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Technical Memorandum on Soil Boring Investigation

Appendix B - Data Verification Report

1 - Introduction

This data validation report covers environmental aqueous and soil/sediment samples and associated field quality control (QC) samples collected from Camp Stanley Storage Activity (CSSA) Well 16 Site between February 21, 1995 and March 16, 1995.

Field QC samples collected were trip blanks, rinsate/equipment blanks, matrix spike/matrix spike duplicate (MS/MSDs), and field duplicates. The trip blanks were analyzed for volatile organics only. All other field quality control samples were analyzed for the same parameters as their associated samples.

Each data package submitted by Chemron Incorporated (Chemron) has been reviewed and validated following the guidelines described in the Quality Assurance Project Plan (QAPP), the National Functional Guidelines for Organic Data Review (OLM01.0), June 1991, and the Functional guidelines for Evaluating Inorganic Analyses, July 1988. Information included in the data packages included: sample results, laboratory QC results, a care narrative, and chain-of-custody forms. The information and decisions presented this report are based on the information supplied by the laboratories and guidelines in the QAPP and Functional Guidelines.

This report is organized by analysis group. Quality assurance (QA) items discussed for each analysis group include, as necessary: General, Deliverables, Holding Times, Instrument Performance Checks and Calibrations, Blanks, Surrogate Spikes, Matrix Spike Sample Recovery, and Field Duplicate Samples. 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. Data are qualified according to the definitions found on Table A.

2 - Metals

2.1   General

Metals analyses of soil and water samples collected at CSSA Well 16 Site were conducted by Chemron using SW-846 Method 3050 for sample preparation and Methods 6010 and 7420/7421 for sample analyses. Method 6010 was used to analyze for cadmium, calcium, chromium, copper, iron, lead, magnesium, manganese, nickel, and potassium. Methods 7420/7421 were used for low concentration lead analyses.

2.2   Deliverables

Each laboratory report package was checked for the presence of required laboratory information as specified in the QAPP and the laboratory subcontract. All deliverables were present.

2.3   Holding Times

The holding time for each of these metals analyses is six (6) months from sample collection to sample analysis. All analyses met holding time criteria.

2.4   Calibrations

Calibration criteria for ICP analyses require that the correlation coefficient for the single high-level standard be greater than 0.995. Percent recoveries for all calibration verifications must be between 90 and 110. According to a statement issued by the laboratory, all calibration results (verifications and blanks) met acceptance criteria.

2.5   Blanks

No target analytes should be present in any blank analyzed. Equipment blanks (ES), rinsate blanks (RB), and method blanks (MB) were analyzed for this phase of the project. Five EBs had target analytes detected above the instrument quantitation limit. Two EBs affected the corresponding samples. All the other samples contained greater than five (5) times the amount of the target analyte found in the respective blanks.

Copper in sample B28-SB3(GW) was less than five (5) times the amount found in its associated blank and was therefore qualified as non-detected (flagged "U"). Copper results in the following samples were less than five (5) times the amount found in the associated blank and were therefore qualified as non-detected (flagged "U"): B4-SB2 (23-25), B4-SB3 (33-34), B4-SB4 (11-16), B4-SB4 (27-29), B4-SB5 (9.5-11), B4-SB5 (26-27), and OX-SB1(3.5-5).

One RB (B4-SB5(EB)) was found to contain calcium at 2.9 mg/L, copper at 0.01 mg/L, and iron at 0.07 mg/L. The only associated sample to be affected was B4-SB5. Copper was qualified as non-detected (flagged "U").

All MBs were found to be free of target analytes above the instrument quantitation limit with the exception of the blanks listed below. The affected samples listed were found to contain less than five (5) times the amount in the corresponding MB, and have been qualified as non-detected (flagged "U").

2.6   Interferences

Occasionally, due to extremely high levels of one target analyte, false positive values in associated target analytes can be induced.

In the following samples, cadmium was qualified as non-detected (flagged "U") due to iron interferences: 43506, 43509, 43511, 43513, 43546 - 43550, 43588 - 43595, 43626 - 43630, 43158, 43160 - 43167, 43211 - 43216, 43257, 43258, 43260 - 43263, 43265 - 43267, 43324 - 43330, 43501 - 43504, 43723 - 43728, 43791 -43794, 43796 - 43798, 43800, 44189, 44190, 44194 - 44198, 44202, 44203, 44277, 44278, 44279, 43930 - 43932, 43935, 43936, 43937, 44117 - 44123, 44125, and 44126.

2.7   Matrix Spike Sample Recovery

Matrix spike/matrix spike duplicate (MS/MSD) sample %R criteria and RPD criteria are outlined below. All MS/MSD samples met spike recovery and RPD criteria.

2.8   Field Duplicate Samples

Field duplicate samples must agree within +/-50%. The following samples had field duplicate target analytes at an RPD greater than 50%. No data are qualified based on field duplicate criteria.

3 - Organics

3.1   General

Organics analyses of soil and water samples collected at CSSA Well 16 Site were conducted by Chemron using SW-846 Method 8260 for volatiles analyses and Method 8270 for semivolatile analyses. Method 5030 was used for volatile sample preparation and Method 3550 was used for semivolatile sample preparation.

3.2   Deliverables

Each laboratory report package was checked for the presence of required laboratory information as specified in the QAPP and the laboratory subcontract. All deliverables were present.

3.3   Holding Times

The holding time for Method 8260 is fourteen (14) days from sample collection to sample analysis. The holding time for Method 8270 is seven (7) days from sample collection to sample extraction and forty (40) days from sample extraction to sample analysis.

Twenty (20) samples were analyzed outside the holding time for Method 8260, due to either instrument malfunction or human error. These samples were analyzed at 15, 17, or 21 days from sample collection date. The following samples have been qualified as "J" if the analyte was detected and "UJ" if the analyte was not detected.

All semivolatile analyses met holding time criteria.

3.4   Instrument Performance Checks and Calibrations

Methods 8260 and 8270 require that certain ion abundance criteria be met when bromofluorobenzene and decafluorotriphenylphosphine, respectively, are analyzed. Methods 8260 and 8270 require five-point initial calibrations with continuing calibrations agreeing within +/-30% of the initial calibration response factor. Response factors must be greater than 0.050. According to a statement issued by the laboratory, all calibration results (initial and continuing) and performance checks met acceptance criteria.

3.5   Blanks

No target analytes should be present in any blank analyzed. Trip blanks (TB), equipment blanks (EB), rinsate blanks (RB), and method blanks (MB) were analyzed for this phase of the project.

For volatile analyses, the MB performed on 3/16/95 had acetone at 0.014 mg/L. Because no sample had acetone reported above the instrument quantitation limit, no further action was taken. All other MBs were free of target analytes above the instrument quantitation limit. All TBs, RBs, and EBs were free of target analytes above the instrument quantitation limit.

Fir semivolatile analyses, all the MBs and RBs were free of target analytes above the instrument quantitation limit. One EB (Chemron sample no. 44276, Parsons sample no. OX-SB4(EB)) had di-n-butylphthalate at 30 ug/L. However, none of the samples associated with this EB had results above the instrument reporting limit for this target analyte, so no action was required.

3.6   Surrogate Spikes

Laboratory surrogate spike recovery criteria for Methods 8260 and 8270 for soil and water samples follow:

For volatile analyses, two samples had low surrogate recoveries.

For each of these samples, all detected analytes were qualified as estimated (flagged "J") and all non-detected analytes were qualified as estimated undetected (flagged "UJ").

For semivolatile analyses, each sample is spiked with six surrogate compounds; three for the acid fraction (phenol-d6, 2-fluorophenol, 2,4,6-tribromophenol) and three for the base/neutral fraction (nitrobenzene-d5, 2-fluorobiphenyl, terphenyl-d14). Data are qualified if two or more surrogates within the same fraction are out of criteria. Should this situation occur, data are qualified according to the following rules.

Four samples were qualified according to the above criteria.

3.7   Matrix Spike Sample Recovery

Laboratory matrix spike and spike duplicate percent recovery (%R) criteria for Methods 8260 and 8270 for both water and soil analyses follow. Relative percent difference (RPD) criteria are also noted.

For the volatile analyses, one matrix spike (MS) %R for water on 3/15/95 was slightly above the acceptance criteria (129% vs. 125%) for the spiking compound chlorobenzene. This demonstrates a potential for a high bias for chlorobenzene results. However, chlorobenzene was not detected in any of the samples. Two matrix spike duplicates (MSDs) for soil had %R values that were slightly above the acceptance limit for 1,1-dichloroethene. On 3/8/95 the %R was 129% and on 3/10/95 the %R was 133% (vs. 128%). Again, this compound was not detected in any of the samples, so the potential for a high bias is irrelevant. No attempt was made to respike/reanalyze the MS or MSD samples. For the semivolatile analyses, all MS and MSD %Rs and RPDs met acceptance criteria.

3.8   Field Duplicate Samples

Field duplicate samples must agree with +/-50%. None of the volatile or semivolatile field duplicates had RPDs greater than 50%.

4 - Asbestos

One sample was analyses for asbestos (B4-SB1A (0-11)) by EPA Method 600/M4-82-020. The sample results were non-detected for each form of asbestos.

5 - Summary

5.1   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 the duplicate or replicate analyses. The laboratory's precision criteria for MS/MSD samples differ slightly from the criteria outlined in the QAPP. However, the laboratory criteria are determined by historical results and the effect on the data is negligible since the RPD criteria used by the laboratory is generally more stringent than that required by the QAPP. The laboratory limits are laid out in the appropriate sections. Precision criteria for field duplicate samples for this project is 50 percent.

5.2   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 %R of MS/MSDs and surrogate spikes. The laboratory's accuracy criteria for MS/MSD and surrogate spikes deviated from the criteria listed in the QAPP. However, the laboratory criteria are determined by historical resutls and the effect on the data is negligible since the %R criteria used by the laboratory is generally more stringent than that required by the QAPP. The laboratory limits are laid out in the appropriate sections.

5.3   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.

5.4   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 analyses are considered valid with the exception of those acid and base/neutral fractions of the semivolatile samples already discussed which were unusable due to surrogate recoveries which were out of criteria.

For sample B3-SB1 (29-30) (collected on 3/7/95) a change is noted on the chain-of-custody that requests a duplicate analysis as well as the regular sample analysis. Also, the client stated in a telephone conversation with the laboratory that she also wanted an MS/MSD analysis. However, neither the duplicate analysis nor the MS/MSD analysis were performed.

5.5   Comparability

Comparability is a qualitative measurement of the ability to compare one data set with another. Consistent and comparable analytical results were acquired through the use of an EPA approved analytical method and adherence to EPA recommended holding times, with the exception of the samples already noted which were performed outside of holding times.

Table A - Data Qualifier Definitions

The following definitions provide brief explanations of the national qualifiers assigned to results in the data review process. If the Regions choose to use additional qualifiers, a complete explanation of those qualifiers should accompany the data review.