40 CFR § 136.7 - Quality assurance and quality control.
The permittee/laboratory shall use suitable QA/QC procedures when conducting compliance analyses with any part 136 chemical method or an alternative method specified by the permitting authority. These QA/QC procedures are generally included in the analytical method or may be part of the methods compendium for approved Part 136 methods from a consensus organization. For example, Standard Methods contains QA/QC procedures in the Part 1000 section of the Standard Methods Compendium. The permittee/laboratory shall follow these QA/QC procedures, as described in the method or methods compendium. If the method lacks QA/QC procedures, the permittee/laboratory has the following options to comply with the QA/QC requirements:
(a) Refer to and follow the QA/QC published in the “equivalent” EPA method for that parameter that has such QA/QC procedures;
(b) Refer to the appropriate QA/QC section(s) of an approved part 136 method from a consensus organization compendium;
(1) Incorporate the following twelve quality control elements, where applicable, into the laboratory's documented standard operating procedure (SOP) for performing compliance analyses when using an approved part 136 method when the method lacks such QA/QC procedures. One or more of the twelve QC elements may not apply to a given method and may be omitted if a written rationale is provided indicating why the element(s) is/are inappropriate for a specific method.
(i) Demonstration of Capability (DOC);
(ii) Method Detection Limit (MDL);
(iii) Laboratory reagent blank (LRB), also referred to as method blank (MB);
(iv) Laboratory fortified blank (LFB), also referred to as a spiked blank, or laboratory control sample (LCS);
(v) Matrix spike (MS) and matrix spike duplicate (MSD), or laboratory fortified matrix (LFM) and LFM duplicate, may be used for suspected matrix interference problems to assess precision;
(vi) Internal standards (for GC/MS analyses), surrogate standards (for organic analysis) or tracers (for radiochemistry);
(vii) Calibration (initial and continuing), also referred to as initial calibration verification (ICV) and continuing calibration verification (CCV);
(viii) Control charts (or other trend analyses of quality control results);
(ix) Corrective action (root cause analysis);
(x) QC acceptance criteria;
(xi) Definitions of preparation and analytical batches that may drive QC frequencies; and
(xii) Minimum frequency for conducting all QC elements.