1. (a) The subbase shall meet the following performance standards. The subbase shall:

   1. (1) Bear the weight of the liner system, waste, waste cover material and equipment operating on the facility without causing or allowing a failure of the liner system.
   2. (2) Accommodate potential settlement without damage to the liner system.
   3. (3) Be a barrier to the transmission of liquids.
   4. (4) Cover the bottom and sidewalls of the facility.

2. (b) Unless alternative design requirements to meet the performance standards in subsection (a) are approved as part of the permit under § 287.231 (relating to equivalency review procedure), the subbase shall meet the following design requirements. The subbase shall:

   1. (1) Consist of an upper 6 inches that is:

      1. (i) Compacted to a standard proctor density of at least 95%.
      2. (ii) No more permeable than 1.0 x 10^-5 cm/sec., based on laboratory and field testing.
      3. (iii) Hard, uniform, smooth and free of debris, rock fragments, plant materials and other foreign material.
   2. (2) Have a minimum bearing capacity of 4,500 pounds per square foot plus the total applied load in pounds per square foot.
   3. (3) Have a slope of at least 2% and no more than 25%.

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 § 289.512 (relating to liner system and leachate control plan); 25 Pa. Code § 289.521 (relating to limitations); 25 Pa. Code § 289.531 (relating to scope and requirements); and 25 Pa. Code § 299.144 (relating to operating requirements).