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2.2 Primary Source Data regarding the primary source of the petroleum hydrocarbon residuals in soil and groundwater is linuted Available data (groundwater monitoring and site soil chemistry) indi- cate that the primary sources of petroleum hydrocarbons were the former product storage and piping facilities Additionally, a relatively recent source of hydrocarbons at the site appears to be associated with product delivery activities These conditions have since been rectified Based on available information, it appears that there are no primary sources of hydrocarbons at the site 2.3 Secondary Source Secondary sources of residual petroleum hydrocarbons beneath the site were identified as (1) groundwater containing dissolved petroleum hydrocarbons, and (2) capillary fringe soils containing absorbed hydrocarbons Although not addressed by this CAP, it should be noted that volatile organic compounds (VOCs) have been identified beneath the site The source of these VOCs is presumably located within Lincoln Center as previously discussed Vadose zone hydrocarbon impact appears negligible based on soil samples collected during the installation of the seven on-site wells (MW-1 through MW-7) Analyses of soil samples collected at 5-foot depth intervals from these wells did not reveal hydrocarbons These samples were collected at depths ranging from 5 to 65 feet below ground surface (bgs) Hydrocarbons were detected in soil samples collected in the former tank complex excavation These hydrocarbons, however, appear to be limited to soils directly underlying the former USTs and are not laterally or vertically continuous This conclusion is based on the results of soil samples collected during the drilling of Well MW_1 located directly within the former tank complex and the results of other soil samples that were collected in the tank excavation The absence of detectable concentrations of hydrocarbons within the capillary fringe soils is typical due to the low concentration of dissolved hydrocarbons detected in groundwater Dissolved hydrocarbon impact on site (with the exception of Well MW-2) is of low concen- tration In many cases the dissolved total petroleum hydrocarbons calculated as gasoline (TPH-g) and VOCs are mixed Where mixtures of the two compounds are present, an increase in the reportable concentrations is common In respect to Well MW-2, this well is located along the downgradient property boundary and downgradient of the existing USTs Groundwater samples collected from this well contain slightly elevated TPH-g and benzene concentrations (TPH-g 630 and 150 parts per billion [ppb]) Data infers that dissolved TPH-g found in Well MW-2 may be a result of a limited source of hydrocarbons at the existing UST complex 1,2-D ichl oro ethane (1,2-DCA), 1,1-dichloroethane (1,1-DCA), and trichloroethene (TCE) occur beneath the site at relatively low dissolved concentrations as do elevated concentrations 3201357BICAP 3 April 4, 1995