1. A. Grading of water treatment plants. This subsection does not apply to a facility that distributes water but does not treat water or to a facility that distributes water and disinfects by chlorine gas or hypochlorite only to maintain disinfection levels in the distribution system. The Department shall grade a water treatment plant according to the sum of the points it the Department assigns for each plant characteristic.

   1. 1. The Department shall assign points for the purpose of grading a water treatment plant as follows:

      Plant Characteristics	Points
      Population	1 per 5,000
      Maximum Design Capacity	1 per Millions of Gallons per Day up to 10
      Groundwater Source	3

      Surface or Groundwater Under the
      Direct Influence of Surface Water

      Source	5
      Carbon Dioxide	2
      pH Adjustment	3
      Packed Tower Aeration	6
      Air Stripping	6
      Stability or Corrosion Control	3
      Taste and Odor	8
      Iron/Manganese Removal	8
      Ion Exchange Softening	10
      Chemical Precipitation Softening	15
      Coagulant Addition	6
      Flocculation	4
      Sedimentation	4
      Upflow Clarification	2
      Fluoridation	5
      Activated Alumina	6
      Blending	5
      Residual Waste Stream	5
      Control Systems Technology	2
      Biologically Active Filter	20
      Granular Media Filter	15
      Pressure Filter	15
      Gravity Sand Filter	10
      Membrane Filtration	15
      Chlorine Gas	6
      Hypochlorite Liquid	2
      Hypochlorite Solid	2
      Chloramine	9
      Chlorine Dioxide	9
      Ozone	12
      Ultraviolet	3

   2. 2. The Department shall assign a grade by the total number of points assigned to the facility, as follows:

      Grade	Point Range
      Grade 1	1 to 25
      Grade 2	26 to 50
      Grade 3	51 to 70
      Grade 4	More than 70

2. B. Grading of water distribution systems. The Department shall grade a distribution system according to the sum of the points the Department assigns for each system characteristic.

   1. 1. The Department shall assign points for the purpose of grading a distribution system as follows:

      System Characteristics	Points
      Population	1 per 5,000
      Maximum Design Capacity	1 per Millions of Gallons per Day up to 10
      Pressure Zones	5
      Booster Stations	5
      Storage Tanks	3
      Blending	5
      Fire Protection Systems/Testable Backflow Prevention Assemblies*	5
      Cathodic Protection	3
      Control System Technologies	2
      Chlorine Gas	6
      Hypochlorite Liquid	2
      Hypochlorite Solid	2
      Chloramine	9
      Chlorine Dioxide	9

      *The presence of one or both of these devices earns five points for the facility.

   2. 2. No points are added for Grade 1 small systems that:

      1. a. Only distribute groundwater;
      2. b. Serve fewer than 501 persons;
      3. c. Have no disinfection or disinfect by chlorine gas or hypochlorite only; and
      4. d. Do not store water or store water only in storage tanks.

   3. 3. The Department shall assign a grade by the total number of points assigned to the facility, as follows:

      Grade	Point Range
      Grade 1	0
      Grade 2	1 to 20
      Grade 3	21 to 35
      Grade 4	More than 35

Historical Note

Former Section R9-20-520 repealed, new Section R9-20-520 adopted effective November 1, 1979 (Supp. 79-6). Former Section R9-20-520 amended, renumbered as Section R9-20-515, then renumbered as Section R18-4-115 effective October 23, 1987 (Supp. 87-4). R18-5-115 recodified from R18-4-115 (Supp. 95-2). Amended by final rulemaking at 7 A.A.R. 1171, effective February 16, 2001 (Supp. 01-1). Amended by final rulemaking at 7 A.A.R. 5079, effective October 16, 2001 (Supp. 01-4). Amended by final rulemaking at 11 A.A.R. 998, effective April 2, 2005 (Supp. 05-1).