SECTION 460:20-31-13. Subsidence control plan

(a)   Presubsidence survey. Each application must include:

(1)   A map of the permit and adjacent areas at a scale of 1:12,000, or larger if determined necessary by the Department, showing the location and type of structures and renewable resource lands that subsidence may materially damage or for which value or reasonably foreseeable use may be diminished by subsidence, and showing the location and type of drinking, domestic, and residential water supplies that could be contaminated, diminished, or interrupted by subsidence.

(2)   A narrative indicating whether subsidence, if it occurred, could cause material damage to or diminish the value or reasonably foreseeable use of such structures or renewable resource lands or could contaminate, diminish, or interrupt drinking, domestic, or residential water supplies.

(3)   A survey of the condition of all non-commercial buildings or occupied residential dwellings and structures related thereto, that may be materially damaged or for which the reasonably foreseeable use may be diminished by the subsidence, except for areas where there is no planned subsidence. Also, each application must include a survey of the quantity and quality of all drinking, domestic, and residential water, supplies within the permit area and adjacent area that could be contaminated, diminished, or interrupted by subsidence. If the applicant cannot make this survey because the owner will not allow access to the site, the applicant will notify the owner, in writing, of the effect the denial of access will have as described in 460:20-45-47(c)(4) of this Chapter. The applicant must pay for any technical assessment or engineering evaluation to determine the premining condition or value of such non-commercial buildings or occupied residential dwellings or structures related thereto and the quantity and quality of the drinking, domestic, or residential water supplies. The applicant must provide copies of the survey and any technical assessment or engineering evaluation to the property owner and Department.

(b)   Subsidence control plan. If the survey conducted under paragraph (a) of this section shows that no structures, or drinking, domestic, or residential water supplies, or renewable resource lands exist, or that no material damage or diminution in value or reasonably foreseeable use of such structures or lands, and no contamination, or interruption of such water supplies would occur as a result of mine subsidence, and if the Department agrees with this conclusion, no further information need be provided under this section. If the survey shows that structures, renewable resource lands, or water supplies exist and that subsidence could cause material damage or diminution in value or foreseeable use, or contamination, diminution, or interruption of protected water supplies, or if the Department determines that damage, diminution in value or foreseeable use, or contamination, diminution, or interruption could occur, that application shall include a subsidence control plan that contains the following information:

(1)   A description of the method of coal removal, such as longwall mining, room-and-pillar removal, hydraulic mining, or other extraction methods, including the size, sequence, and timing for the development of underground workings.

(2)   A map of underground workings which describes the location and extent of areas in which planned-subsidence mining methods will be used and which includes all areas where the measures described in (4), (5) and (b)(7) of this Section will be taken to prevent or minimize subsidence and subsidence related damage; and where appropriate, to correct subsidence-related material damage.

(3)   A description of the physical conditions, such as depth of cover, seam thickness, and lithology, which affect the likelihood or extent of subsidence and subsidence- related damage.

(4)   A description of monitoring, if any, needed to determine the commencement and degree of subsidence so that, when appropriate, other measures can be taken to prevent, reduce, or correct material damage in accordance with 460:20-45-47(c) of this Chapter.

(5)   Except for those areas where planned subsidence is projected to be used, a detailed description of the subsidence control measures that will be taken to prevent or minimize subsidence and subsidence-related damage, including, but not limited to:

(A)   Backstowing or backfilling of voids;

(B)   Leaving support pillars of coal;

(C)   Leaving areas in which no coal is removed, including by leaving coal in place; and

(D)   Taking measures on the surface to prevent material damage or lessening of the value or reasonably foreseeable use of the surface.

(6)   A description of the anticipated effects of planned subsidence, if any.

(7)   For those areas where planned subsidence is projected to be used, a description of methods to be employed to minimize damage from planned subsidence to non-commercial buildings and occupied residential dwellings and structures related thereto; or the written consent of the owner of the structure or facility that minimization measures not be taken; or unless the anticipated damage would constitute a threat to health or safety, a demonstration that the costs minimizing damage exceed the anticipated costs repair.

(8)   A description of the measures to be taken in accordance with 460:20-45-8 and 460:20-45-47(c) of this Chapter to replace adversely affected protected water supplies or to mitigate or remedy any subsidence-related material damage to the land and protected structures; and

(9)   Other information specified by the Department as necessary to demonstrate that the operation will be conducted in accordance with the performance standards of Section 460:20-45-47 of this Chapter for subsidence control.

[Source: Amended at 12 Ok Reg 117, eff 9-29-94 through 7-14-95 (emergency); Amended at 12 Ok Reg 3592, eff 10-12-95; Amended at 14 Ok Reg 3480, eff 8-11-97; Amended at 21 Ok Reg 2979, eff 7-26-04; Amended at 23 Ok Reg 3059, eff 7-27-06]