R 325.10106 Definitions; M to O.

Rule 106. As used in these rules: (a) "Maximum residual disinfectant level (MRDL)" means a level of a disinfectant added for water treatment that may not be exceeded at the consumer's tap without an unacceptable possibility of adverse health effects. (b) "Maximum TTHM potential" means the maximum concentration of total trihalomethanes produced in a given water containing a disinfectant residual after 7 days at a temperature of 25 degrees Centigrade or above. (c) "MCL" means the maximum permissible level of a contaminant in water that is delivered to any user of a public water supply. (d) "MDL" means method detection limit for analytical work done to determine compliance with the act. (e) "Medium-size water system" or "medium-size water supply," for the purpose of lead and copper control, means a public water supply that serves more than 3,300 persons and fewer than or equal to 50,000 persons. (f) "Membrane filtration" means a pressure or vacuum driven separation process in which particulate matter larger than 1 micrometer is rejected by an engineered barrier, primarily through a size-exclusion mechanism, and which has a measurable removal efficiency of a target organism that can be verified through the application of a direct integrity test. This definition includes the common membrane technologies of microfiltration, ultrafiltration, nanofiltration, and reverse osmosis. (g) "Monitoring requirement" means a schedule, frequency, and location for the sampling and analysis of water that is required by the provisions of part 7 of these rules to determine whether a public water supply is in compliance with the state drinking water standards. (h) "Near the first service connection" means at 1 of the 20% of all service connections in the entire system that are nearest the water supply treatment facility, as measured by water transport time within the distribution system. (i) "Noncommunity supply" or "noncommunity water supply" or "noncommunity water system" means a public water supply that is not a community supply, but that has not fewer than 15 service connections or that serves not fewer than 25 individuals on an average daily basis for not less than 60 days per year. (j) "Nontransient noncommunity water supply" or "nontransient noncommunity water system" or "NTNC" means a noncommunity public water supply that serves not fewer than 25 of the same individuals on an average daily basis over 6 months per year. This definition includes water supplies in places of employment, schools, and day-care centers. (k) "NTU" means nephelometric turbidity unit. (l) "One hundred-year drought elevation" means the minimum projected water surface elevation that would occur at a location once in a period of 100 years. (m) "One hundred-year flood elevation" means the maximum projected water surface elevation that would occur at a location once in a period of 100 years. (n) "Operating shift" means that period of time during which operator decisions that affect public health are necessary for proper operation of the waterworks system. (o) "Operator" means an individual who operates a waterworks system or a portion of a waterworks system. (p) "Operator in charge" means a certified operator who is designated by the owner of a public water supply as the responsible individual in overall charge of a waterworks system, or portion of a waterworks system, who makes decisions regarding the daily operational activities of the system that will directly impact the quality or quantity of drinking water. (q) "Optimal corrosion control treatment," for the purpose of lead and copper control, means the corrosion control treatment that minimizes the lead and copper concentrations at users' taps while ensuring that the treatment does not cause the public water supply to be in violation of any national primary drinking water regulations.