SITE INFORMATION AND CORRESPONDENCE

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Dopaco Inc. (Case 1 Tank C) -3 - 15 April 2015 800 W. Church St., Stockton San Joaquin County 7) In September 1986 all eight USTs (A through H) in the Dopaco area were removed. The contents of the LISTS are listed in Table 1 of Finding 1. The 21 October 1986 Underground Tank Removal Report submitted by American Environmental Management Corp. stated maximum confirmation soil concentrations were: benzene, 16 micrograms per kilogram (ug/kg), toluene, 36 ug/kg; and total petroleum hydrocarbons as diesel, 330 ug/kg (0.33 milligrams per kilogram) by USEPA Method 8015 and 8020. Later sample analysis utilized USEPA Method 8260B detecting 1,4-dichlorobenzene, 4-methyl-2-pentanone, isopropylbenzene and carbon disulfide in addition to petroleum constituents in groundwater underlying the Dopaco Area (see results in attached Tables 3 and 4). 8) In a letter dated 24 March 2012, the SJCEHD formally referred the Site to the Central Valley Water Board. SJCEHD cited a pending Stipulated Injunction and Consent Decree (Court Order) between Dopaco Inc. and The Newark Group, Inc. as the rationale for the referral. The 20 April 2012 Court Order provided the boundaries for the Dopaco Area (Figure 3, Boundaries of Court Order) and required Dopaco Inc. conduct a Toluene investigation and cleanup under Central Valley Water Board oversight on The Newark Group Inc. property. A copy of the Court Order is included as Attachment A. Cascades Inc., a Canadian corporation dissolved its subsidy Dopaco Inc. in 2012, and became the sole responsible party in the Court Order. 9) The 11 September 2012 Preliminary Data Evaluation Report and Recommendations for Monitoring Wells (Report) documented Cone Penetrometer Testing (CPT) soil borings, using Membrane Interphase Probe (ionization detectors), and a grab groundwater investigation to help locate four (4) proposed monitoring wells. In the Report, EG stated Toluene was detected in soil gas in the Dopaco Inc. LISTS source area. The soil gas data from the CPT Investigations in 2012 and subsequent CPT and Direct Push investigations in 2013 were used to design the over-excavation required in the Court Order. The groundwater results of the Direct Push investigation are given in Table 2 below. Table 3: Maximum Grab Groundwater Concentrations in micro rams per Liter ug/L) Toluene 1,4- 2 Butanone 4-Methyl-2- Acetone Cis-1,2- Vinyl Chloride Dichlorobenzene Pentanone Dichloroethene 500,000 0.9 170,000 340,000 110,000 9.0 3.0 Water Quality Water Quality Water Quality Water Quality Water Quality Water Quality Water Quality Goal Goal Goal Goal Goal Goal Goal 150 5.0 4,000 120 6,300 6.0 0.5 1 =Primary Maximum Contaminant Level 2=USEPA Advisory 3=California Notification Level 4=USEPA IRIS Reference Dose 10)A work plan to install four (4) shallow groundwater monitoring wells was approved with conditions on 18 September 2012, but only three wells (DMW-1 through DMW-3) were initially installed (Figure 5, Monitoring Wells with Extent of Toluene Pollution). Subsequently one shallow and one deep (DGW-5 and DGW-5D) monitoring wells were installed in the Toluene source area after over- excavation of the Site. In June 2014, three additional monitoring wells (DMW-6A, DMW-6B, and DMW-6WT) were installed to the north of the Site across Church Street in the downgradient direction to delineate the extent of impacts from the Toluene release. Dopaco Inc. conducted seven (7) events of groundwater monitoring from December 2012 to December 2014. Groundwater monitoring results provided in the attached Table 2, indicate a plume length of less than 50 feet with a declining concentration trend. 11) In February 2014, a 285 square foot area of the Site (east of Tanks A through F), was over- excavated from ground surface to 30 feet below ground surface (' bgs) ( see Figure 6, Site Layout