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Mr.Harlin Knoll Environmental 22 October 2013 Resources Page 2 Management The two USTs were used to store gasoline and were removed from the facility on 18 February 1998. The tanks were located approximately 600 feet from one another (Figure 2). As seen in Figure 2, the tank designated as "UST 1" was located on the western side of the property and the UST designated as "UST 2" was located on the eastern side of the property. Releases of petroleum hydrocarbons from both USTs were detected during the UST removal activities. Petroleum-impacted soil and i•� groundwater were subsequently removed from the excavation at each former tank location. A soil and groundwater investigation, including the installation of monitoring wells, was conducted at each former tank site to determine the extent of the petroleum impacts. Groundwater remediation activities were subsequently conducted to reduce the concentrations and extent of petroleum hydrocarbons in groundwater downgradient of each site. Ongoing groundwater monitoring indicates that the residual levels of petroleum hydrocarbons at the two locations have decreased significantly since the beginning of monitoring. On behalf of Heinz, ERM prepared a Site Closure Report dated 5 December 2011. The report presented data to support the site meeting required qualifications as a low-risk case. Based on the data, Heinz requested that the State issue a uniform closure letter. Based on discussions with the County concerning the Site Closure Report, ERM prepared a Site Closure Report Addendum dated 17 January 2013 for submittal to the County. The addendum provided additional data and analyses to support site closure as requested by the tCounty. In a letter dated 3 May 2013 from the County to the Central Valley Regional Water Quality Control Board (CVRWQCB), the County presented a "Case Closure Summary" for the site. The letter indicated' that the County determined the site investigation and remedial action for contamination resulting from the release had been completed, and requested concurrence from the CVRWQCB for no further action. The CVRWQCB submitted a letter to the County dated-22 May 2013, indicating they concurred with the County's recommendation for case Cclosure.