(1) Effluent Sewer Pipe: The effluent sewer
must be constructed with materials in conformance with state building sewer
standards. The effluent sewer pipe must have a minimum diameter of 3 inches.
When the septic tank is fitted with an effluent filter, the minimum nominal
diameter of piping may be reduced to 1-1/4 inches.
(2) Underdrain pipe. Underdrain pipe must
meet or exceed the requirements for Class 125 PVC pressure pipe as identified
inASTM Specification D 2241. The pipe and fittings must be marked
as required by ASTM Specification D 2241. The underdrain pipe must be
perforated in accordance with subsection (4)(d) of this rule or with 1/4-inch
slots cut halfway through the pipe at 4 inches center to center.
(3) Polyvinyl chloride (PVC) pressure
transport pipe, pressure manifolds, and pressure lateral pipe and fittings must
meet or exceed the current requirements for Class 160 PVC 1120 pressure pipe as
identified in ASTM Specification D 2241. The pipe and fittings must be marked
as required by ASTM Specification D 2241. For pipe diameters of 1 inch or less,
the minimum pressure rating is 200 pounds per square inch (psi). For pipe
diameters greater than 1 inch, the minimum pressure rating is 160
Distribution and Header
Pipe and Fittings.
distribution pipe in 10 foot lengths and header pipe in lengths of 10 feet or
greater must meet the current ASTM Specification F 405. Pipe and fittings must
also pass a deflection test withstanding 350 pounds per foot without cracking
or collapsing using the method in ASTM 2412. Pipe used in absorption facilities
must be heavy duty. Markings must meet requirements in ASTM F 405.
(b) Polyvinyl chloride (PVC) distribution and
header pipe and fittings must meet the most currentASTM Specification D
2729. Pipe and fittings must pass a deflection test withstanding 350
pounds per foot without cracking or collapsing using the method found in ASTM
2412. Markings must meet requirements in ASTM Specification D 2729.
(c) Polyethylene smooth wall distribution and
header pipe in 10-foot length and fittings must meet the most current ASTM
Specification F 810. Pipe and fittings must also pass a deflection test of 350
pounds per foot without cracking or collapsing by using the method found in
ASTM 2412. Markings shall meet the requirements inASTM Specification F
(d) The three types of plastic pipe described
above must have two rows of holes spaced 120 degrees apart and 60 degrees on
either side of a center line. For distribution pipe, a line of contrasting
color must be provided on the outside of the pipe along the line furthest away
and parallel to the two rows of perforations. Durable ink markings must cover
at least 50% of the pipe. Markings may consist of a solid line, letters, or a
combination of the two. Intervals between markings must not exceed 12 inches.
The holes of each row may not be more than 5 inches on center and must have a
minimum diameter of 1/2 inch.
Or. Admin. R.
DEQ 10-1981, f. & ef.
3-20-81; DEQ 5-1982, f. & ef. 3-9-82; DEQ 9-1982, f. & ef. 6-16-82; DEQ
15-1986, f. & ef. 8-6-86; DEQ 27-1994, f. 11-15-94, cert. ef. 4-1-95; DEQ
11-2004, f. 12-22-04, cert. ef. 3-1-05
Publications: Publications referenced are available from the
Stat. Auth.: ORS 454.625 & 468.020
Stats. Implemented: ORS