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ii a k' 65 eline soil samples. toluene concentrations detected in the pip These concentrations ranged from 0.036 mg/Kg to 0.32 mg/Kg. WESTON noted in our November 7, 1989 report that these concentrations are two orders of -magnitude less than the designated level of 100 mg/Kg (Section 4.2 of November 7, 1989 Report) . In discussions with WESTON, Mr. Lyons asserted that these levels are above the state action level value of 0.1 mg/L. Mr. Lyons was i,ifnrmed that this is the action level for drinking water. In order tc, determine the designated level (and accordingly the cleanup level per the CRWQGB, cvR staff report, source 2) the action level is multiplied by the attenuation factor and the compound leachability factor. For this case, WESTON utilized a " "generic" soil attenuation factor of 100 as recommended in source 2, section 3.3.1. WESTON also utilized source 2 to obtain a leachability factor (called the bio-availability factor) of 10 for toxic organic constituents. Subsequently, the designated level calculation would appear as follows: 0.1 mg/L x 100 x 10 = l00 mg/Kg Per the information contained in section 3.3.1 of source 2, th n mg/L converts through th=s equation to mg/Kg. 41 'a As can be seen by this equation, the designated level for toluen- at the site is 100 mg/Kg. 5.0 Tank T1 The issue raised by Mr. Lyons regarding Tank T1 was in reference to �., the total lead concentrations detected within the soil samples from beneath the tank. The total lead concentrations were 54.2 mg/Kg and 61.3 mg/Kg. A" In WESTON's November 7, 1989 report, mention was made that these concentrations fall below the designated levels of 1 g/Kg and 500 mg/Kg as obtained from sources 1 and 6. Mr. Lyons stated that his impression was that a problem existed within this area regarding the lead concentration. WESTON does not agree with this assessment. As can be seen by the " two designated levels referenced above, there does not appear to be a lead problem. This can be supported by following the rationale presented for toluene in se:tion 4.2 of this report. _ The designated level for lead as calculated utilizing the methodology presented within source 2, with an attenuation factor factor 100 (for of 100, a leachability ersource toxic inorganic 3, would. be- as constituents) and an MCL of 0.05 mg/L p follows: --- - - - --- ---- -- - 0.05 mg/L x 100 x 100 = 500 mg/Kg