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utilizing clean soil from nearby areas. Approximately 500 pounds of Oxygen Release Compound (ORC) were mixed with portions of the clean backfill and placed below the water table to address the groundwater impacts. Two areas of impacted soil were not removed during the excavation. These areas included the base of the excavation near the water table [to a terminal depth of 110 feet below ground surface (bgs)], and an area where excavation would have threatened the integrity of a standing structure. Bio-remediation methods were utilized to remediate the impacted soil stockpiles. Furthermore, additional soil sampling of the disposal area does not appear to have occurred. No further sampling details have been provided, and since the work was completed voluntarily with limited regulatory oversight, formal closure is unlikely to be granted by the San Joaquin County Environmental Health Department (SJCEHD). Based on the nature of the former release, likely presence of impacted soils remaining on the subject property and lack of closure documentation with the regulatory authority, the former use of the property as an asphalt plant represents a REC. According to a previous subsurface investigation conducted on a nearby property(10476 West Linne Road and San Joaquin County Case #RO0002070), the depth to groundwater in the vicinity of the subject property inferred to be approximately 78 to 87 feet bgs and groundwater flow inferred to be toward the northeast. Based on an on-site excavation during remediation activities, groundwater was encountered at the subject property at 110 feet bgs in 2004.The subsurface is expected to consist of sand, silt, and clay to at least 110 feet bgs. Objective The objectives of the project will be to identify the location of the remediation excavation and to evaluate the potential impact of petroleum hydrocarbons and/or volatile organic compounds (VOCs) to soil and/or groundwater as a consequence of a release or releases from the known subsurface impacts remaining in place, the stained soil, and the former stockpile area. To investigate the identified REC, Partner will conduct a Phase II Subsurface Investigation.The investigation scope will include a geophysical survey and the advancement of 11 borings to facilitate the collection and analysis of soil and/or groundwater samples. Refer to Attachment 1 for a map for proposed boring locations. The proposed investigation scope is designed to evaluate the objective. Based on the investigation results, regulatory conditions, and/or client requirements, subsequent investigation and consulting may be necessary. Scope Sampling procedures will generally conform to the requirements of SJCEHD, the State Water Resources Control Board (SWRCB), the Department of Toxic Substances Control (DTSC), and the United States Environmental Protection Agency(EPA). A state-certified laboratory will analyze the samples and the project will be performed under the responsible charge of a qualified Partner representative. Laboratory results will be compared to the San Francisco Bay Regional Water Quality Control Board (RWQCB) Environmental Screening Levels (ESLs). Partner will perform the following tasks for the Phase II Subsurface Investigation: Prepare a site-specific health and safety plan; Page 2 PARTNER