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LEVINE•FRICKE ' Estimation of the relative age of the hydrocarbon samples was performed by evaluating organic lead concentrations, volatile ' constituents and the presence of polymerized derivatives compared between hydrocarbon samples and fuel standards. Organic lead ana- lysis was conducted on samples and unleaded and leaded fuel stan- dards by CAL. Samples for organic lead were subsequently analyzed by FFB as part of the Levine•Fricke quality assurance/quality control procedures. The chromatograms for hydrocarbon samples and fuel standards were prepared by CESC and evaluated by ' Levine•Fricke to assess the relative depletion of volatile con- stituents in the samples and the relative enrichment of dimerized derivatives that are often associated with aged fuels. ' Chemical Composition of Samples Chemical ionization mass spectra of the major peaks on the chro- matograms of the GC/MS analysis of the sample from SP-4 were ana- lyzed to identify the chemical constituents. The primary set of chromatogram peaks (front and middle constituents of the gas chromatogram) of sample SP-4 predominantly matches the constitu- ents detected in a gasoline standard provided by BCL. The chro- matographic peaks for characteristic aromatic derivatives (C7 and C8 compounds) of fuels were then identified from their ionization ' mass spectra and used as distinguishing indicator peaks between gasoline and JP-4. ' Fuel Composition of Samples Chromatogram characteristics including retention time and rela- tive areas of distinguishing peaks for samples and fuel standards analyzed by CESC were compiled by Levine•Fricke. Our evaluation of the chromatogram parameters for samples, gasoline and JP-4 standards, analyzed by CESC, are summarized in Table 1. The dis- tinguishing peaks of indicator constituents for JP-4 (65% gaso- line by composition) , including the relative amount of chemical constituents, are highlighted in Table 1. The secondary peaks (retention times greater than 23.43 minutes) in sample SP-2 were tentatively identified as components of diesel. Based on the results of our evaluation of the chromatograms of samples and fuel standards, the samples collected contain predominantly gaso- line. Diesel was a suspected minor constituent. JP-4 was not detected in the samples from SP-2 . ' The chromatograms of the SP-2 sample, standard diesel and gaso- line as analyzed by BCL were also evaluated by Levine•Fricke. Analysis of the chromatograms confirmed the CESC results that ' SP-2 was predominantly gasoline with a small amount of diesel. These same analysis methods were then applied to the samples from SP-3 and SP-4 with the same results - the fuel samples were pre- dominantly gasoline, the samples contained a relatively small quantity of diesel, and no JP-4 was present. -4-