Current through Register Vol. 60, No. 12, December 1, 2021
(1) Design and
equipment must emphasize ease of maintenance, longevity, and reliability of
components and must be proven suitable by operational experience, test, or
analysis acceptable to the department.
(2) Easy means of electrical and plumbing
disconnect must be provided. All apparatus must be constructed and installed to
facilitate ease of service without having to alter any other
(3) Component materials
must be durable and corrosion-resistant such as Type 316 stainless steel,
suitable plastics, or 85-5-5 -5 bronze.
Pumps, Siphons, Controls, and Alarms. All
pumps, siphons, controls and related apparatus must be field tested under
working conditions and found to operate and perform satisfactorily. Electrical
components used in onsite systems must comply with applicable requirements of
the State of Oregon Electrical Code and the standards in this section.
(a) Motors must be continuous-duty with
(b) Pumps must
have durable impellers of bronze, cast iron, or other materials approved by the
(c) Submersible pumps
must be provided with an easy, readily accessible means of electrical and
plumbing disconnect and a noncorrosive lifting device as a means of removal for
(d) Except where
specifically authorized in writing by the agent, the pump or siphon must be
placed within a corrosion-resistant screen or vault with a filtering device
that extends into or above the tank's service access manhole. The screen or
filtering device must have at least 12 square feet of surface area, with
1/8-inch openings. In lieu of the screen, the agent may allow other methods
with equal or better performance in preventing the passage of suspended solids
to the pump or siphon.
must be automatically controlled by float switches with a minimum rating of 12
amps at 115 volts A.C. or by a department-approved, equally reliable switching
mechanism. Except as otherwise required in this division, the switches must be
installed so that no more than 20% of the projected daily sewage flow is
discharged each cycle. The pump "off" level must be set to maintain the liquid
level above the top of the pump or to the designer and pump manufacturer's
(f) An audible and
visual high water level alarm with manual silence switch must be located in or
near the building served by the pump. Only the audible alarm may be
user-cancelable. The switching mechanism within a dosing tank or chamber
controlling the high water level alarm must be located so that at time of
activation the tank has a remaining volume equal to 1/3 or more of the system's
design flow, as measured below the invert of the inlet, for effluent storage.
The alarm and pump must be on separate circuits. Commercial applications using
duplex pumps are not subject to the 1/3 storage reserve requirement.
(g) When a system has more than one pump, the
department may require the pumps to be wired into the electrical control panel
to function alternately after each pumping cycle. If either pump should fail,
the other pump will continue to function while the high water level alarm
activates. A cycle counter must be installed in the electrical control panel
for each pump.
(h) All pump
installations must be designed with adequate sludge storage volume below the
effluent intake level of the pump.
(i) All commercial systems with a design flow
greater than 600 gallons must be constructed in duplex (two or more alternating
pumps) unless otherwise authorized in writing by the department. Controls must
be provided such that an alarm will signal when one1 of the pumps
(j) All pumps serving
commercial systems must be operated through a pre-manufactured electrical
control panel. A means of monitoring pump performance through the use of
elapsed-time meters and cycle counters is required.
(k) Where multiple pumps are operated in
series, an electrical control panel must be installed to prevent the operation
of a pump or pumps preceding a station that experiences a high level alarm
Siphons. Dosing siphons used in onsite systems must comply with the following
(a) The siphon must be
constructed of corrosion-resistant materials.
(b) The siphon must be installed within a
compatible tank in accordance with the siphon manufacturer's
(c) The siphon
manufacturer must provide installation and maintenance instructions to the
(d) The installation must
include a device that tracks the operation of the siphon by measuring cycle
events and records them by means of an event counter mounted within the
dwelling or structure served.
Or. Admin. R.
DEQ 10-1981, f. & ef.
3-20-81; DEQ 23-1981(Temp), f. & ef. 9-2-81; DEQ 5-1982, f. & ef.
3-9-82; DEQ 15-1986, f. & ef. 8-6-86; DEQ 27-1994, f. 11-15-94, cert. ef.
4-1-95; DEQ 12-1997, f. & cert. ef. 6-19-97; DEQ 11-2004, f. 12-22-04,
cert. ef. 3-1-05
Stat. Auth.: ORS 454.625 & 468.020
Stats. Implemented: ORS