Performance and reclamation standards and requirements

The land surface of the permit area will be restored as nearly as possible to its original condition unless conflicting with the approved postmining land use. Each reclamation plan must be developed to meet the site-specific characteristics of the mining operation and the site. 1. Most appropriate technology and best management practices. The mining operation and the reclamation plan shall be designed and operated using the most appropriate technology and the best management practices. 2. Contemporaneous reclamation. Contemporaneous reclamation is required to the maximum extent practicable and in a manner that is consistent with the approved reclamation plan. All reclamation work must be completed within three years of completion of mining. 3. Assure protection. The mining operation and completed reclamation shall meet the following requirements established to assure protection of human health and safety, the environment, wildlife, and domestic animals. a. Signs, markers and safeguarding. Measures will be taken to safeguard the public to prevent falls from highwalls or pit edges. Depending on site-specific characteristics, the following measures shall be required: (1) Posting warning signs in locations near hazardous areas; (2) Restricting access to hazardous areas; (3) Marking the permit area boundaries; (4) Posting a sign at the main entrances giving a telephone number of a person to call in the event of emergencies related to the mine; or (5) Other measures as needed to protect human safety. b. Wildlife protection. Measures shall be taken to minimize adverse impacts on wildlife and important habitat. Based on site-specific characteristics, the following measures will be required: (1) Restricting access of wildlife and domestic animals to toxic chemicals or otherwise harmful materials; (2) Minimizing harm to wildlife habitat during mining; and (3) Reclaiming areas of wildlife habitat if not in conflict with the approved postmining land use. c. Cultural resources. Cultural resources listed on or eligible for listing on the national register of historic places, and any cemeteries or burial grounds shall be protected until clearance has been granted by the appropriate authority. d. Hydrologic balance. Operations shall be planned and conducted to minimize change to the hydrologic balance in both the permit and potentially affected areas. If not in conflict with the approved postmining land use, reclamation shall result in a hydrologic balance similar to premining conditions unless nonmining impacts have substantially changed the hydrologic balance. (1) Operations shall be designed so that nonpoint source surface releases of acid or other toxic substances shall be contained within the permit area, and that all other surface flows from the disturbed area are treated to meet all applicable state and federal regulations. (2) The disturbed areas shall not contribute suspended solids above background levels, or where applicable the state department of health standards, to ephemeral, intermittent, and perennial streams. (3) To provide data to determine background levels for surface water entering the permit area, appropriate monitoring shall be conducted on drainages leading into the permit area. (4) All diversions of overland flow shall be designed, constructed, and maintained to minimize adverse impacts to the hydrologic balance and to assure the safety of the public. (a) No diversion shall be located so as to increase the potential for landslides. (b) Unless site-specific characteristics require a different standard which is included in the approved permit, diversions which have watersheds larger than ten acres shall be designed, constructed, and maintained to safely pass the peak runoff from a ten-year, twenty-four-hour precipitation event. (c) All diversion designs which have watersheds larger than ten acres shall be included in the permit application and certified by a registered professional engineer. Diversion designs shall be kept onsite or otherwise be made available, upon request, to the director for inspection. (d) When no longer needed, temporary diversions shall be removed and the disturbed area reclaimed. e. Stream diversions. When streams are to be diverted, the stream channel diversion shall be designed, constructed, and removed in accordance with the following: (1) Unless site-specific characteristics require different measures to meet the performance standard and are included in the approved permit, the combination of channel, bank and floodplain configurations shall be adequate to safely pass the peak runoff of a ten-year, twenty-hour-hour precipitation event for temporary diversions, and a hundred-year, twenty-four-hour precipitation event for permanent diversions; (2) The design and construction of all intermittent and perennial stream channel diversions shall be certified by a registered professional engineer. As-built drawings shall be completed promptly after construction and be included in the permit application and retained onsite or otherwise made available upon request to the director; and (3) When no longer needed, temporary stream channel diversions shall be removed and the disturbed area reclaimed. f. Impoundments. If impoundments are required, they shall be designed, constructed, and maintained to minimize adverse impacts to the hydrologic balance and adjoining property and to assure the safety of the public. (1) Unless site-specific characteristics require different measures to meet the performance standard and are included in the approved permit, impoundments having earthen embankments but not subject to the jurisdiction of the mine safety and health administration or the state department of health shall: (a) Have a minimum elevation at the top of the settled embankment of two feet above the water surface in the pond with the spillway flowing at the design depth; (b) Have a top width of the embankment not less than six feet; (c) Have combined upstream and downstream side slopes of the settled embankment not less than five horizontal: one vertical with neither slope steeper than two horizontal: one vertical. Slopes shall be vegetated or otherwise stabilized to control erosion; (d) Have the embankment foundation cleared of all vegetative matter, all surfaces sloped to no steeper than one horizontal: one vertical and the entire foundation area scarified; (e) Have fill material free of vegetative matter and frozen soil; (f) Have sufficient capacity for sediment storage and have sediment removed when that capacity is reached; and (g) Have spillways provided to safely discharge the peak runoff of a twenty-five-year, twenty-four-hour precipitation event, or an event with a ninety percent change of not being exceeded for the design life of the structure; or (h) Have other site-specific design criteria for embankments as long as they result in a minimum static safety factor for 1.3 with water impounded to the design level; (i) Be designed and certified by a registered professional engineer. As-built drawings shall be completed promptly after construction and be retained onsite or otherwise made available upon request to the director; and (j) If necessary for sediment control, be in place before any other disturbance to the watershed for the impoundment. (2) When no longer required, impoundments shall be graded to achieve positive drainage unless: (a) The surface estate owner has requested in writing that they be retained; (b) They are consistent with the approved reclamation plan; and (c) They are appropriate for the postmining land use for the self-sustaining ecosystem. g. Minimization of mass movement. All temporary stockpiles shall be constructed and maintained to minimize mass movement. h. Riparian and wetland areas. Disturbance to riparian and wetland areas shall be minimized during mining. Adverse effects to riparian and wetland areas shall be mitigated during reclamation unless the mitigation conflicts with the approved postmining land use. i. Roads. Roads shall be constructed and maintained to control erosion. (1) Drainage control structures shall be used as necessary to control runoff and to minimize erosion, sedimentation, and flooding. Culverts or other drainage facilities shall be installed as road construction progresses and shall be capable of safely passing a ten-year, twenty-four-hour precipitation event unless site-specific characteristics indicate a different standard is appropriate and is included in the approved permit. Culverts and drainage pipes shall be constructed and maintained to avoid plugging, collapsing, or erosion. (2) Roads to be constructed in or across intermittent or perennial streams require site-specific designs to be submitted with the permit application. (3) Permanent roads must be approved by the surface owner and be consistent with the approved postmining land use. j. Explosives. Blasting shall be conducted to prevent injury to persons or damage to property not owned by the operator. Fly rock shall be confined to the permit area. The director may require a detailed blasting plan, preblast surveys or specify blast design limits to control possible adverse effects to structures. 4. Reclamation of surface facilities. The permit area shall be stabilized, to the extent practicable, to minimize future impact to the environment and protect air and water resources. Unless otherwise approved by the department, the reclamation of surface facilities shall include the removal of all buildings, road, and structures, and the surface restored as nearly as possible to its original condition. Tailings impoundments and ponds must be reclaimed and filled in and respread with topsoil and subsoil. All grading, backfilling, and topographic reconstruction must control erosion and sedimentation, protect areas outside the affected land from slides or other damage, and minimize the need for long-term maintenance. Measures must be taken to reduce, to the extent practicable, the formation of acid and other toxic drainage that may otherwise occur following closure to prevent releases that cause federal or state standards to be exceeded. Nonpoint source surface releases for acid or other toxic substances shall be contained within the permit area. Pond and impoundment reclamation must meet the following requirements: a. Pond sludge must be chemically characterized to determine whether further treatment is necessary before disposal. Sludge must be removed for disposal at on offsite permitted solid waste facility or buried and covered onsite in a solid waste facility permitted in accordance with the applicable solid waste rules in North Dakota Administrative Code article 33-20; and b. Geomembranes must be removed from impoundments, unless it is demonstrated to the department's satisfaction that they will serve a useful function consistent with the approved postmining land use. The geomembrane material must be disposed of in a permitted landfill or may be disposed of onsite only if the operator first secures a solid waste permit in compliance with article 30-20. 5. Topsoil and subsoil. The operator shall take measures to remove and save all available topsoil and subsoil and protect it from erosion or contamination and assure that it is in a usable condition for sustaining vegetation when needed The following requirements shall be met unless site-specific characteristics mandate different requirements and those requirements are included in the approved permit. a. Topsoil and subsoil shall be sampled and analyzed for vegetation establishment suitability: (1) Sample spacing and interval shall be based on site-specific materials; and (2) Suitability will be identified by analysis based on site-specific materials. b. Revegetation must be a component of the reclamation plan and all available topsoil and subsoil must be salvaged and replaced on disturbed areas. c. Where direct distribution of topsoil and subsoil is not possible, it shall be stockpiled separately and in a manner to prevent loss of the resource. d. Topsoil and subsoil shall be distributed in a manner to establish and maintain vegetation, consistent with the approved permit. e. After distribution, topsoiled and subsoiled areas shall be stabilized to protect loss of the resource. f. Where topsoil has been stockpiled for more than one year, the operator may be required to conduct analyses to determine if amendments are necessary. 6. Erosion control. Reclamation of disturbed lands must result in a condition that minimizes erosion. Revegetated lands must not contribute suspended solids above background levels, or where applicable, the state department of health standards, to streamflow of intermittent and perennial streams. Acceptable practices to control erosion include the following: a. Stabilizing disturbed areas through land shaping, berming, or grading to final contour; b. Minimizing reconstructed slope lengths and gradients; c. Diverting runoff; d. Establishing vegetation; e. Regulating channel velocity of water; f. Lining drainage channels with rock, vegetation, or other geotechnical materials; and g. Mulching. 7. Revegetation. Revegetated lands must meet the following standards: a. Revegetation success for a return as near as possible to original condition shall be determined through comparison of ground cover, productivity, and diversity and shall be made on the basis of the following approved reference areas: (1) Foliage or basal cover and productivity of living perennial plants of the revegetated area shall be established equal to ninety percent of the reference area or equal to the approved revegetation standard using scientifically valid sampling techniques; (2) Diversity of plant life forms (woody plants, grasses, forbs) shall consider what is reasonable based on the physical environment of the reclaimed area; and (3) Woody plant species shall be established to the approved density standard. b. For areas for which the approved postmining land use is for wildlife habitat or forest land, success of vegetation shall be determined on the basis of tree or shrub stocking (density) and ground cover. (1) The ground cover of living perennial plants shall be equal to ninety percent of the native ground cover of the reference area or other approved standard and shall be adequate to minimize erosion. (2) Tree density for forest land shall have establishment rates of plant species equal to ninety percent of the approved reference area or other approved standard and shall be adequate to minimize erosion. (3) If wildlife habitat is to be the postmining land use, the operator shall select and use plant species on the reclaimed areas based on the following criteria: (a) Their proven nutritional value for fish and wildlife; (b) Their uses as cover and security for wildlife; (c) Their ability to support and enhance fish and wildlife habitat; and (d) Distribution of plant life forms to maximize benefits of edge effect, cover, and other benefits for fish and wildlife. c. Revegetation for other postmining land shall be consistent with the approved postmining land use. Site-specific standards may include standards for foliar or basal cover, production, and diversity and will be included in the approved permit.