Wisconsin Administrative Code
Department of Natural Resources
NR 100-199 - Environmental Protection General
Chapter NR 149 - Laboratory Accreditation
Subchapter IV - Accreditation Process
Section NR 149.19 - Requirements for certification in the drinking water matrix

(a) The minimum criteria and procedures for certification in the drinking water matrix are specified in the following documents:

(b) The department may not grant either interim or provisional certifications.

(c) A laboratory shall follow any additional criteria and procedures identified in this chapter applying to drinking water analyses.

(a) To receive and maintain certification to conduct analyses of inorganic contaminants, the laboratory shall achieve MDLs no greater than the MDLs specified in 40 CFR 141.23(a) (4) (i) and 40 CFR 141.89 (a) (1) (iii) for each accredited method.

Note: Links to 40 CFR Part 141 can be found on the Wisconsin department of natural resources laboratory accreditation program website.

(b) Each laboratory shall successfully analyze at least one PT sample annually according to criteria specified in 40 CFR 141.23(k) (3) (ii) or 40 CFR 141.89 (a) (1) (ii) (A) and (B) for each accredited method.

Note: Links to 40 CFR Part 141 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.

(a) To receive and maintain certification to conduct analyses of vinyl chloride, the laboratory shall achieve a MDL no greater than 0.0002 mg/L for each accredited method.

(b) Each laboratory shall successfully analyze at least one PT sample annually for each accredited method according to criteria specified in 40 CFR 141.24(f) (17) (ii) (B). Vinyl chloride is evaluated separately from the other regulated volatile organic compounds and certification for the regulated volatile organic compounds requires successful analysis of vinyl chloride in addition to requirements for the other regulated volatile organic compounds.

Note: Links to 40 CFR Part 141 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.

(a) To receive and maintain certification to conduct analyses of volatile organic compounds, excluding vinyl chloride, the laboratory shall achieve MDLs no greater than 0.0005 mg/L for all regulated volatile organic compounds for each accredited method.

(b) Each laboratory shall successfully analyze at least one PT sample annually for each accredited method according to criteria specified in 40 CFR 141.24(f) (17) (i) (B). Excluding vinyl chloride, a laboratory may be certified for all volatile organic compounds if the laboratory successfully analyzes at least 80% of the regulated volatile organic compounds.

Note: Some PT sample providers include the trihalomethanes in the sample for regulated volatile organic compounds. Trihalomethanes are not considered part of the "80%" rule. To be accredited for the regulated volatile organic compounds, vinyl chloride and 16 of the remaining 20 regulated volatile organic compounds are to pass in each PT sample.

Note: Links to 40 CFR Part 141 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.

(a) To receive and maintain certification to conduct analyses of synthetic organic contaminants, the laboratory shall achieve MDLs no greater than the MDLs specified in 40 CFR 141.24(h) (18) for each accredited method.

Note: Links to 40 CFR Part 141 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.

(b) Each laboratory shall successfully analyze at least one PT sample annually according to criteria specified in 40 CFR 141.24(h) (19) (i) (A) and (B).

Note: Links to 40 CFR Part 141 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.

(a) To receive and maintain certification to conduct analyses of disinfection by-products, the laboratory shall meet the requirements specified in 40 CFR 141.131(b) (2) (iv) for each accredited method. To receive certification to conduct analyses of trihalomethanes, the laboratory shall achieve MDLs no greater than 0.0005 mg/L for each regulated analyte for each accredited method.

Note: Links to 40 CFR Part 141 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.

(b) For the haloacetic acid and trihalomethane PT samples, laboratories shall pass 80%, or 4 of the analytes present in each PT sample.

(a) Fluoride analysis required under s. NR 809.74.

(b) Analysis for free chlorine residual and total chlorine residual required under s. NR 809.74.

(c) Analysis for pH required under s. NR 809.548.

(d) Analysis for turbidity required under s. NR 809.113.