Authority: IC 14-34-2-1

Affected: IC 14-34

Sec. 49. (a) Each application shall include a general plan and a detailed design plan for each proposed siltation structure, water impoundment, and coal processing waste dam, embankment, or refuse pile within the proposed permit area. The information required shall be provided as follows:

1. (1) Each general plan shall do the following:

   1. (A) Be prepared by, or under the direction of, and certified by a qualified registered professional engineer or by a professional geologist either of whom shall be experienced in the design and construction of impoundments.
   2. (B) Contain a description, map, and cross section of the structure and its location.
   3. (C) Contain preliminary hydrologic and geologic information required to assess the hydrologic impact of the structure.
   4. (D) Contain a survey describing the potential effect on the structure from subsidence of the subsurface strata resulting from past underground mining operations if underground mining has occurred.
   5. (E) Contain a certification statement that includes a schedule setting forth the dates when any detailed design plans for structures that are not submitted with the general plan will be submitted to the director. The director shall have approved, in writing, the detailed design plan for a structure before construction of the structure begins.

2. (2) Each detailed design plan for a structure shall do the following:

   1. (A) Be prepared by, or under the direction of, and certified by a qualified registered professional engineer, with assistance from experts in related fields, such as geology, land surveying, and landscape architecture.
   2. (B) Include any geotechnical investigation, design, and construction requirements for the structure.
   3. (C) Describe the operation and maintenance requirements for each structure.
   4. (D) Describe the timetable and plans to remove each structure, if appropriate.
   5. (E) Identify those structures that meet or exceed the size and other criteria of 30 CFR 77.216(a), and include a copy of the plans for design and construction that has been approved by the Mine Safety and Health Administration for those identified structures.

(b) Siltation structures, whether temporary or permanent, shall be designed in compliance with the requirements of 312 IAC 25-6-17. Any siltation structure or earthen structure that will remain on the proposed permit area as a permanent water impoundment shall also be designed to comply with the requirements of 312 IAC 25-6-20.

(c) Permanent and temporary impoundments shall be designed to comply with the requirements of 312 IAC 25-6-20 and the requirements of the Mine Safety and Health Administration at 30 CFR 77.216-1 and 30 CFR 77.216-2.

(d) Refuse piles shall be designed to comply with 312 IAC 25-6-36 through 312 IAC 25-6-39.

(e) Coal processing waste dams and embankments shall be designed to comply with the requirements of 312 IAC 25-6-34, 312 IAC 25-6-36, and 312 IAC 25-6-43 through 312 IAC 25-6-45. Each plan shall also comply with the requirements of the Mine Safety and Health Administration, 30 CFR 77.216-1 and 30 CFR 77.216-2, and shall contain the results of a geotechnical investigation of the proposed dam or embankment foundation area to determine the structural competence of the foundation that will support the proposed dam or embankment structure and the impounded material. The geotechnical investigation shall be planned and supervised by an engineer or engineering geologist according to the following:

1. (1) The number, location, and depth of boring and test pits shall be determined using current, prudent engineering practice for the size of the dam or embankment, quantity of material to be impounded, and subsurface conditions.
2. (2) The character of the overburden and bedrock, the proposed abutment sites, and any adverse geotechnical conditions that may affect the particular dam, embankment, or reservoir site shall be considered.
3. (3) All springs, seepage, and ground water flow observed or anticipated during wet periods in the area of the proposed dam or embankment shall be identified on each plan.
4. (4) Consideration shall be given to the possibility of mudflows, rock-debris falls, or other landslides into the dam, embankment, or impounded material.

(f) If the structure meets the Class B or C criteria for dams in TR-60 or meets the size and other criteria of 30 CFR 77.216(a), each plan under subsections (b), (c), and (e) shall include the following:

1. (1) A stability analysis of the structure that shall include, but not be limited to:

   1. (A) Strength parameters.
   2. (B) Pore pressures.
   3. (C) Long term seepage conditions.
2. (2) A description of each engineering design assumption and calculation with a discussion of each alternative considered in selecting the specific design parameters and construction methods.

(g) If the proposed siltation structure, water impoundment, coal processing waste dam, or embankment is permanent and the:

1. (1) structure is twenty (20) feet or higher;
2. (2) drainage area above the structure is one (1) square mile or larger; or
3. (3) volume of water impounded is more than one hundred (100) acre-feet;

an application shall be submitted to the division of water, in the department of natural resources, and approval shall be obtained from the director before construction of the structure begins.

(Natural Resources Commission; 312 IAC 25-4-49; filed Jun 21, 2001, 2:53 p.m.: 24 IR 3457, eff Dec 1, 2001; filed Apr 1, 2004, 3:00 p.m.: 27 IR 2447, eff Jan 1, 2005; readopted filed May 29, 2007, 9:51 a.m.: 20070613-IR-312070146RFA; readopted filed Sep 19, 2013, 10:12 a.m.: 20131016-IR-312130125RFA; readopted filed Mar 26, 2019, 3:40 p.m.: 20190424-IR-312190011RFA; readopted filed Mar 25, 2025, 9:50 a.m.: 20250423-IR-312240574RFA)