Section 410IAC6-8.3-64. Outlet filters

   (a) An outlet filter shall be installed in the septic tank of new on-site sewage systems and existing on-site sewage systems requiring a new septic tank.

  (b) For on-site sewage systems requiring repair, or soil absorption systems requiring replacement, the local health department may require an outlet filter. The outlet filter, if required by the local health department, must meet the requirements of this section.

  (c) Outlet filters shall be located in the outlet end of:

(1) a single septic tank when not used in series;

(2) the second compartment of two-compartment septic tanks;

(3) the last septic tank when two (2) or more tanks are used in series; or

(4) a secondary watertight structure located after the last septic tank prior to a dosing tank, distribution box, or secondary treatment unit.

  (d) An access opening of eighteen (18) inches in minimum dimension shall be:

(1) located over the outlet filter; and

(2) provided with a riser to grade that meets the minimum requirements of section 63(d) of this rule.

  (e) Outlet filters shall:

(1) conform to NSF/ANSI Standard 46-2010a, Evaluation of Components and Devices Used in Wastewater Treatment Systems, maintain a current product listing with an ANSI accredited third-party certifier, and bear a listing mark;

(2) be rated by the manufacturer for a daily flow equal to or greater than the liquid capacity of the septic tank;

(3) prevent the passage of solids larger than one-eighth (1/8) of an inch;

(4) have inlets and outlets of at least four (4) inches in diameter;

(5) function without a bypass of unfiltered sewage, sludge, or scum, during normal use;

(6) be made of a noncorrosive material designed for use in sewage applications;

(7) maintain structural integrity, not tearing or distorting so as to make it inoperable during normal operation, throughout the life of the device; and

(8) have removable outlet filter cartridges.

  (f) The outlet filter housing shall:

(1) connect to the outlet pipe or structure wall with noncorrosive fasteners;

(2) extend at least five (5) inches above the liquid level of the tank;

(3) be installed so the bottom of the filter inlet extends below the liquid level at least ten (10) inches, but not more than forty percent (40%) of the septic tank liquid depth;

(4) include a gas deflection device that remains in place when the filter cartridge is removed; and

(5) be solvent welded to a PVC Schedule 40 outlet pipe that meets the minimum requirements of section 67(a)(1) or 67(a)(2) of this rule, creating a watertight and mechanically sound joint.

  (g) A filter alarm may be installed in the septic tank to indicate when the outlet filter is in need of service.

  (h) An outlet filter with cartridge shall remain in service for the life of the septic tank.

  (i) Outlet filter manufacturers shall provide installation and maintenance instructions with each outlet filter. Outlet filters shall be:

(1) installed according to manufacturer's recommendations;

(2) located so they do not interfere with pumping and cleaning of the septic tank; and

(3) placed to allow accessibility for routine maintenance without entering the septic tank or outlet structure if separate from the septic tank.

  (j) Outlet filters shall be serviced according to the manufacturer's service recommendations, but no less frequently than each time the septic tank is cleaned, as follows:

(1) The outlet filter shall be:

(A) cleaned and washed so that the filter waste enters the septic tank; or

(B) exchanged with a clean filter.

(2) All contaminated effluent filters shall be treated as untreated sewage and handled properly during the cleaning or exchange process.

(Indiana State Department of Health; 410 IAC 6-8.3-64; filed Oct 19, 2012, 2:06 p.m.: 20121114-IR-410120156FRA; filed Apr 9, 2014, 9:51 a.m.: 20140507-IR-410130350FRA)