Authority: IC 13-14-8; IC 13-15-1-2; IC 13-15-2-1; IC 13-18-3-1; IC 13-18-4-1

Affected: IC 13-11-2; IC 13-13-5-1; IC 13-18-2; IC 22-12

Sec. 14. (a) A hydropneumatic storage tank shall conform with the following:

1. (1) The requirements of IC 22-12 and 680 IAC.
2. (2) Shall not be buried except when in accordance with subdivisions (3) and (4).
3. (3) A tank shall be protected from freezing and flooding.

4. (4) Provide housing as follows:

   1. (A) A hydropneumatic storage tank with an air-water diaphragm separator shall be within the housing.
   2. (B) Hydropneumatic storage tanks without an air-water separator shall have all nontank mechanical parts, including valves, piping, and components, within the housing.

5. (5) Be equipped to provide the following:

   1. (A) The ability to isolate the tank from the rest of the public water system.
   2. (B) A drain.

   3. (C) Control equipment consisting of the following:

      1. (i) A pressure gauge.
      2. (ii) Pressure relief valve.

      3. (iii) Air addition as follows:

         1. (AA) Manual air addition may suffice for a hydropneumatic storage tank with an air-water diaphragm separator.
         2. (BB) Equipment for automatic air addition shall be required for all other hydropneumatic storage tanks.
      4. (iv) Start and stop controls for the pumps.

(b) The usable capacity of a hydropneumatic storage tank must meet one (1) of the following:

1. (1) Be a minimum of three (3) times the installed rated capacity, in gallons per minute, of the primary pump, or pumps if more than one (1) pump is used to meet peak system demand, at an operating pressure of at least thirty-five (35) pounds per square inch.
2. (2) Be based on the manufacturer's pump specifications.
3. (3) Meet an alternative criteria approved by the commissioner.

(c) Unless required by IC 22-12 or 680 IAC to be certified by ASME, a hydropneumatic storage tank shall be certified by American National Standards Institute (ANSI), The American Society of Mechanical Engineers (ASME), National Sanitation Foundation (NSF International), or Underwriter's Laboratories, Inc. (UL). The applicant must submit information showing that the tank used is properly certified.

(d) Hydropneumatic tank storage of water shall not be designated for fire protection purposes.

(e) A hydropneumatic tank shall not be used in a community public water system when more than four hundred (400) persons are served.

(f) If more than one (1) hydropneumatic tank is used in series, each tank must:

1. (1) be able to be hydraulically isolated from the others using valves or similar devices;
2. (2) have sampling taps for performing water quality sampling; and
3. (3) be operated and maintained to ensure adequate water turnover.

(Water Pollution Control Division; 327 IAC 8-3.4-14; filed Jun 17, 1999, 1:50 p.m.: 22 IR 3373; readopted filed Jan 10, 2001, 3:23 p.m.: 24 IR 1518; filed Apr 24, 2006, 3:00 p.m.: 29 IR 2966; readopted filed Nov 21, 2007, 1:16 p.m.: 20071219-IR-327070553BFA; readopted filed Jul 29, 2013, 9:21 a.m.: 20130828-IR-327130176BFA; readopted filed Jun 14, 2019, 1:59 p.m.: 20190710-IR-327190246BFA; readopted filed Oct 18, 2024, 1:57 p.m.: 20241113-IR-327230810RFA)