25 Pa. Code § 86.175 : ENVIRONMENTAL PROTECTION — DEPARTMENT OF ENVIRONMENTAL PROTECTION — Protection Of Natural Resources — LAND RESOURCES — SURFACE AND UNDERGROUND COAL MINING: GENERAL — BONDING AND INSURANCE REQUIREMENTS —RELEASE OF BONDS — Schedule for release of bond

(a) The Department will not release any portion of the liability under bonds applicable to a permit area or designated phase of a permit area until it finds that the permittee has complied with §§ 86.171, 86.172 and 86.174 (relating to procedures for seeking release of bond; criteria for release of bond; and standards for release of bonds).
(b) The amount of bonds applicable to a permit area or designated phase of a permit area which may be released shall be calculated on the following basis:
(1) Release of an amount not to exceed 60% of the total bond amount on the permit area or designated phase of a permit area upon completion and approval by the Department of Stage 1 reclamation.
(2) Release of an additional amount of bond on the permit area or designated phase of a permit area upon completion and approval by the Department of Stage 2 reclamation but retaining an amount of bond coverage sufficient to cover the cost of reestablishing vegetation and reconstructing drainage structures if completed by a third party and for the period specified for permit liability in § 86.151 (relating to period of liability).
(3) Release of the remaining portion of the total bond on the permit area or designated phase of a permit area after standards of Stage 3 reclamation have been attained.

25 Pa. Code § 86.175