Wisconsin Administrative Code
Department of Natural Resources
NR 100-199 - Environmental Protection General
Chapter NR 149 - Laboratory Accreditation
Subchapter VII - Quality Systems
Section NR 149.41 - Method selection

(1) The laboratory shall use methods for environmental testing required by covered programs under this chapter and that are suitable for the matrix, type of analyte, expected level of analyte, regulatory limit, and potential interferences in the samples to be tested.

Note: Sources, including the following as updated, likely contain methods that are acceptable for testing under this chapter: The EPA, the department, Standard Methods for the Examination of Water and Wastewater, Test Methods for Evaluating Solid Waste, Physical/Chemical Methods - SW-846, American Society for Testing and Materials, and the U.S. Geological Survey Agency.

(2) When methods are not specified by covered programs under this chapter or specified in permits issued by the department, the laboratory shall consult with the department to select a method that meets the requirements in sub. (1).

(3) When using methods associated with the methods compendium document, "Test Methods for Evaluating Solid Waste," the laboratory shall comply with the minimum requirements of the methods as written and state which options are being implemented when options exist.

Note: The documents above can be found on the Wisconsin department of natural resources laboratory accreditation program website and are available for inspection at the offices of the department and the legislative reference bureau.

(4) The department will assess the scientific validity of method modifications to determine if the modification is within the scope of a method.