15A NCAC 18A .1725       WATER QUALITY

(a)  Prior to the initial use of a water supply, or after construction, maintenance, repairs, pump installation, or a report of a positive coliform sample, two consecutive bacteriological water samples taken at least 48 hours apart shall be collected by the Department and submitted to the Division of Laboratory Services of the Department of Environment, Health, and Natural Resources or another laboratory certified pursuant to 15A NCAC 20D for analysis.  Prior to collecting the sample, the water shall be tested and shall be negative for chlorine residual.  For the purposes of this Rule, confirmation means another positive sample result following the initial positive sample unless the last positive sample was preceded by two consecutive negative samples.

(b)  The water supply shall be deemed an imminent hazard under the following circumstances:

(1)           confirmation of the presence of fecal coliform bacteria.

(2)           determination by the Environmental Epidemiology Section of the Department that the presence of chemical constituents are present at levels that constitute an imminent hazard as defined in G.S. 130A-2(3).

(c)  The water supply shall be deemed unsafe for use under the following conditions:

(1)           confirmation of the presence of total coliform.

(2)           determination by the Environmental Epidemiology Section of the Department that the presence of chemical constituents are present at levels in violation of water quality standards found in 15A NCAC 18C .1500 and do not constitute an imminent hazard as defined in G.S. 130A-2(3).

(d)  After a positive sample has been followed by two consecutive negative samples collected at least 48 hours apart, follow-up samples shall be collected by the Department at least once each quarter, while the supply is in use, for one year.  There shall be no treatment procedures between the two consecutive negative samples.

 

History Note:        Authority G.S. 95‑225; 130A‑5(3); 130A‑230; 130A‑235; 130A‑236; 130A‑248; 130A‑257;

Eff. July 1, 1993;

Amended Eff. May 1, 1996.