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Data Usability Summary • Completeness • Comparability DATA USABILITY SUMMARY The following sections summarize the findings of the data evaluation process. A summary of qualified data with reason codes is provided in Table B-1. Data validation reason codes for all qualified data with the associated reasons for qualification are also presented and defined on Table B-1. The following data validation qualifiers were used in the data evaluation: ualifier Description E Indicates the reported value is estimated due to associated quality control results. J Indicates the reported value is an estimated concentration detected between the method detection limit(MDL)and limit of quantitation (LOQ). Precision and Accuracy The precision and accuracy of field and laboratory QC samples were evaluated. The calculated relative percent differences(RPDs)for field duplicate and matrix spike/matrix spike duplicate(MS/MSD)pairs provided information on the precision of sampling and analytical procedures. The RPDs for laboratory control samples and laboratory control sample duplicates(LCS/LCSDs)provided information on the precision of the analytical procedures. Evaluation of the percent recoveries(%Rs) of MS/MSDs, LCS/LCSDs, and surrogates provided information on accuracy. All surrogate%Rs were within the required laboratory control limits. LCS/LCSDs A LCS and LCSD were analyzed with each analytical batch of samples. The%Rs and RPDs were within the laboratory control limits,with the following exceptions: the%Rs for benzo(g,h,i)perylene and indeno(1,2,3-cd)pyrene were 120 and 122 percent,respectively,in the LCS,which exceeds the control limit of 117 and 119 percent. The expected bias in associated sample results is high and detected in samples MW-6-W-061107MS and MW-6-W-061107MSD therefore,these samples qualified as E. MS/MSDs Project-specific MS/MSD samples MW-6-W-061107MS and MW-6-W-061107MSD were collected with the field samples evaluated for this report. The%Rs and RPDs for the MS/MSD samples were within the required control limits with the following exception:the%R for dibenzo(a,h)anthracene was 124 percent for the MS and 121 percent for the MSD,which is above the 119 percent QC limit; and the%R for indeno(1,2,3-cd)pyrene was 117 for the MS which is above the 116 percent QC limit. The expected bias in associated sample results is high and detected in sample MW-6-W-061107MS and MW-6-W- 061107MSD therefore,these samples qualified as E. Representativeness Representativeness was assessed through the evaluation of method blank samples, trip and equipment blank samples, chain-of-custody forms,preservation, and holding times. Field QC Results One equipment rinsate blank was submitted with the samples. TPHd were detected in the equipment rinsate sample QA-R-061107 at 110 gg/L. TPHd was detected at 130 µg/L in sample MW-7-W-06110; therefore,this sample qualified as E.