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Appendix E.1:Data Usability Summary • Precision • Accuracy • Representativeness • Completeness • Comparability DATA USABILITY SUMMARY The following sections summarize the findings of the data evaluation process. Immediately following is a summary of the data verification and validation qualifiers used in the data evaluation: ualifier Description E Indicates the reported value is estimated due to associated quality control (QC)results. J Indicates the reported value is an estimated concentration detected between the method detection limit(MDL)and limit of quantitation (LOQ). A summary of qualified data is provided in Table E-1. Data validation reason codes for all qualified data are also provided and defined on Table E-1. 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 MS/MSD pairs provided information on the precision of sampling and analytical procedures, and the RPDs for laboratory control sample/laboratory control sample duplicate(LCS/LCSD)pairs 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. MS/MSDs No project-specific MS/MSD samples were collected with the soil samples. However,the laboratory chose several soil samples to spike for MS/MSD samples, and all%Rs were within QC criteria. Project- specific MS/MSD samples were collected with the groundwater samples (SB-2-W-080317, S13-2-W- 080317MS, and SB-2-W-080317MSD). Anthracene, fluoranthene, and benzo(a)pyrene in either the MS or MSD had%Rs below QC criteria and were flagged E. LCS/LCSDs A LCS was analyzed with each batch of samples. All LCS/LCSD%Rs were within the laboratory control limits. Surrogates Surrogate recoveries were evaluated for all organic methods. The laboratory used three surrogates in the analysis of PAHS: nitrobenzene-d5, 2-fluorbiphenyl,and terphenyl-dl4. PAH surrogate nitrobenzene-d5 was above QC limits for several soil samples (SB-5-S-13-080318, SB-9-S-26-031908, S13-13-S-20- 080321, SB-14-S-23.5-080321, SB-21-S-5-080327, SB-21-S-6-080327, SB-21-S-7.5-080327, S13-21-S- 17-080327, SB-22-S-4.5-080327, SB-22-S-18-080327, and SB-22-S-25-080327). However, nitrobenzene-d5 is not associated with the target PAHS and was used to evaluate the overall system performance and not to qualify sample results. TPH surrogate chlorobenzene was above the QC limits for several soil samples(SB-13-S-20-080321, SB-14-S-23.5-080321, SB-15-S-19-080324, and S13-16-S-23- 080325). However, chlorobenzene was used to evaluate the overall system performance and not to qualify sample results. E.1-3 ori i wi From Science to Solutiens