10A NCAC 42D .0249       MICROBIOLOGY METHODOLOGY

(a)  Minimum equipment requirements and methodology for microbiological analyses shall be in accordance with the methods adopted in 40 CFR 141.21(f) which is hereby incorporated by reference including any subsequent amendments and editions, except that Nutrient Agar plus MUG in 40 CFR 141.21(f)(6)(11) is not incorporated by reference.  A copy is available for inspection at the Division of Public Health, 1915 Mail Service Center, Raleigh, North Carolina 27699-1915.  Copies of 40 CFR 141-143 may be obtained by contacting the EPA Drinking Water Hotline at 800-426-4791 at no charge.

(b)  For total coliform analysis the laboratory shall maintain certification for one or more of the approved methods as specified in this Paragraph:

(1)           The Membrane Filter Procedure (MF) may be used for drinking water when the sample is free from interference (e.g. turbidity and particulates).  A laboratory must be approved for a second analytical procedure when MF is used.

(2)           The Multiple Tube Fermentation (MTF) procedure may be used for analyzing drinking water that contains particulates or other interfering substances and may be used as the back up or the sole approved method.

(3)           The ONPG-MUG Test and the Colisure Test may be used for analyzing drinking water that contains particulates.  These methods may be used as the back up or the sole approved method.

(c)  A laboratory shall maintain certification for one of the approved methods for fecal coliform analysis.

(d)  For all procedures in Paragraph (a) of this Rule the laboratory shall incubate inoculated culture within 30 minutes of inoculation.

 

History Note:        Authority G.S. 130A‑315;

Eff. December 1, 1991;

Amended Eff. January 1, 1996.