2023-10-03_REVISION - M1977344 (23)

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Quality Assurance Project Plan Red Creek Quarry Monitoring Program Section 5: Data Generation and Acquisition 5-3 Duplicates can be “replicates” (samples taken one immediately after the other, separated only by the actual time required to fill the sample container) or “splits” (subsamples drawn from the same initial volume of matrix). Relevant information will be recorded for the duplicates, just like the normal samples, in the field logbook, or field data sheet. Results from the field duplicate analysis will be included in the analytical report. 5.4.1.2 Equipment Blanks A blank is a sample of known matrix where the specific constituents requested for analysis are known to be absent or are present at concentrations less than the laboratory minimum limit of detection. Equipment blanks consist of blank sample matrix passed through or over non-dedicated sampling equipment to check the decontamination process between samples or sample sites. Equipment blanks may be collected when sampling equipment requiring decontamination (e.g., portable pumps and sampling manifolds) are carried from location to location. When collected, equipment blanks will also be submitted blind for analysis. 5.4.2 Laboratory QC Checks Laboratory QC checks are routinely performed as part of the analytical process and include internal checks for sample analysis activities. The frequency and type of QC samples are often analytical method dependent. The laboratory will report any variance from laboratory-assigned QC limits impacting the quality of sample results and may report details of internal laboratory QC if requested. Laboratory QC checks include the types of samples described below. 5.4.2.1 Method Blank Samples Method blank samples are used to assess laboratory contamination during all stages of sample preparation and analysis. Method blank samples will be prepared by the laboratory using reagent- grade water and are carried through the entire preparation and analytical process. The laboratory will analyze method blank samples at a frequency of one sample for each batch of up to 20 samples. 5.4.2.2 Laboratory Control Samples LCSs are multi-element matrix-specific standards with known analyte concentrations that are carried through the entire preparation and analytical process. LCSs are used to confirm the method control, accuracy, and precision of analyses for constituents that are analyzed on a total concentration or total recoverable concentration basis. The laboratory will analyze LCSs at a frequency of one sample for each batch of up to 20 samples. 5.4.2.3 Calibration Verification Samples Calibration verification samples are method standards with known concentrations used to assess analytical precision, accuracy, and stability of the instrument calibration. The laboratory will analyze calibration verification samples at a frequency of one sample for each batch of up to 10 samples and at the end of each workgroup. 5.4.2.4 MS Samples MS samples will be used to evaluate the effect of the sample matrix on the recovery of constituents. An MS sample is a split of a submitted sample that is fortified with a spiking solution containing known concentrations of the target analytes. The fortified split is carried through the entire digestion and analytical process. Analyses for the MS are compared to the non-spiked split, and recovery of the target analytes is calculated using the equation discussed in Section 4.1. Recovery data for MS