Section 289.438. Leachate collection system within protective cover

(a) The leachate collection system within the protective cover shall meet the following performance standards. The leachate collection system shall:

(1) Ensure that free flowing liquids and leachate will drain continuously from the protective cover to the leachate treatment system.

(2) Withstand chemical attack from leachate.

(3) Withstand anticipated loads, stresses and disturbances from overlying waste, waste cover materials and equipment operation.

(4) Function without clogging.

(5) Cover the bottom and sidewalls of the facility.

(b) Unless alternative design requirements to the performance standards in subsection (a) are approved as part of the permit under § 287.231 (relating to equivalency review procedure), the leachate collection system with the protective cover shall comply with the following design requirements.

(1) The leachate collection system shall include a perforated piping system which is capable of intercepting free flowing liquids and leachate within the protective cover and conveying them to a collection sump for storage, processing or disposal. The collection sump shall be of a sufficient size to transmit leachate that is generated and shall be capable of automatic and continuous functioning.

(2) The perforated piping system shall be sloped, sized and spaced to assure that free flowing liquids and leachate will drain continuously from the protective cover to the collection sump or point.

(3) The minimum diameter of the perforated pipes shall be 6 inches with a wall thickness of Schedule-80 or greater as specified by ASTM, or equivalent.

(4) The leachate collection system shall contain stones or aggregates.

(5) The pipes shall be installed primarily perpendicular to the flow and shall have a minimum postsettlement grade of at least 2%.

(6) The leachate collection system shall be cleaned and maintained as necessary.

(7) The leachate collection system shall have a minimum bottom slope of 2%.

(c) The Department may, in the permit, authorize the operator to delay activation of the leachate collection system until closure if the following are met:

(1) The impoundment is designed so that liquid covers waste during the active life of the facility.

(2) Wastes disposed at the impoundment are free draining.

(3) Solidification is solely dependent on gravity drainage.

(4) Test data or historical information, or both, from impoundments that received similar wastes show that the requirements of § 289.212(b) (relating to waste solidification) will be met 2 years after waste disposal ceases.

The provisions of this § 289.438 amended January 12, 2001, effective January 13, 2001, 31 Pa.B. 235. Immediately preceding text appears at serial pages (226765) to (226766).

Notation

Cross References

This section cited in 25 Pa. Code § 287.114 (relating to interim operational requirements for unpermitted processing or disposal facilities); 25 Pa. Code § 287.116 (relating to interim operational requirements); 25 Pa. Code § 289.212 (relating to waste solidification); 25 Pa. Code § 289.412 (relating to liner system and leachate control plan); 25 Pa. Code § 289.421 (relating to basic limitations); 25 Pa. Code § 289.431 (relating to scope and requirements); and 25 Pa. Code § 289.455 (relating to leachate collection and storage).