SITE INFORMATION AND CORRESPONDENCE

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J&L Market - 2 - • 8May 2013 8125 S. EI Dorado St., French Camp San Joaquin County The onsite domestic well (OSW, 40' from impacted JLM13) was initially sampled in 1995 and water results were reported as non-detect for TPHg and BTEX. The OSW, reported as not in use since 2000 when municipal water was connected at the Site, was recommended for destruction by the consultant in 2002. In January 2003, the OSW water was resampled and the water results were benzene, 0.65 micrograms per Liter (ug/L); toluene, 0.61 ug/L; ethylbenzene, 1.0 ug/L; and 1, 2-DCA, 1.6 ug/L. On 27 July 2004, the Regional Water Board Executive Officer issued a California Water Code Section 13267 Order to Submit Technical Reports that included submittal of reports for the OSW destruction and the additional groundwater investigation approved in December 2003 that was subsequently completed in December 2004. The OSW was properly destroyed in March 2005. Three Cone Penetrometer Testing (CPT1 through CPT3) borings were advanced in July 2005, and 1, 2-DCA was detected in grab groundwater samples at 130' below ground surface (bgs). In August 2005, four monitoring wells (JLM16 through JLM19) were installed to the east and southeast, offsite for lateral delineation. Seven monitoring wells (JLM20 through JLM26) were installed between October 2008 and December 2008, to complete onsite vertical delineation in the shallow, intermediate, and deep zones. Groundwater monitoring concentrations increased and peaked in 2004 (JLM13, 1, 2-DCA), in 2006 (JLM13, TPHg), and in 2007 (JLM13, BETX and TPHd). Maximum groundwater concentrations are reported in micrograms per Liter (ug/L) in the following Table. Date TPH TPHd B T E X MTBE TBA TAME 1, 2-DCA 11-95 ND NA ND ND ND ND NA <N k NA zD 11-01 2,300 NA 21 23 100 290 120 <1 40 6-02 2,000 NA 92 17 160 170 2.6 11 1-03 NA NA 0.65 0.61 1.0 ND ND ND ND 1.6 40 3-03 4,800 1,400 260 20 530 320 2.9 10 <0.5 4-04 910 300 43 5.4 140 25 . 5 0 5 6 15 5-05 3300 <0.5 11-04 300 <50 1.9 <0.5 5.2 7.5 <50 280 5.7 320 59 0.9 <5.0 <0.5 240 , 0.5 5 7-05 <50 <50 <0.5 <0.5 <0.5 <1.0 < <0. <0.5 18 <50 790 14 770 260 <0.5 <5.0 <0.5 300 5-06 7,300 5-07 390 6 <10 <100 <10 140,100 1,400 85 1,100 860 5-08 3,400 2,500 500 6.9 560 49 11 8 0 <0.5<0.5 16 6 5-09 4,200 3,300 540 7.7 660 79.7 1.7 23 <0.5 120 6-10 890 <50 13 1.7 73 32 1.4 19 <5 0 96 11-10 150 <50 2.5 <0.5 29 6.2 1.4 <5.0 <50 310 19 560 330 1.1 13 <0.5 150 122-1-1 4,100 1 1,900 <50 49 6.3 300 70 19 130 <0.5 140<0.5 17 3-12 660 <50 19 1.3 94 10 18 120 CR =t otal chromium Cr'= hexavalent chromium 1 =onsite domestic well ND=non-detect 2=grab groundwater 3=begin monitoring well results 4=CPT grab groundwater samples taken from 87'to 130'bgs 5=only JLM5 sampled;JLM13 1,2-DCA showed a slight decreasing trend after June 2011 but overall 1, 2-DCA is slowly declining since peaking in 2004(See Table 3,3'°Graph for 1,2-DCA data and trend) From December 2009 to January 2010, a remediation pilot test was conducted for ozone sparging (OS) using two ozone sparge wells (OS1 and OS2) installed near JLM13. The OS test was successful in reducing concentrations up to 89% in shallow groundwater. By November 2010, routine semi-annual monitoring showed groundwater concentrations were declining