TABLE I
MINIMUM LINER DESIGN STANDARDS
Liner Material | Function | Minimum Field Thickness (Units as Specified) | Liner Density (Tests as Specified) | Remarks |
Geosynthetics | Primary or Secondary Liner | 30 mil | N/A | 1. A greater thickness may be required depending upon the recommendations of the manufacturer. HDPE liners shall be at least 60 MIL. |
Geosynthetics | Cap | 30 mil | N/A | 1. A greater thickness may be required depending upon the recommendations of the manufacturer. |
Natural & Remodeled Clay | Secondary Liner, Cap, Composite Component | 2 feet 2 feet 1 foot | [GREATER THAN EQUAL TO] 90%* [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 greater than or equal to 10.3. No coarse fragments greater than 3/4 inch in diameter. |
Sodium bentonite & Bentonite-like materials/soil mixtures | Secondary Liner, Cap, Composite Component | 2 feet 2 feet 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 | 1. Minimum of 3/4 pound of powdered or granular sodium bentonite per square foot. |
* Percentage of maximum when using Standard Proctor method of design (Pa. PTM No. 106, Method B).
Cross References
This table cited in 25 Pa. Code § 288.434 (relating to secondary liner); 25 Pa. Code § 288.436 (relating to primary liner); and 25 Pa. Code § 288.439 (relating to surface mined areas).
TABLE II
MINIMUM LINER DESIGN STANDARDS
Liner Material | Function | Minimum Field Thickness (Units as Specified) | Liner Density (Tests as Specified) | Remarks |
Geosynthetics | Liner, Cap | 30 mil | N/A | 1. A greater thickness may be required depending upon the recommendations of the manufacturer. HDPE liners shall be at least 60 MIL. |
Natural & Remolded Clay | Cap, Composite Component | 2 feet 1 foot | [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 greater than or equal to 10. 3. No coarse fragments greater than 3/4 inch in diameter. |
Sodium Bentonite and Bentonite-like materials | Cap, Composite Component | 2 feet 1 foot | [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 | 1. Minimum of 3/4 pound of powdered or granular sodium bentonite. |
* Percentage of maximum when using Standard Proctor method of design (Pa. PTM No. 106, Method B).
Pa. Code tit. 25, pt. I, subpt. D, art. IX, ch. 288, subch. F, ADDITIONAL OPERATING REQUIREMENTS-GENERAL, app A
This table cited in 25 Pa. Code § 288.234 (relating to final cover and grading); 25 Pa. Code § 288.535 (relating to liner); and 25 Pa. Code § 288.538 (relating to surface mined areas).