Current through Register Vol. 54, No.43, October 26, 2024
(a) The liner shall meet the following standards of performance: (1) The liner shall prevent the migration of leachate through the liner to the greatest degree that is technologically possible.(2) The effectiveness of the liner in preventing the migration of leachate may not be adversely affected by the physical or chemical characteristics of solid waste, solid waste constituents or leachate from the facility.(3) The liner shall be resistant to physical failure, chemical failure and other failure from the sources identified under § 277.161(d) (relating to liner system and leachate control plan).(b) Unless alternative design requirements to meet the performance standards in subsection (a) are approved as part of the permit under § 271.231 (relating to equivalency review procedure), the liner shall meet, at a minimum, the requirements of the table in subsection (f).(c) A liner shall: (1) Be no more permeable than 1 x 10-7 cm./sec. based on laboratory and field testing.(2) For synthetic liners, be installed according to manufacturer's specifications under the supervision of an authorized representative of the manufacturer. An approved assurance and quality control program shall be implemented in the field during the installation of the liner.(3) For remolded clay liners, be designed, installed and maintained according to a quality assurance and quality control plan approved by the Department.(4) Be inspected for uniformity, damage and imperfections during construction and installation.(d) Liners made of clay, bentonite and bentonite-like materials shall be constructed in compacted lifts not exceeding 6 inches in depth unless the operator submits data from a field demonstration validating the suitability of compacted lifts greater than 6 inches. A lift shall be scarified before placement of the next lift.(e) The operator may design, construct, operate and maintain a composite liner. (1) The liner shall have the following components:(i) An upper component made of a manufactured geosynthetic liner that meets the requirements of this section independently of the composite component.(ii) A lower component made of earthen material that meets the requirements of this section independently of the upper component.(2) The two components of the composite liner shall be designed, constructed and maintained to provide a compression connection, or direct continuous contact, between them.(f) A facility or a component thereof that is subject to this chapter may not have a liner based upon natural attenuation of leachate.TABLE I
MINIMUM LINER DESIGN STANDARDS
| Minimum Field |
| Liner Material | Function | Thickness (Units as Specified) | Liner Density (Tests as Specified) | Remarks |
| Geosynthetic | Liner, Cap | 30 mil 30 mil | NA | 1. A greater thickness may be required depending upon the recommendations of the manufacturer. 2. HDPE liners shall be at least 60 mil. |
| Natural & Remolded Clay | Liner, Cap Composite Component | 2 feet 1 foot 2 feet | [GREATER THAN EQUAL TO] 90%* [GREATER THAN EQUAL TO] 90%* | 1. Minimum of 30% fines by weight less than 0.074 mm particle size (#200 sieve). 2. Plasticity index. 3. No coarse fragments greater than 3/4 inch in diameter. |
| Sodium Bentonite & Bentonite- like materials | Liner, Cap Composite Component | 1 foot 1 foot 1 foot | [GREATER THAN EQUAL TO] 90%* [GREATER THAN EQUAL TO] 90%* [GREATER THAN EQUAL TO] 90%* | 1. Minimum of 8% powdered sodium bentonite or manufacturer's recommendations, whichever is greater. 2. No coarse fragments greater than 3/4 inch in diameter. 3. No organic matter. |
| Geosynthetic Clay liner (GCL) | Composite Component | N/A | N/A | Minimum of 3/4 pound of powdered or granular sodium bentonite per square foot. |
*Percentage is of maximum theoretical density when using Marshall method of design, and percentage of maximum when using Standard Proctor method of design (Pa. PTM No. 106, Method B).
This section cited in 25 Pa. Code § 277.161 (relating to liner system and leachate control plan); 25 Pa. Code § 277.164 (relating to application requirements for noncoal mine disposal); 25 Pa. Code § 277.233 (relating to final cover and grading); 25 Pa. Code § 277.251 (relating to scope and requirements); and 25 Pa. Code § 277.258 (relating to surface mined areas).