(1) A dosing
septic tank may discharge effluent with a pump or dosing siphon from the clear
zone at the outlet end of the tank. These may be considered for installations
where the design flow does not exceed 600 gallons per day.
(a) The minimum total primary volume of the
tank must be 1,100 gallons for flows less than or equal to 450 gallons per day
and 1,500 gallons for flows greater than 450 and up to 600 gallons per
(b) The submerged volume at
the lowest operating liquid level must be at least 900 gallons. The remaining
capacity must be used to ensure optimum surge capacity and reserve storage
(c) Liquid levels must be
controlled in a manner that is consistent with pump dosing requirements
described in OAR chapter 340, divisions 071 and 073.;
(d) All apparatus must be constructed and
installed to facilitate ease of service without having to alter any other
manual described in OAR
must include additional information about siphon selection, installation of the
pump or siphon vault and screen, pump control and alarm levels, and the
watertight pass-through methods for electrical wiring and pipe.
Or. Admin. R.
DEQ 10-1981, f. & ef.
3-20-81; DEQ 27-1994, f. 11-15-94, cert. ef. 4-1-95; DEQ 11-2004, f. 12-22-04,
cert. ef. 3-1-05
Stat. Auth.: ORS 454.625 & 468.020
Stats. Implemented: ORS