsg, located approximately seven feet southeast of soil boring B18 where high concentrations of TPH-g and BTEX were detected in groundwater in June 2003. AGE