Okla. Admin. Code § 252:515-13-32

Current through Vol. 41, No. 19, June 17, 2024

Section 252:515-13-32 - Piping network

The leachate collection system shall be equipped with a piping network.

(1)Pipe material. Pipes shall be capable of withstanding the maximum overburden anticipated, and shall be constructed of at least six-inch diameter, schedule 80 PVC, HDPE-SDR of 11, or an equivalent approved by the DEQ. Piping with lesser strengths may be acceptable if supporting calculations are provided.

(2)Perforations. Pipes shall contain a minimum of two (2) rows of perforations no greater than 5/8 inch in diameter. Pipe perforations shall be drilled at an angle between 45° and 60° from the vertical and shall be spaced according to design loading and anticipated volume of leachate.

(3)Pipes. The piping system shall be designed and installed as follows:

(A)Orientation. Pipes shall be installed on top of the FML with perforations facing down.

(B)Pipe bends. The piping system shall have gradual sweep bends that are tied into one or more sumps designed to remove collected leachate from the system.

(C)Pipe slopes. Secondary collection lateral pipes shall maintain adequate slope after allowances for settlement. Primary centralized removal pipes shall maintain a slope of at least 0.5% after settlement.

(D)Spacing. Pipe spacing shall be based on the anticipated volume of leachate.

(E)Cleanouts. Cleanouts shall be placed so that all collection pipes can be accessed.

(i) Spacing of cleanouts shall be not exceed 1200 feet or available equipment, whichever is less. A larger spacing may be proposed if equipment is available that will accommodate the larger spacing.

(ii) Cleanouts shall be at least the same diameter as the collection pipe.

(iii) Penetrations of the liner shall be minimized.

(4)Backfill. Each pipe of the piping network shall be covered with a minimum of twelve inches (12") of material with a hydraulic conductivity of 1 x 10^-2 cm/sec or greater.

(5)Geotextile. Backfill around the piping network shall be covered with suitable geotextile fabric.

Okla. Admin. Code § 252:515-13-32

Added at 20 Ok Reg 1151, eff 6-1-03