SITE INFORMATION AND CORRESPONDENCE

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Moore Truck Lines - 2 - 25 May 2012 3400 Newton Road Stockton, San Joaquin County Date TPHg TPHd TPHmo B T E X MTBE 1,2-DCA PCE TCE 1-99 29,800 11,400 <250 14.9 1,370 245 2,490 9.1 NA 0.22 <0.0005 2 6-99 1.6 <5 <5 0.075 0.009 0.033 0.20 5.2 NA NA NA 9-01 <1 <1 <1 <0.005 <0.005 <0.005 <0.005 <5 <5 NA NA 4-04 <1 <10 I <10 <0.005 <0.005 <0.005 <0.005 <10 <5 NA NA 6-08 1 2.2 NA I NA <0.005T<0.005 <0.005 <0.005 0.220 1 <0.005 NA NA TPHg=total petroleum hydrocarbons as gasoline TPHd=as diesel TPHmo=as motor oil B=benzene T=toluene E=ethylbenzene X=xylenes MTBE=methyl tert butyl ether PCE=tertrachloroethene TCE =trichloroethene 1 =confirmation soil samples 2=lab footnoted as primarily motor oil range 3=CPT-1 4=boring MW-7 5=boring MW-8 Maximum results of groundwater investigations, reported in micrograms per Liter (ug/L), are summarized in the table below. Date Media TPHg TPHd B T E X MTBE TBA 1,2-DCA TAME 6-99 grab water 2,400 NA 19 10 13 170 160 NA NA NA 11-99 water 970 NA <0.5 <0.5 <0.5 <0.5 37 <5 NA <1 6-00 water 600 NA 3.8 0.98 <0.5 0.55 13 10 NA <1 2-02 water 420 140 1.0 1.3 <0.5 0.64 10 <1 22 <1 6-02 water 330 210 2.1 0.81 1.0 2.7 180 <50 22 6.4 4-04 grab water" <50 <50 <0.5 <0.5 <0.5 <0.6 <1 <10 <1 <1 6-07 water 700 NA <0.5 <0.5 <0.5 <0.5 630 <10 3.2 45 2/08 water 400 NA <0.5 <0.5 <0.5 <0.5 390 NA <1 <1 2-11 grab water <50 NA <0.5 <0.5 <0.5 <0.5 <0.5 NA NA NA 3-11 water 140 NA <0.5 <0.5 <0.5 <0.5 120 NA NA NA 8-11 water 800 NA 1 <0.5 <0.5 <0.5 <0.5 590 NA NA NA 1 =groundwater results from MW-1 with standard purging. Note MW-1 is often dry while deeper(but screened across water table) adjacent MW-8 water results are non-detect 2=CPT-1 grab water 3=insufficient water in MW-1 to purge,sample taken as grab 4=MW-1 purged dry at 0.4 gallons,took over 1 hour to recharge up 1 foot in well. One of the two Site domestic wells, DW-1 (140' northeast of MW-1) was sampled from 2000 to 2008, and all results were non-detect for petroleum hydrocarbons. The second Site domestic well, DW-2 (60' east of MW-1) reported low levels of TPHd (280 ug/L), toluene (1 ug/L), and xylenes (1.1 ug/L) in October 2000. DW-2 was properly destroyed in December 2000. The seven monitoring wells around MW-1 (MW-2 through MW-8) and onsite domestic well (DW-1) sample results were non-detect when sampled, indicative of a limited source of contamination in soil at MW-1. MW-1 has reportedly been dry or contained inadequate water to purge through much of the investigation, due to a drop in water levels since installation in 1999. MW-1 is screened from 44' bgs to 63' bgs in silty clay, and does not recharge quickly when,dewatered; resulting in elevated groundwater concentrations when compared to adjacent (10' to the southeast of MW-1) MW-8 (screened 60' to 70' bgs) which had been non-detect for petroleum hydrocarbons from