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1 <br /> ' DRAFT <br /> ' Input parameters used to calculate chronic daily intake and noncarcinogenic hazards and <br /> excess cancer risks are presented in Table 17. Algorithms used to calculate chronic daily <br /> intakes and non-carcinogenic hazards and excess cancer risks for the receptors evaluated <br /> are presented in Table 18. <br /> 1 <br /> Chemical data for soil and groundwater samples used in this risk assessment was <br /> ' provided by Treadwell and Rollo in summary tables. It was assumed that the data was <br /> valid and accurately compiled for purposes of conducting the human health risk <br /> ' evaluation. The 95%UCL or the maximum concentration of each COC, as appropriate, <br /> was used to estimate the exposure point concentration in soil and groundwater. In those <br /> cases where less than six laboratory data results were available, the maximum <br /> concentration of each COC was used for the exposure point concentrations. <br /> At sampling locations where a COC was not detected (ND), it was conservatively <br /> ' assumed that the chemical was present at one-half of the detection limit. Therefore, the <br /> 95%UCLs for each chemical have been calculated from the sum of both detected <br /> concentrations and proxy concentrations. <br /> 1.4.1 Noncarcinogenic Hazard <br /> For the noncarcinogenic evaluation, the representative concentrations for each of the <br /> 1 respective COCs were used to estimate chronic daily intakes (CDI). Chronic daily <br /> intakes (CDI) for each of the potential receptors (both a child and an adult were estimated <br /> 1 separately for the residential scenario)were calculated for each applicable route of <br /> ' exposure. The calculated CDI for each COC was then divided by its respective RfD <br /> (based upon a noncarcinogenic endpoint) to yield a chemical specific hazard quotient <br /> (HQ). The HQs calculated for each COC were then summed to yield a hazard index (HI). <br /> For the residential scenario, hazard indices are evaluated separately for the child and <br /> adult, with the child HI representing the more conservative risk value. <br /> SOMA 99-2218 12 12/10/99 <br />