15A NCAC 18C .1002 DISINFECTION OF WELLS
(a) After water supply wells have been cleaned of foreign substances, including sediment, grease and oil, the wells shall be disinfected by the addition of chlorine solution in concentrations sufficient to produce a minimum chlorine residual of 100 milligrams per liter (or ppm) in the entire water column within the well casing.
(b) The chlorine solution shall remain in the well for a period of 24 hours. The well shall then be pumped until the water is free of chlorine.
(c) A representative sample or samples of the water shall be collected and analyzed by a certified laboratory. If bacteriological tests indicate that the water is free of bacteriological contamination, the well may be placed in service.
History Note: Authority G.S. 130A‑315; 130A‑317; P.L. 93‑523;
Eff. January 1, 1977;
Readopted Eff. December 5, 1977;
Amended Eff. July 1, 1994.