ARCHIVED REPORTS_2010 ANNUAL REPORT

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QUALITY CONTROL ELEMENTS NARRATIVE TestAmerica conducts a quality assurance/quality control (QA/QC) program designed to provide scientifically valid and legally defensible data. Toward this end, several types of quality control indicators are incorporated into the QA/QC program, which is described in detail in QA Policy,QA-003. These indicators are introduced into the sample testing process to provide a mechanism for the assessment of the analytical data. Program or agency specific requirements take precedence over the requirements listed in this narrative. OC BATCH Environmental samples are taken through the testing process in groups called QUALITY CONTROL BATCHES (QC batches). A QC batch contains up to twenty environmental samples of a similar matrix(water,soil)that are processed using the same reagents and standards. TestAmerica North Canton requires that each environmental sample be associated with a QC batch. Several quality control samples are included in each QC batch and are processed identically to the twenty environmental samples. For SW846/RCRA methods,QC samples include a METHOD BLANK(MB),a LABORATORY CONTROL SAMPLE(LCS)and, where appropriate, a MATRIX SPIKE/MATRIX SPIKE DUPLICATE (MS/MSD) pair or a MATRIX SPIKE/SAMPLE DUPLICATE (MS/DU) pair. If there is insufficient sample to perform an MS/MSD or an MS/DU, then a LABORATORY CONTROL SAMPLE DUPLICATE(LCSD)is included in the QC batch. For 600 series/CWA methods,QC samples include a METHOD BLANK(MB),a LABORATORY CONTROL SAMPLE(LCS)and, where appropriate, a MATRIX SPIKE (MS). An MS is prepared and analyzed at a 10% frequency for GC Methods and at a 5% frequency for GC/MS methods. LABORATORY CONTROL SAMPLE The Laboratory Control Sample is a QC sample that is created by adding known concentrations of a full or partial set of target analytes to a matrix similar to that of the environmental samples in the QC batch. Multi peak responders may not be included in the target spike list due to co-elution. The LCS analyte recovery results are used to monitor the analytical process and provide evidence that the laboratory is performing the method within acceptable guidelines. All control analytes indicated by a bold type in the LCS must meet acceptance criteria. Failure to meet the established recovery guidelines requires the repreparation and reanalysis of all samples in the QC batch. Comparison of only the failed parameters from the first batch are evaluated. The only exception to the rework requirement is that if the LCS recoveries are biased high and the associated sample is ND(non-detected)for the parameter(s) of interest,the batch is acceptable. At times,a Laboratory Control Sample Duplicate(LCSD)is also included in the QC batch. An LCSD is a QC sample that is created and handled identically to the LCS. Analyte recovery data from the LCSD is assessed in the same way as that of the LCS. The LCSD recoveries, together with the LCS recoveries, are used to determine the reproducibility (precision) of the analytical system. Precision data are expressed as relative percent differences (RPDs). If the RPD fails for an LCS/LCSD and yet the recoveries are within acceptance criteria,the batch is still acceptable. METHOD BLANK The Method Blank is a QC sample consisting of all the reagents used in analyzing the environmental samples contained in the QC batch.Method Blank results are used to determine if interference or contamination in the analytical system could lead to the reporting of false positive data or elevated analyte concentrations. All target analytes must be below the reporting limits(RL)or the associated sample(s)must be ND except under the following circumstances: • Common organic contaminants may be present at concentrations up to 5 times the reporting limits. Common metals contaminants may be present at concentrations up to 2 times the reporting limit, or the reported blank concentration must be twenty fold less than the concentration reported in the associated environmental samples. (See common laboratory contaminants listed in the table.) Volatile GC or GUMS SemivolatileGUMS Metals ICP-MS Metals ICP Trace Methylene Chloride, Phthalate Esters Copper,Iron,Zinc, Copper,Iron,Zinc, Lead Acetone,2-Butanone Lead,Calcium, Magnesium,Potassium, Sodium,Barium, Chromium,Manganese North Canton Page 16 of 137 5