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Page 8 of 24 <br />SOP NUMBER 28.0 An1111YUCai Data Validation <br />4.1.6.2.1 Surrogate Spike Compound Recovery <br />The surrogate recoveries obtained for each sample analysis for which surrogates were analyzed <br />will be compared to the acceptance range specified in the QUALITY ASSURANCE PLAN, <br />method, or that provided by the laboratory, as appropriate (per Section 4.1). Results for analytes <br />in the sample associated with surrogate recoveries outside the acceptance range will be qualified <br />as follows: <br />• If the surrogate recovery is greater than the upper acceptance limit for any surrogate (for <br />semivolatile organics by GC/MS, two or more surrogates in either fraction must be high), <br />suggesting a potential high bias in reported results, all positive results for associated analytes <br />in that sample are qualified as estimated ("J") whereas non-detect results are considered to be <br />acceptable for use without qualification. <br />• If the surrogate recovery is < the lower acceptance limit but >_ 10% (for semivolatile organics <br />by GC/MS, two or more surrogates in either fraction are out with at least one of them being <br />less than the lower limit but >_10%), suggesting a potential low bias in reported results, <br />positive and nondetect results for associated analytes in that sample are qualified as <br />estimated ("J" or "UJ" ). <br />• If any surrogate recovery is <10%, positive results for associated analytes in that sample are <br />qualified as estimated ("J") whereas associated non-detect results are qualified as unusable <br />("R"). <br />It is important to note that professional judgement may be utilized in assigning data qualification <br />especially for methods in which more that one surrogate compound is used or in which there <br />may have been multiple reasons for qualification on an individual result, or there may have been <br />multiple analyses of the same sample. The data review narrative will detail any instance in <br />which professional judgement was used. <br />A qualifier code of "SUR" will be assigned to all results qualified or rejected on the basis of <br />surrogate recoveries. An appropriate bias code will be assigned. <br />4.1.6.2.2 Internal Standards <br />The site wide QUALITY ASSURANCE PLAN and/or analytical method, as appropriate (per <br />Section 4.1) will be used to determine the QC acceptance criteria for internal standard area <br />counts for GC/MS organic analysis. Internal standard area counts are not a direct measure of the <br />accuracy of the analysis. Low internal standard area counts for sample analysis relative to those <br />observed in the associated continuing calibration analysis may be indicative of low extraction or <br />purging efficiency which decreases the analysis sensitivity (raises the detection limit). High <br />internal standard area counts may be indicative of co-eluting interferences at the retention time <br />of the internal standard in the sample, may be caused by a drift in detector sensitivity, or may be <br />caused by injection of a different amount of sample extract. Co-eluting interferences to the <br />internal standard may result in a low bias in reported results quantified by the given internal <br />standard. Injection of a larger volume of extract would result in increased sensitivity of the <br />analysis (lowered detection limit). <br />• If data validation indicates that internal standard area counts are below the lower acceptance <br />limit, then results reported as not-detected shall be qualified as estimated ("UJ") and results <br />Powertech <br />R Squared Inc <br />Rev 28-1 JAB Attachment A <br />4/23/2007