SITE INFORMATION AND CORRESPONDENCE

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T - f Mr. Matt Gabris L/ `/ Page 2 of 3 Earth Grain/former Kilpatrick Bakery September 28 2009 1717 S. Center Street, Stockton, California 3. As noted in the EHD correspondence dated March 18, 2009, other than the nearby presence of a underground storage tank (UST) that may, or may not have had a release, no data and sampling points are available to demonstrate that the groundwater contamination in deep monitoring well MW-5A is not related to the groundwater contamination in MW-2A; in fact, the opposite case is supported by the grab groundwater data from boring C-8. The EHD had required at least one additional monitoring well to be installed at the same depth and between MW-2A and MW-5A and the work plan required to address this concern has not been submitted. The groundwater plume is not fully characterized and you have not demonstrated the relationship between the core wells and the well north of the core. With the lateral extent of the plume not fully characterized, the site does not qualify for a no further action status. 4. The lower limits of the plume core shown on Figures 5 through 8 of the NFAR are not supported by data; they illustrate an untested plume model. The EHD cannot accept these figures as definitive interpretations of the limits of the plume or as likely characterizations of the lithological boundaries of the subsurface material. Based on the items noted above, your request for no further action is denied. This decision is subject to appeal to the State Water Resources Control Board (SWRCB), pursuant to Section 25296.40(a)(1) of the Health and Safety Code (Thompson-Richter Underground Storage Tank Reform Act — Senate Bill 562). Please contact the SWRCB Underground Storage Tank Program at (916) 341-5752 for information regarding the appeal process. In addition, PSC's conclusion that the abandoned UST present on the parcel directly to the north of the site near monitoring wells MW-5 and MW-5A is a source of contamination to the subject site has not been demonstrated. The EHD considers that the lack of groundwater contamination in the shallow, first interface monitoring well closest to the abandoned UST (MW-5) and elevated levels of petroleum detected in the deeper monitoring well at this location (MW-5A) indicates that this UST may not be a source of groundwater contamination in this area. Contaminants in MW-5A may be a result of migration from Earthgrain's UST site as supported by groundwater data from MW-2A and boring C-8. No technical data or explanation was provided in the NFAR to support conclusions that the abandoned UST is contributing to the groundwater contamination in MW-5A, but is somehow not impacting MW-5. Please submit a work plan to Geotracker, in the context of the site conceptual model (SCM), by 30 October 2009 to continue the assessment of the vertical and lateral extent of groundwater impact encountered in MW-2A. The work plan should address the installation of a monitoring well midway between MW-2A and MW-5A that is screened in the same hydrogeologicai unit to further evaluate that relationship of CDCs in MW-2A to those in MW-5A. Include laboratory analysis for 1,2-dichloroethane (DCA) and ethylene dibromide (EDB) in groundwater samples from the new deep well for two consecutive monitoring events. 1717 Center NFAR denial CML 9-28-09