1. (a) A pressurized potable water supply shall be provided for firefighting and use in the WWTP.
2. (b) No piping or other connections shall exist in any part of the WWTP or collection system that might cause the contamination of a potable water supply.
3. (c) The chemical quality of the water supply shall be checked for suitability for its intended uses such as heat exchangers and chlorinators.

4. (d) Potable water from a municipal or separate supply may be used directly at points above grade for the following hot and cold supplies with no additional backflow protection:

   1. (1) Lavatory sinks;
   2. (2) Toilets;
   3. (3) Showers;
   4. (4) Drinking fountains;
   5. (5) Laboratory sinks, if protected against back siphoning; and
   6. (6) Slop sinks, if protected against back siphoning.
5. (e) All potable water supply mains shall be protected against contamination with a reduced-pressure-zone backflow preventer that meets the requirements of Env-Dw 505, including local approval if required.
6. (f) Hot water for any unit cited in (d), above, shall not be taken directly from a boiler used for supplying hot water to a sludge heat exchanger, digester heating coils, or similar process.
7. (g) Where a public water supply is not available, a separate drilled well shall be provided as a potable water supply.
8. (h) Where a potable water supply will be used for any purpose other than those listed in (d), above, a backflow protection device that meets the requirements of Env-Dw 505, including local approval if required, shall be installed.
9. (i) Vacuum breakers shall be installed on the water supply to the laboratory.
10. (j) The number of backflow devices required shall be minimized by providing a separate, non-potable, in-plant water system using a single backflow protection device.
11. (k) A sign shall be permanently posted at each hose bib, sill cock, or other fixture on the non-potable water system indicating that the water is not safe for drinking.
12. (l) Where break tanks are used for backflow prevention, water shall discharge to the break tank through an air-gap at least 6 inches above the maximum flood line or the spill line of the tank, whichever is higher.
13. (m) Where a separate non-potable water supply will be provided, a backflow prevention device shall not be required.

14. (n) Hydrants for fire protection and hydrants for yard use shall:

    1. (1) Be clearly distinguished from one another with different paint colors; and
    2. (2) Have different-sized nozzles for hose connections.
15. (o) Locations of fire protection hydrants shall be approved by the appropriate local official.
16. (p) Hydrants fed by the potable water supply system shall be protected from cross-contamination as required by the owner of the water system.
17. (q) Toilets and showers shall be provided for the projected number of operators with separate toilets and showers for men and women.
18. (r) Slop sinks for general cleaning shall be provided.

Source. (See Revision Note at chapter heading for Env-Wq 700) #8590, eff 3-25-06; ss by #10693, eff 10-15-14; ss by #14258, eff 7-1-25, EXPIRES: 7-1-35