(a)

1. (1) Plants that treat domestic sewage for public health will be classified under this section.
2. (2) Package plants and sequencing batch reactors (SBRs) will be classified on the basis of each individual component (blower, activated sludge, clarification, disinfection, etc.).

(b) Each facility shall sum the total of rating points for each classification factor below, and based on the sum of all applicable rating points, the wastewater treatment facility shall be classified as:

1. (1) Class I – individual, single-dwelling houses that treat domestic sewage only;
2. (2) Class I – 01 – 25 rating points;
3. (3) Class II – 26 – 49 rating points;
4. (4) Class III – 50 – 74 rating points; and
5. (5) Class IV – 75 or greater rating points.

(c) Classification factor rating points.

1. (1)

   1. (A) Equivalent population served (one (1) point per each two thousand (2,000) population).
   2. (B) Equivalent population shall be calculated as flow in MGD x influent biochemical oxygen demand (BOD) x 8.34 divided by 0.17. (The maximum rating for this factor shall be forty (40).)

2. (2) Collection systems:

   1. (A) Lift station, one (1) or more – 5; and
   2. (B) Vacuum collection system – 0.

3. (3) Preliminary treatment:

   1. (A) Screens/bars – 2;
   2. (B) Comminutor – 3; and
   3. (C) Grit removal – 5.

4. (4) Clarification:

   1. (A) Primary settling and sludge removal – 4; and
   2. (B) Secondary settling and sludge removal – 6.

5. (5) Lagoon/pond/natural systems:

   1. (A) Stabilization/holding pond or ponds – 10; and
   2. (B) Aerated lagoons or lagoons/natural systems – 12.
6. (6) Fixed film systems (rotating biological contactor, trickling filter) – 12.

7. (7) Suspended growth systems:

   1. (A)

(i) Activated sludge.

1. (ii) Mechanical aeration/diffused air – 20;

   1. (B) Pure oxygen – 25; and
   2. (C) Neutralization – 5.

2. (8) Tertiary treatment:

   1. (A) Chemical treatment – 20;
   2. (B) Filtration – 15; and
   3. (C) Nutrient removal – 20.

3. (9) Disinfection:

   1. (A) Chlorine – 5;
   2. (B) Ozone – 7;
   3. (C) Ultraviolet light (UVL) – 5; and
   4. (D) Dechlorination – 5.

4. (10) Sludge treatment:

   1. (A) Thickening or dewatering – 6;
   2. (B) Aerobic digester – 6;
   3. (C) Anaerobic digester or digesters – 20;
   4. (D) Drying bed – 4;
   5. (E) Chemical conditioning – 10;
   6. (F) Vacuum/coil filter or filters/centrifuge/composting – 8;
   7. (G) Sludge heating – 5;
   8. (H) Dissolved air flotation (DAF) unit or units – 10; and
   9. (I) Sludge lagoon or lagoons – 6.

5. (11)

   1. (A) Sludge disposal.
   2. (B) Land application – 4.

6. (12) Land application of effluent with no direct discharge – 6.

   1. (d) Classification change.
7. (1) Should this revision of this part change the classification of a plant to a higher classification, the facility will be allowed two (2) years from the effective date of the revised part to allow operators to acquire the higher operator classification.
8. (2) If circumstances warrant and the Division of Environmental Quality receives a written request so justifying, a classification may be adjusted by the Director of the Division of Environmental Quality to serve the intent of the part as long as it ensures environmental protection.
9. (3) Permit modifications will be required to effect such a change.