ARCHIVED REPORTS_WELL ABANDONMENT, SOIL, AND GROUNDWATER SUPPORTING DOCUMENTS

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Appendix E.1:Data Usability Summary A summary of qualified data is provided in Table E-2. Data validation reason codes for all qualified data are also presented and defined on Table E-2. Precision and Accuracy The precision and accuracy of field and laboratory QC samples were evaluated. The calculated relative percent differences (RPDs) for MS/MSD and field duplicate pairs provided information on the precision of sampling and analytical procedures. The RPDs for laboratory control sample/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/LCSDs An LCS was analyzed with each analytical batch of samples. An LCSD was analyzed with some batches of samples. All LCS/LCSD %Rs were within the laboratory control limits with two exceptions: • The %R for anthracene was 67 percent,below the control limit of 70 percent, in the LCS associated with samples SB-18-S-5-080811, SB-19-S-5-080811, SB-18-S-59.5-080811, SB-18-S-40.5-080811, SB-19-S-37-080811, SB-20-S-5-080812, SB-20-27.5-080812, SB-20-S-40-080812, SB-21-S-5-080812, SB-22-S-5-0808012, and SB-23-S-5-080812. • The %R for benzo(a)anthracene was 79 percent,below the control limit of 80 percent, in the LCS associated with sample SB-22-W-080813, field duplicate SB-22-WD-080813, and equipment rinsate QA—Screen-R-080814. The recoveries for anthracene and benzo(a)anthracene were outside the QC windows, but within the marginal exceedence allowance+/-4 standard deviations as defined in the NELAC standards, and were accepted by the laboratory based on this allowance. No flags were applied for the marginal exceedences because the deviations are not expected to bias the sample results. Continuing Calibration Verification (CCV)Standards Percent differences (%Ds) for CCVs were not reviewed as part of the data evaluation process for data collected at the US Can—Welty Road site. However, the laboratory noted in the analytical reports that the CCVs analyzed before several samples for TPHd analysis were below the acceptance range. The samples were re-analyzed after a CCV within the acceptance criteria; however, the ending CCV for the second analyses was above the acceptance limit. The TPHd results were qualified E from samples SB-26-W-82-080815, SB-24B-W-39-080814, and SB-25- W-35-080818 for a potential bias. TPHd were not detected in samples QA-Tubing-R-080815, QA-Rinsate-Blank-R080815, and SB-27-W-36-080818. The results were not qualified because the second analysis confirmed the original analysis of these samples, and the results are not expected to be biased due to the CCV exceedence. Surrogates Surrogate recoveries were evaluated for all BTEX, PAH, and TPH methods. Three surrogates were used in the analysis of PAHs: nitrobenzene-d5, 2-fluorbiphenyl, and terphenyl-d14. PAH surrogate nitrobenzene-d5 is not associated with the target PAHs, and was not used to qualify sample results. The laboratory reported two surrogates for the TPHc analysis: chlorobenzene and orthoterphenyl. The recoveries for chlorobenzene were not evaluated because the compound does not elute within the target carbon range. Surrogate recoveries in all analyses were not E.1-3 �.:::: MMMFJ'11%�& From Science to Selatierrs