North Dakota Administrative Code
Title 33.1 - Department of Environmental Quality
Article 33.1-17 - Public Water Supply Systems
Chapter 33.1-17-01 - Public Water Supply Systems in North Dakota
Section 33.1-17-01-06 - Maximum contaminant levels, action levels, and treatment technique requirements, and maximum residual disinfectant levels

1. Inorganic chemicals. The maximum contaminant levels, action levels, and treatment technique requirements for inorganic chemical contaminants excluding disinfection byproducts shall be as prescribed by the department and set forth under title 40 Code of Federal Regulations, part 141 subpart G.

At the discretion of the department, nitrate levels not to exceed twenty milligrams per liter may be allowed in a noncommunity water system if the supplier of water demonstrates to the satisfaction of the department that:

2. Organic chemicals. The maximum contaminant levels and treatment technique requirements for organic chemical contaminants excluding disinfection byproducts and disinfection byproduct precursors shall be as prescribed by the department and set forth under title 40 Code of Federal Regulations part 141, subpart G.

3. Filtration and disinfection treatment.

4. Radioactivity. The maximum contaminant levels for radioactivity are as follows:

5. Microbiological. The treatment technique triggers, treatment technique violations, E.coli maximum contaminant level violations, and monitoring violations are as follows:

6. Disinfectants. The maximum residual disinfectant levels for disinfectants are as follows:

The department identifies the following as the best technology, treatment techniques, or other means available for achieving compliance with the maximum residual disinfectant levels: control of treatment processes to reduce disinfectant demand and control of disinfection treatment processes to reduce disinfectant levels.

7. Disinfection byproducts. The maximum contaminant levels for total trihalomethanes, haloacetic acids five, bromate, and chlorite are as follows:

The department identifies the following as the best technology, treatment techniques, or other means available for achieving compliance with the maximum contaminant level for total trihalomethanes and the maximum contaminant levels for haloacetic acids five, bromate, and chlorite: for total trihalomethanes and haloacetic acids five, enhanced coagulation, enhanced softening, or granular activated carbon ten with chlorine as the primary and residual disinfectant; for bromate, control of the ozone treatment process to reduce production of bromate; and for chlorite, control of treatment processes to reduce disinfectant demand and control of disinfection treatment processes to reduce disinfectant levels. All best available technology and compliance shall be prescribed by the department and set forth under title 40 Code of Federal Regulations part 141.64.

8. Disinfection byproduct precursors. The department hereby identifies enhanced coagulation and enhanced softening as treatment techniques to control the level of disinfection byproduct precursors in drinking water treatment and distribution systems. The treatment techniques apply only to subpart H community and nontransient noncommunity water systems that use conventional treatment. Such systems shall be deemed to be in compliance with the treatment techniques if the requirements set forth under title 40 Code of Federal Regulations part 141, subpart L, are met.

9. Confirmation sampling. The department may require confirmation samples and average confirmation sample results with initial sample results to determine compliance. At the discretion of the department, sample results due to obvious monitoring errors may be deleted prior to determining compliance.