Chlorite is regulated under the _______ and has maximum contaminant level of ______.

Chlorite is regulated under the _______ and has maximum contaminant level of ______.

• A. Stage 1 Disinfectant and Disinfection Byproducts Rule, 1.0 mg/L
• B. Stage 1 Disinfectant and Disinfection Byproducts Rule, 0.5 mg/L
• C. Stage 2 Disinfectant and Disinfection Byproducts Rule, 0.5 mg/L
• D. Stage 2 Disinfectant and Disinfection Byproducts Rule, 1.0 mg/L

Answer: (A)

Chlorite is a disinfection byproduct that forms when chlorine dioxide is used to disinfect water, so it’s regulated under the Disinfectants and Disinfection Byproducts Rule. The limit set for chlorite is 1.0 mg/L, and this regulation is part of Stage 1 of the rule. Stage 2 focuses on reducing exposure to other byproducts like TTHMs and HAA5 and does not establish an alternate chlorite limit in the same way. Therefore, the pairing of Stage 1 with a 1.0 mg/L limit best matches how chlorite is regulated.

Chlorite is a disinfection byproduct that forms when chlorine dioxide is used to disinfect water, so it’s regulated under the Disinfectants and Disinfection Byproducts Rule. The limit set for chlorite is 1.0 mg/L, and this regulation is part of Stage 1 of the rule. Stage 2 focuses on reducing exposure to other byproducts like TTHMs and HAA5 and does not establish an alternate chlorite limit in the same way. Therefore, the pairing of Stage 1 with a 1.0 mg/L limit best matches how chlorite is regulated.