216 R.I. Code R. 216-RICR-50-05-5.7

Current through December 26, 2024

Section 216-RICR-50-05-5.7 - Classification of Water Supply Treatment Facilities and Water Supply Transmission and Distribution Facilities

A. Public water supply treatment and public water supply transmission and distribution facilities classified in any class may be classified in a higher class at the discretion of the Board, by reason of the existence of unusual operating conditions.

B. Classification of any water supply treatment or water supply distribution facility may be changed due to changes in any condition or circumstances under which the original classification was given. Due notice of any such change shall be given to the owner of the facility. Sufficient time shall be given to such system to obtain the required certifications.

C. Water supply treatment facilities and water supply transmission and distribution facilities shall be classified as very small water system, Class 1, Class 2, Class 3, or Class 4, with 4 being the largest and most complex, in accordance with the following classification system.

1. Water supply treatment facilities shall be classified according to the following point system:

a. Class VSST: less than ten (10) points

b. Class 1T: ten (10) to thirty (30) points

c. Class 2T: thirty-one (31) to fifty-five (55) points

d. Class 3T: fifty-six (56) to seventy-five (75) points

e. Class 4T: seventy-six (76) points and greater

2. Points shall be assigned to each plant according to the schedule in § 5.7(D) of this Part.

a. For purposes of certification, sources without treatment, such as pumping only, shall be considered to be a distribution system and not a treatment facility.

3. Water supply distribution and transmission facilities shall be classified according to the population served. The classifications are as follows:

a. Class VSSD: fewer than five hundred (500) persons served

b. Class 1D: five hundred (500) to one thousand five hundred (1,500) persons served

c. Class 2D: one thousand five hundred and one (1,501) to fifteen thousand (15,000) persons served

d. Class 3D: fifteen thousand and one (15,001) to forty thousand (40,000) persons served

e. Class 4D: forty thousand and one (40,001) or more persons served

D. Water Treatment Plant Classification

1. Notes on classifying treatment plants: Each unit process should have points assigned only once. (i.e., for a plant using oxidation, precipitation and filtration for iron removal, add ten (10) points for the iron removal only and nothing for filtration).

2. The points rating scale for water treatment plants is:

Item	Points
Size (two (2) to twenty (20) points total)
Maximum population served, peak day (one (1) to ten (10)) (Maximum of ten (10) points)	One (1) point per ten thousand (10,000) or part
Design flow, average day or peak month's average day, whichever is larger (one (1) to ten (10)) (Maximum of ten (10) points)	One (1) point per MGD or part
Water Supply Source (three (3) to eighteen (18) points)
Groundwater	Three (3)
Surface water	Five (5)
Average raw water quality (zero (0) to ten (10) points) (the key concept is the variation or change in the quality of the raw water source with point values ranging from zero (0) to ten (10))
Little or no variation	Zero (0)
Raw water quality (other than turbidity) varies enough to require treatment changes approximately ten percent (10%) of the time	Two (2)
Raw water quality (turbidity) varies severely enough to require pronounced and/or very frequent treatment changes	Five (5)
Raw water quality subject to periodic serious industrial waste pollution	Ten (10)
Aeration	Two (2)
Packed tower aeration	Six (6)
pH adjustment	Four (4)
Stability or corrosion control	Four (4)
Taste and odor control	Eight (8)
Color control	Four (4)
Iron or iron/manganese removal	Ten (10)
Ion exchange softening	Ten (10)
Chemical precipitation softening	Twenty (20)
Coagulant addition	Four (4)
Flocculation	Six (6)
Sedimentation	Five (5)
Upflow clarification	Fourteen (14)
Filtration	Ten (10)
Fluoridation	Five (5)
Disinfection (zero (0) to ten (10) points) (For disinfectants, such as ozone, chlorine dioxide or chloramines, assign five (5) points for chlorination or comparable and five (5) points for on-site generation of disinfectant)
No disinfection	Zero (0)
Chlorination or comparable	Five (5)
On-site generation of disinfectant	Five (5)
Gaseous chlorine	Five (5)
Special process (including reverse osmosis, electrodialysis)	Fifteen (15)
Sludge/backwash water disposal (zero (0) to five (5) points)
No disposal to raw water source to sewer or off watershed	Zero (0)
Any disposal to raw water source supernatant discharge to reservoir	Two (2)
Any disposal to plant raw water	Five (5)
Laboratory control (zero (0) to twenty (20) points) (The key concept is to credit laboratory analyses done on-site by plant personnel with point values ranging from zero (0) to twenty (20) points)
Bacteriological/biological (zero (0) to ten (10) points)
Lab work done outside of plant	Zero (0)
Membrane filter procedures	Three (3)
Use of fermentation tubes or any dilution method; fecal coliform determination	Five (5)
Biological identification	Seven (7)
Viral studies of similarly complex work done on site	Ten (10)
Chemical/physical (zero (0) to ten (10) points)
Lab work done outside the plant	Zero (0)
Push button or colorimetric methods for simple tests such as chlorine residual, pH	Three (3)
Additional procedures such as titration jar tests, alkalinity, hardness	Five (5)
More advanced determinations such as numerous inorganics	Seven (7)
Highly sophisticated instrumentation such as atomic absorption and gas chromatography	Ten (10)

216 R.I. Code R. 216-RICR-50-05-5.7

Amended effective 10/7/2020