R 325.10104 Definitions; D, E.

Rule 104. As used in these rules: (a) "Department" means the department of environmental quality or its authorized agent or representative. (b) "Deviation" means an exception to a department rule establishing minimum standards or requirements issued in writing or as a condition to a permit to a public water supply. (c) "Direct filtration" means a series of processes, including coagulation and filtration, but excluding sedimentation, resulting in substantial particulate removal. (d) "Director" means the director of environmental quality or his or her authorized agent or representative. (e) "Disinfectant contact time" (T in CT calculations) means the time in minutes that it takes for water to move from the point of disinfectant application or the previous point of disinfectant residual measurement to a point at or before the point where residual disinfectant concentration is measured. Disinfectant contact time in pipelines shall be calculated based on plug flow by dividing the internal volume of the pipe by the maximum hourly flow rate through that pipe. Disinfectant contact time within mixing basins and storage reservoirs shall be determined by tracer studies or an equivalent demonstration. (f) "Disinfection profile" means a summary of Giardia lamblia inactivation, and in certain cases virus inactivation, through the treatment plant. (g) "Distribution system" means a system that consists of the following components through which water is distributed and used or intended for use for drinking or household purposes: (i) Piping. (ii) Transmission or distribution mains. (iii) Pumps. (iv) Pumping stations. (v) Storage tanks. (vi) Controls. (vii) Associated appurtenances. (h) "Division" means the drinking water and radiological protection division of the department. (i) "Domestic or other non-distribution system plumbing problem" means a coliform contamination problem in a public water supply which has more than 1 service connection that is limited to the specific service connection from which the coliform positive sample was taken. (j) "Drawdown" means the difference between the static water level and the pumping water level in a well or, for a flowing artesian well, the difference between an established datum above ground and the pumping water level. (k) "Dual sample set" means a set of 2 samples collected at the same time and same location, with 1 sample analyzed for TTHM and the other sample analyzed for HAA5. Dual sample sets are collected for the purpose of conducting an IDSE under R 325.10719g and determining compliance with the TTHM and HAA5 MCLs under R 325.10610d and R 325.10719h to R 325.10719n. (l) "Effective corrosion inhibitor residual," for the purpose of lead and copper control, means a concentration that is sufficient to form a passivating film on the interior walls of a pipe. (m) "Emergency" means a situation in a public water supply that results in contamination, loss of pressure, lack of adequate supply of water, or other condition that poses an imminent hazard or danger to the public health. (n) "Enhanced coagulation" means the addition of sufficient coagulant for improved removal of disinfection byproduct precursors by conventional filtration treatment. (o) "Enhanced softening" means the improved removal of disinfection byproduct precursors by precipitative softening. (p) "EPA" means the United States environmental protection agency. (q) "Equivalent certificate" means a certificate which is issued to certain individuals. Individuals eligible for an equivalent certificate do not hold a current certificate but were issued certification before the effective date of the current rules. (r) "Established ground surface" means the intended or actual finished grade or elevation of the surface of the ground at the site of a water supply facility. (s) "Exemption" means an order, with appropriate conditions, time schedules, and compliance requirements, that is issued by the director to a public water supply permitting a public water supply to be in temporary noncompliance with a state drinking water standard, including a specified treatment technique.