(A) The requirements of rules 3745-81-64 to 3745-81-69 of the Administrative Code are derived from national primary drinking water regulations. This rule establishes or extends treatment technique requirements in lieu of maximum contaminant levels for Cryptosporidium and are in addition to requirements for filtration and disinfection in rules 3745-81-71 to 3745-81-75 of the Administrative Code. These rule requirements apply to each public water system using a surface water source, in whole or in part. Wholesale systems must comply with the requirements of these rules based on the population of the largest system in the combined distribution system.
Consecutive systems are not exempt from the requirements of the LT2 rule. However, consecutive systems may receive water that a wholesale system has monitored and treated, if required, to comply with the LT2 rule. In this case, the consecutive system is not required to conduct additional monitoring or install additional treatment on that water under the requirements of the LT2 rule.
(B) Systems subject to this rule shall comply with the following requirements:
(1) Systems shall conduct an initial and a second round of source water monitoring for each plant that treats a surface water source, in whole or in part. This monitoring may include sampling for Cryptosporidium, E. coli, and turbidity as described in rule 3745-81-65 and paragraph (A) of rule 3745-81-66 of the Administrative Code, to determine what level, if any, of additional Cryptosporidium treatment that shall be provided.
(2) Systems that plan to make a significant change to their disinfection practice shall develop disinfection profiles and calculate disinfection benchmarks, as described in paragraph (E) of rule 3745-81-72 of the Administrative Code.
(3) Systems shall determine the appropriate Cryptosporidium treatment bin classification as described in paragraphs (A) to (D) of rule 3745-81-67 of theAdministrative Code and provide additional treatment for Cryptosporidium, if required, as described in paragraph (E) of rule 3745-81-67 of theAdministrative Code. Systems shall implement Cryptosporidium treatment in accordance with the schedule in paragraph (F) of rule 3745-81-67 of the Administrative Code.
(4) Systems required to provide additional treatment for Cryptosporidium shall implement microbial toolbox options that are designed and operated as described in rule 3745-81-68 of the Administrative Code.