Okla. Admin. Code § 252:641-12-1

Current through Vol. 42, No. 7, December 16, 2024

Section 252:641-12-1 - General provisions

(a)Primary settling. Prior to being conveyed to a dispersal field, all sewage must first pass through a septic tank or trash tank for primary settling.

(b)Delivery method. All sewage shall be conveyed to the dispersal field through solid pipe, which shall meet the specifications listed in Appendix C.

(c)Surface water. Surface water shall be diverted around or away from the dispersal field.

(d)Types of dispersal fields. The following are the allowed types of dispersal fields:

(1) Conventional subsurface absorption fields;

(2) Shallow extended subsurface absorption fields;

(3) Evapotranspiration/absorption (ET/A) fields;

(4) Low pressure dosing fields;

(5) Drip irrigation fields; and

(6) Spray irrigation fields.

(e)Specifications for storage media. Storage media shall meet the following requirements:

(1)Storage capacity. All storage media shall provide a storage capacity of:

(A) at least five (5) gallons per linear foot in the bottom ten inches (10") of a twenty-four inch-wide trench in a conventional subsurface absorption field or ET/A field; or

(B) at least three and one-half (3-1/2) gallons per linear foot in the bottom six inches (6") of a twenty-four-inch-wide trench in a shallow extended subsurface absorption field.

(2)Media size. Storage media shall be one-half to two and one-half inches (1/2" to 2-1/2") in diameter with no more than ten percent (10%) by weight passing through a one-half inch (1/2") screen.

(3)Media with specific gravity of less than 1.0 If the specific gravity of the storage media is less than 1.0, it shall be bundled with a netting sleeve.

(4)Resistant to degradation. The storage media shall be non-degradable by septic tank effluent.

(5)Hardness of natural media. Natural materials (e.g., rock, etc.) used as storage media shall have a Mohs hardness of at least 3.0.

(6)Deflection rate for manufactured media. Manufactured materials (e.g., glass, plastic, polystyrene, etc.) used as storage media shall have a deflection rate of ten percent (10%) or less when subjected to a minimum of ten (10) psi for ninety-six (96) hours (ASTM D2221-01).

(f)Dispersal Systems. Systems utilized for the treatment of sewage shall meet the following requirements:

(1)Perforated pipe with storage media. When perforated pipe and storage media are used to disperse and store effluent throughout the trenches, the following requirements shall apply:

(A)Perforated pipe. The perforated pipe shall:

(i) meet the minimum specifications listed in Appendix C;

(ii) extend the entire length of the trenches;

(iii) be installed in the center of the storage media and the trench.

(B)Storage Media. The storage media shall:

(i) be at least twenty-four inches (24") wide the entire length of the trench;

(ii) be level:

(I) in each trench; and

(II) across the dispersal field, unless installed in trenches of different elevations.

(2)Manufactured Media Systems. When manufactured media systems are used to disperse and store effluent throughout the trenches, the systems shall:

(A) have a minimum exterior width of twenty-two inches (22");

(B) have a permeable sidewall interface evenly distributed along the manufactured media system. If the manufactured media system does not meet the storage media minimum height requirement, then the trench shall be backfilled with storage media to the depth required for the dispersal field being installed;

(C) has been tested and certified by an ANSI accredited third party certifier as having a minimum load rating of American Association of State Highway and Transportation Officials H-10 with 12 inches of compacted soil cover over the top of the manufactured media system;

(D) be fabricated from durable, non-deteriorating materials;

(E) extend the entire length of the trenches;

(F) be level:

(i) in each trench; and

(ii) across the dispersal field, unless installed in trenches of different elevations.

Okla. Admin. Code § 252:641-12-1

Added at 25 Ok Reg 2318, eff 7-11-08

Amended by Oklahoma Register, Volume 38, Issue 10, February 1, 2021, eff. 1/4/2021

Amended by Oklahoma Register, Volume 38, Issue 24, September 1, 2021, eff. 9/15/2021

Amended by Oklahoma Register, Volume 41, Issue 23, August 15, 2024, eff. 9/15/2024