Unless DEQ authorizes otherwise, large systems must comply with the following requirements.
- (1) Large system absorption facilities must be designed with distribution to the cells by means of pumps.
- (2) The absorption area must be divided into relatively equal units. Each unit may receive no more than 1300 gallons of effluent per day.
- (3) The replacement (repair) absorption area must be divided into relatively equal units, with a replacement absorption area unit located adjacent to an initial absorption area unit.
- (4) Effluent distribution must alternate between the absorption area units.
- (5) Each system must have at least two pumps.
- (6) The applicant must provide a written assessment of the impact of the proposed system on the quality of public waters and public health, prepared by a registered geologist, a certified engineering geologist qualified as a hydrogeologist, or a subordinate under the direction of either, except as specifically exempted in ORS 672.535.
- (7) The owners of all new and existing large systems must register those systems with DEQ as Underground Injection Control (UIC) systems under OAR chapter 340, division 044. Large systems receiving domestic waste are regulated under this division. Drainfields receiving nondomestic waste are also regulated under the UIC rules.
Statutory/Other Authority
ORS 454.625 & 468.020
Statutes/Other Implemented
ORS 454.615 & 468B.080
History
DEQ 29-2025, amend filed 10/01/2025, effective 01/01/2026
DEQ 15-2017, amend filed 10/31/2017, effective 11/01/2017
DEQ 14-2013, f. 12-20-13, cert. ef. 1-2-14
DEQ 11-2004, f. 12-22-04, cert. ef. 3-1-05
DEQ 12-1997, f. & cert. ef. 6-19-97
DEQ 27-1994, f. 11-15-94, cert. ef. 4-1-95
DEQ 8-1983, f. & ef. 5-25-83
DEQ 10-1981, f. & ef. 3-20-81