Wis. Admin. Code Department of Natural Resources NR 809.311

Current through October 28, 2024

Section NR 809.311 - Analytical requirements for microbiological contaminants

(1) ANALYTICAL METHODS. Analyses conducted to determine compliance with s. NR 809.31 shall be made in accordance with methods listed in Table F.

(2) SAMPLE VOLUME. The standard sample volume required for total coliform analysis, regardless of analytical method used, is 100 ml.

(3) SAMPLE COLLECTION PRESERVATION AND HOLDING TIME.

(a) Sample collection for microbiological contaminants under s. NR 809.30 shall be conducted using the sample preservation, containers and maximum holding time procedures specified in par. (b).

(b) Sample preservation requirements and holding times for microbiological samples are specified in subds. 1. and 2. In all cases, samples shall be analyzed as soon after collection as possible.

1. Total Coliform and E. coli samples are not required to be preserved by cooling to 10° C, however it is encouraged during transit. Sodium thiosulfate shall be added to the sample container prior to adding water containing chlorine and the holding time shall be 30 hours.

2. Heterotrophs may be either held at room temperature with a holding time of 6 hours or preserved by cooling to 4° C with a holding time of 24 hours.

(4) LABORATORY CERTIFICATION. Analyses under this section shall only be conducted by laboratories that have received certification under ch. ATCP 77 or approval by EPA.

(5) PRESENCE OR ABSENCE. Water suppliers need only determine the presence or absence of total coliforms; a determination of total coliform density is not required.

Note: The coliform density may, however, be helpful in selecting a remedial option.

(6) REQUIRED METHODS. Samples collected to determine compliance with s. NR 809.30(1) shall be analyzed by enzyme substrate test methods.

(7) OTHER METHODS. The department may approve, on a case-by-case basis, other methods for use in determining compliance with s. NR 809.30(1) if they have been approved by EPA.

(8) SAMPLE INTEGRITY. If chlorine odor is present in a drinking water sample the laboratory shall test the sample for the presence of chlorine. If chlorine is detected in the sample, the laboratory shall reject the sample for analysis, based on the improper preservation. The water supplier shall submit a new sample for analysis to replace the rejected sample. - See PDF for table

¹Standard Methods for the Examination of Water and Wastewater, 20th edition (1998). Available from American Public Health Association, 800 I Street, NW., Washington, DC 20001-3710.

²Standard Methods for the Examination of Water and Wastewater, 21st edition (2005). Available from American Public Health Association, 800 I Street, NW., Washington, DC 20001-3710.

³Standard Methods for the Examination of Water and Wastewater, 22nd edition (2012). Available from American Public Health Association, 800 I Street NW., Washington, DC 20001-3710.

⁴ Standard Methods Online are available at http://www.standardmethods.org. The year in which each method was approved by the Standard Methods Committee is designated by the last two digits in the method number. The methods listed are the only online versions that may be used.

⁵ Lactose broth, as commercially available, may be used in lieu of lauryl tryptose broth, if the system conducts at least 25 parallel tests between lactose broth and lauryl tryptose broth using the water normally tested, and if the findings from this comparison demonstrate that the false-positive rate and false-negative rate for total coliforms, using lactose broth, is less than 10 percent.

⁶ A multiple tube enumerative format, as described in Standard Methods for the Examination of Water and Wastewater 9221, is approved for this method for use in presence-absence determination under this regulation.

⁷ EPA Method 1604, EPA 821-R-02-024 "EPA Method 1604: Total Coliforms and Escherichia coli in Water by Membrane Filtration Using a Simultaneous Detection Technique (MI Medium)," September 2002, http://www.epa.gov/nerlcwww/1604sp02.pdf.

⁸ Multiple-tube and multi-well enumerative formats for this method are approved for use in presence-absence determination under this regulation.

⁹ Colisure® results may be read after an incubation time of 24 hours.

¹⁰ E*Colite®-"Charm E*Colite T Presence/Absence Test for Detection and Identification of Coliform Bacteria and Escherichia coli in Drinking Water," January 9, 1998.

¹¹ Readycult®-"Readycult ® Coliforms 100 Presence/Absence Test for Detection and Identification of Coliform Bacteria and Escherichia coli in Finished Waters," January 2007, Version 1.1. Available from EMD Millipore (division of Merck KGaA, Darmstadt, Germany), 290 Concord Road, Billerica, MA 01821.

¹² modified Colitag®, ATP D05-0035-" Modified Colitag T Test Method for the Simultaneous Detection of E. coli and other Total Coliforms in Water," August 28, 2009. Available at http://www.nemi.gov or from CPI, International, 580 Skylane Boulevard, Santa Rosa, CA 95403.

Wis. Admin. Code Department of Natural Resources NR 809.311

CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10.

Amended by, CR 15-049: am. (3) (b) 1., (6), (7), r. and recr. Table F Register March 2016 No. 723, eff.4/1/2016