The provisions of 40 C.F.R. 141.74 are hereby adopted by reference in accordance with G.S. 150B‑21.6 including subsequent amendments and editions.  Copies are available for public inspection as set forth in Rule .0102 of this Subchapter.  These provisions are adopted with the following exceptions:

(1)           The residual disinfectant concentration of the water entering the distribution system shall be monitored continuously, and the lowest value shall be recorded each day, except that if there is a failure in the continuous monitoring equipment, grab sampling every four hours may be conducted in lieu of continuously monitoring, but for no more than five working days following the failure of the equipment.  Systems serving 3,300 or fewer persons may take grab samples in lieu of providing continuous monitoring on an ongoing basis at the frequency of every four hours that water is being treated.

(2)           In 40 C.F.R. 141.74, "0.2 mg/l" of residual disinfectant concentration shall be replaced with "0.2 mg/l measured as free chlorine when chlorine is the singular applied disinfectant and 1.0 mg/l measured as total chlorine when ammonia and chlorine are applied disinfectants."


History Note:        Authority G.S. 130A‑315; P.L. 93‑523; 40 C.F.R. 141.74;

Eff. January 1, 1991;

Amended Eff. April 1, 2014; October 1, 2009;

Pursuant to G.S. 150B-21.3A, rule is necessary without substantive public interest Eff. November 23, 2015.