SITE INFORMATION AND CORRESPONDENCE

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Gene Gabbard Inc. - 2 - 9 July 2009 640 N. EI Dorado St., Stockto� • , r In June 2001, free product was observed in MW-3. Beginning in September 2001, weekly hand bailing of MW-3 was initiated and later reduced to twice per month to remove free product. In April 2003, a passive oil skimmer was installed in MW-3, which operated until April 2005, when an automated belt skimmer replaced the passive oil skimmer. Approximately 90 gallons of mixed free product and water were removed by skimming from MW-3. Skimming stopped in June 2006 after free product was no longer present in MW-3. In May 2003, three additional monitoring wells (MW-5 through MW-7) were installed and three additional borings were advanced to determine the subsurface lithology, to investigate the extent of the PCE plume suspected as part of the UST release, and to map potential preferential pathways. Quarterly monitoring of MW-7, located on the northwest corner of the property and crossgradient to groundwater flow direction, consistently reported PCE at the highest concentrations throughout the groundwater monitoring. In 2005, the consultant suggested that a leaking City of Stockton sewer located under EI Dorado Street and a drycleaners located one block to the north of the Site were the source of the PCE in groundwater. Petroleum hydrocarbons groundwater concentrations continued to decline over the years; however, all work stopped in June 2006 when the State Water Resources Control Board UST Cleanup Fund (CUF) stopped payment of the claim and demanded repayment after determining the PCE plume was due to an offsite source not related to the UST. The SJCEHD and Regional Board staff met with the owners, tenants, an attorney, and the consultant in March 2008, in an attempt to move the case towards closure. On 13 June 2008, SJCEHD referred oversight lead of the subject case to the Regional Board for enforcement action due to non- compliance with SJCEHD directives. The Regional Board Executive Officer issued a 13267 Order to the responsible parties on 1 August 2008, which required monthly status reports while the CUF payment issue was being resolved, resumption of quarterly monitoring by fourth quarter of 2008, and submittal of the chain of title for property ownership and UST operations. Since November 2008, the responsible parties have complied with the 13267 Order. The 3 September 2008 Third Quarter 2008 Groundwater Monitoring Report analyses showed that only MW-3 contained petroleum hydrocarbons at the following concentrations: TPHmo, 520 ug/L; TPHg, 460 ug/L; benzene, 8.2 ug/L; toluene, 2.4 ug/L; ethylbenzene, 5.8 ug/L; xylenes, 14 ug/L; methyl tert-butyl ether (MTBE), 0.6 ug/L; and 1,2-dichloroethane (1,2-DCA), 1.6 ug/L. Since water quality conditions had not degraded further during the three years groundwater monitoring hiatus, groundwater monitoring was suspended 1 December 2008 pending our case closure review. Depth to groundwater varied from 21' to 27' below ground surface, while groundwater flow direction was towards the northeast at 0.003 feet/feet. Soil vapor intrusion concerns were adequately addressed in the September 2008 Status Report. The 1998-1999 confirmation and boring soil samples exceeded the Region 2 Environmental Screening Levels (ESLs) for gross contamination, however due to the depth (15 feet bgs), and that the site is cover by concrete and buildings, and continued natural attenuation the residual impacts do not pose a threat. Property zoning (commercial) and land use is not expected to change in the foreseeable future, as the Site is outside of the Stockton downtown redevelopment zone.