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Appendix E.1:Data Usability Summary A summary of qualified data is provided in Table E-1. Data validation reason codes for all qualified data are also presented 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 matrix spike/matrix spike duplicate (MS/MSD)pairs provided information on the precision of sampling and analytical procedures. The RPDs for laboratory control sample 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. LCS/LCSD s An LCS was analyzed with each analytical batch of samples. An LCSD was analyzed with some batches of samples. The %Rs for all LCS and LCSDs were within the laboratory control limits with the following exceptions: • The %R for benzo(a)pyrene was above the laboratory control limit in the LCS analyzed with water samples in Report 1170491. Benzo(a)pyrene was detected in one associated sample, the equipment blank QA-Tubing-R-091110. The result was qualified E for a potential high bias. • The %R for phenanthrene was above the control limit in the LCS associated with soil sample SB-41-S-22-091116. The result was qualified E for a potential high bias. • The %Rs for naphthalene was above the control limit in the LCS associated with groundwater sample SB-38-W-091112. The result for naphthalene was non-detect and no data were qualified. • The %Rs for 1-methylnaphthalene and acenaphthene were above the control limits in the LCS associated with groundwater sample SB-38-W-091112. The sample was re- extracted outside the method holding time and 1-methylnaphalene was detected again. Acenaphthene was not detected in the re-extracted sample. The result for 1- methylnaphthalene was not qualified because the original result was confirmed by the re- extraction. Acenaphthene was qualified E because the result was not confirmed. Surrogates Surrogate recoveries were evaluated for all methods. All surrogates were within laboratory control limits, with one exception. The surrogate orthoterphenyl, used in the analysis of TPHd was above the control limit in one LCS. The recovery for diesel in the LCS was within the control limits, and therefore the surrogate recovery did not indicate an associate bias. No data were qualified. Nitrobenzene, one of the surrogates used in the analysis of PAHs, and chlorobenzene, one of the surrogates used in the analysis of TPHc, were not assessed for these data. The compounds are not associated with the target analytes reported for this data set. The other surrogates used in the analyses are more appropriate to use for assessing accuracy of the analyses. Surrogates were also not evaluated if the sample was diluted by a factor of 10 or greater. In these cases, the surrogates are considered"diluted out" and not used to assess the accuracy of the analysis. E.1-3 —– =— Frain Science to Solutions