ARCHIVED REPORTS_WELL ABANDONMENT, SOIL, AND GROUNDWATER SUPPORTING DOCUMENTS

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Appendix E.1:Data Usability Summary Preservation and Holding Times All samples were received at the laboratory within the acceptance temperature criterion of 4+2 °C and were analyzed within specified holding times. Sample preservations, when required by the analysis,were less than the acceptance pH limit of 2. Reporting Limits Data reported for this sampling event were reported with the laboratory MDLs for soil samples and program-specified reporting limits for groundwater samples. The MDL represents the lowest concentration point where an analyte can be positively identified,but the quantitation is an estimate. The program reporting limits were used to report data below the applicable action levels. In some cases, the action levels for compounds may be below the analytical capabilities of the instruments used to determine the concentration of target compounds in environmental samples. The LOQ is the lowest concentration of an analyte in a sample that the laboratory can report with precision and accuracy. Analytes that were reported between the MDL and LOQ for this data set were qualified J as estimates. Reporting limits were raised for PAHs in some samples due to initial dilutions for extractions and/or before analysis for matrix interference. In addition, the reporting limits for acenaphthylene were raised in the following samples due to an interferent present in the sample near the retention time of the analyte: SB-21-S-60-080812, SB-23-S-36-080813, SB-26-S-51- 080814, SB-22-S-53-080813, SB-21-S-67-080812, SB-22-W-080813, SB-22-WD-080813, and SB-23-W-39-080814. The reporting limits for BTEX were also raised in some samples because the high-level soil method was performed due to the level of non-target compounds. Data with elevated reporting limits need to be evaluated carefully against applicable action levels to ensure that no data gaps exist. The PAHs benzo(b)fluoranthene and benzo(k)fluoranthene could not be resolved in samples SB-21-S-60-080812, SB-23-S-36-080813, SB-24-S-51-080814, SB-22-S-53-080813, SB-21-S- 67-080812, and SB-41-S-42-090304 due to matrix interferences. The result reported for benzo(b)fluoranthene represents the result for both isomers in these samples. The results were qualified E as estimated. Laboratory Fuel Notes for TPHd Analysis The laboratory noted that the observed hydrocarbon fuel patterns for TPHd analysis were atypical in the following groundwater samples: SB-18-W-080811, SB-19-W-080812, SB-22-W- 080813, SB-22-WD-080813, SB-24B-W-39-080814, SB-23-W-39-080814, SB-25-W-35- 080818, SB-29-W-36-081120, SB-37-W-35-081120, SB-42-W-090305, and SB-42-WD-090305. The laboratory noted that the observed chromatogram patterns for TPHd included hydrocarbons that eluted later than the diesel range. The laboratory noted that the chromatogram pattern did not resemble diesel in samples SB-26-W-82-080815, SB-37-W-35-081120, and QA_Screen-R- 080814 because the result was due to an individual peak eluting in the diesel-hydrocarbon range. Data were not qualified for the TPHd fuel pattern notes. Completeness Completeness is defined as the number of valid results (i.e., those not rejected) divided by the total number rejected. The evaluation of the data against the QC objectives concluded that the percentages of valid data for each method and matrix are 100 percent. E.1-7 From Science to Solutions