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Addendum to Remedial Investigation Report for B-20 Former Open Burn/Open Detonation Area
Appendix D - Data Validation Summary Report for Additional Soil Samples
Introduction
This data validation report covers environmental soil samples and associated field quality control (QC) samples collected from the B-20 former open burn/open detonation area at Camp Stanley Storage Activity (CSSA) from September 5 through 7, 1995, and analyzed for metals (total and leachate). Field QC samples collected along with the environmental samples were equipment blanks and matrix spike/matrix spike duplicates (MS/MSDs). All field quality control samples were analyzed for the same parameters as their associated environmental samples.
The data package submitted by Terra Laboratories, Ltd. (Terra) has been reviewed and validated following the guideline described in Section 6 of the Quality Assurance Project Plan (QAPP). Information included in the data packages included: sample results, laboratory QC results, a case narrative, and chain-of-custody forms. The information and decisions presented in this report are based on the information supplied by the laboratories and guidelines in the QAPP. Quality assurance (QA) items discussed include: General information, deliverables, holding times, calibrations, blanks, matrix spike sample recovery, inductively coupled plasma (ICP) interference check sample recovery, and laboratory check sample recovery. A summary on the overall acceptability of the data to meet the stated QAPP QA objectives is presented in the conclusion section of this report.
Metals
2.1 General
Metals analyses of soil (total, TCLP, SPLP) samples, and one aqueous equipment blank sample, collected at B-20 were conducted by Terra using atomic absorption (AA) and ICP spectroscopic methods. Terra reported results for Terra sample numbers 95005088 through 95005120.
2.2 Deliverables
Each laboratory report package was checked for the presence of required laboratory information as specified in Table 6.1 of the QAPP. All deliverables were present.
2.3 Holding Times
The holding time for metal analyses is twenty-eight (28) days from sample collection to sample analysis for mercury and six (6) months for all other metals. All analyses met holding time criteria.
2.4 Calibrations
Calibration criteria require that the correlation coefficient for the three (four for mercury standards in the initial AA calibration be greater than 0.995. ICP analyses require one high-level standard only. Percent recoveries for all calibration verifications must be between 90 and 110 (80-120 for mercury). All criteria were met for all samples.
2.5 Blanks
No target analytes should be present in any blank analyzed. All method blanks and equipment blanks were free of target analytes above the instrument quantitation limit for each target analyte.
2.6 Matrix Spike Sample Recovery
Matrix spike/matrix spike duplicate (MS/MSD) sample %R criteria is 75-125 %R and relative percent difference (RPD) of 20% for all analytes. All MS/MSD samples met spike recovery criteria with the exception of cadmium in sample B-20 SS54 (0.1-0.3), Terra sample number 95005106. The results for cadmium in this sample was qualified as estimated (flagged "J").
2.7 ICP Interference Check Sample Recovery
Percent recovery of all ICP interference check sample (ICS) results must be within 80 10 120 %R. All ICS samples met this criteria.
2.8 Laboratory Check Sample Recovery
Percent recovery of all laboratory control sample results for water analyses must be within 80 to 120 %R. All appropriate samples met this criteria.
3.1 Precision
Precision is an expression of the agreement between replicate results without assumption of any prior information on the true result. For this project, analytical precision is determined by the RPD of duplicate or replicate analyses. The RPD criteria used by the laboratory is generally more stringent than required by the QAPP so this has minimal or no impact on data quality. All samples met the laboratory's RPD criteria.
3.2 Accuracy
Accuracy is a measure of the nearness to the true value of a result or the mean of a set of results. For this project, analytical accuracy is expressed by the percent recovery (%R) of MS/MSDs and surrogate spikes. One sample failed to meet the laboratory's %R criteria. Laboratory control samples indicated that the instrument was performing properly at the time this noncompliant sample was analyzed so matrix effects are the suspected source of the failure.
3.3 Representativeness
Representativeness is the degree to which the sample data represents environmental conditions at the sampling point. The samples' representativeness was ensured by collecting appropriate field QC samples and using approved analytical methods. The equipment blank did not contain target analytes.
3.4 Completeness
Completeness is a measure of the amount of usable data resulting from a data collection activity. For this project completeness is determined by comparing the number of tests requested with the number of valid samples reported by the laboratory. All requested analyses were analyzed and reported. All analyses are considered valid.
3.5 Comparability
Comparability is a qualitative measurement of the ability to compare one data set with another. Consistent and comparable analytical results were acquired through use of an EPA-approved analytical method and adherence to EPA recommended holding times.