A. Each supplier using surface water or GWUDISW shall provide multibarrier treatment that meets the requirements of this Chapter and reliably ensures at least:
- 1. a total of 99.9 percent (3 Log) reduction of Giardia cysts through treatment processes including filtration and disinfection;
- 2. a total of 99.99 percent (4 Log) reduction of viruses through treatment processes including filtration and disinfection;
- 3. a total of 99 percent (2 Log) removal of Cryptosporidium oocysts through treatment processes including filtration;
- 4. the total reductions to be required by the DHH may be higher and are subject to the source water concentration of Giardia lamblia, viruses, and Cryptosporidium;
- 5. the residual disinfectant concentration in the water delivered to the distribution system is not less than 0.5 mg/l free chlorine or 0.5 mg/l total chlorine for more than 4 hours in any 24 hour period; and
- 6. the residual disinfectant concentration is not less than 0.5 mg/l free chlorine or 0.5 mg/l total chlorine in more than 5.0 percent of the samples collected each month from the distribution system for any two consecutive months.
- B. Suppliers meeting the requirements of §§1115 and 1119 shall be deemed to be in compliance with the minimum reduction and removal requirements specified in §1113.A of this Chapter.
- C. Section 1117 of this Chapter presents requirements for non-filtering systems. All suppliers which use surface water as a source shall provide filtration. On a case by case basis, systems using GWUDISW may not be required to filter.
Authority Note
AUTHORITY NOTE: Promulgated in accordance with R.S. 40:4(A)(8) and R.S. 40:5(2)(3)(5)(6)(17)(20).
Historical Note
HISTORICAL NOTE: Promulgated by the Department of Health and Hospitals, Office of Public Health, LR 28:1340 (June 2002), amended LR 28:2518 (December 2002), LR 35:1241 (July 2009), LR 42:411 (March 2016).