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v f While no definitive limit has been established for in-place petroleum hydrocarbon compounds, the cleanup criteria for the 'ite of 100 mg/kg TPH was selected based on discussions with the San Joaquin Local Health District, the known site conditions and the lack of domestic wells in the vicinity of a the site. This alternative is feasible due to the limited area which will require excavation, the accessibility of the area and the remediation deadline required in order not to delay construction (July 1969) of the Human services Build- Ing. B. In-Situ Volatilization �s �.r While this is a plausible alternative, several factors weigh against the selection of this alternative for the site. ISV systems are expensive and require a great deal of soil. characterization information and testing. In addition, the permitting process for such systems can be lengthy. This alternative was not selected due to cost and time re- straints. C. In-Situ Flushing This alternative would require saturating the soils and extracting the flush water. Because this alternative is subject to the same restraints as presented for alternative ., B, in-situ flushing was not practical for the site. ` Based on time constraints, costs and the limited extent of the compound presence, Alternative A, excavation of soils in excess of 100 mg/kg TPH was selected as the preferred remedial action. Regarding the hydrocarbon presence in the groundwater, several factors such as the economic feasibility of groundwater treat- ment, beneficial aquifer uses, aquifer flow and compound thresh- old limits were assessed. No active remedial measures are proposed for the site. As discussed in the Problem Assessment Report (Section 6.0) , the State of California Leaking Underground Fuel Tank Field Manual was utilized to select the appropriate remediation path. Due to the lack of free product, the limited nature of the dissolved product, and the prohibitive costsof groundwater treatment, it is proposed to conduct a limited pump test to determine aquifer yield; thereby determining the i { usability of the aquifer. # ' 3.0 REMEDIAL PROJECT DESCRIPTION 3.1 Excavation As hydrocarbon compounds within the soil appear to be centralized around borehole #3 (Figure 2) , it is proposed that a stepped excavation be conducted at the site with the lower limit of the r . e.