Oklahoma Administrative Code
Title 460 - Department of Mines
Chapter 20 - The Permanent Regulations Governing the Coal Reclamation Act of 1979
Subchapter 43 - Permanent Program Performance Standards: Surface Mining Standards
Section 460:20-43-10 - Diversions

(1) With the approval of the Department, any flow from mined areas abandoned before May 3, 1978, and any flow from undisturbed areas or reclaimed areas, after meeting the criteria of Section 460:20-43-12 for siltation structure removal, may be diverted from disturbed areas by means of temporary or permanent diversions. All diversions shall be designed to minimize adverse impacts to the hydrologic balance within the permit and adjacent areas, to prevent material damage outside the permit area and to assure the safety of the public. Diversions shall not be used to divert water into underground mines without approval of the Department under Section 460:20-43-8(i).

(2) The diversion and its appurtenant structures shall be designed, located, constructed, maintained and used to:

(3) Temporary diversions shall be removed promptly when no longer needed to achieve the purpose for which they were authorized. The land disturbed by the removal process shall be restored in accordance with this part. Before diversions are removed, downstream water-treatment facilities previously protected by the diversion shall be modified or removed, as necessary, to prevent overtopping or failure of the facilities. This requirement shall not relieve the operator from maintaining water-treatment facilities as otherwise required. A permanent diversion or a stream channel reclaimed after the removal of a temporary diversion shall be designed and constructed so as to restore or approximate the premining characteristics of the original stream channel including the natural riparian vegetation to promote the recovery and the enhancement of the aquatic habitat.

(4) Temporary diversions shall be constructed to pass safely the peak runoff from a precipitation event with a 2-year, 6-hour recurrence interval or a larger event as specified by the Department.

(5) To protect fills and property and to avoid danger to public health and safety permanent diversions shall be constructed to pass safely the peak runoff from a 6-hour, 10-year precipitation event or a larger event as specified by the Department. Permanent diversions shall be constructed with gently sloping banks that are stabilized by vegetation. Asphalt, concrete or other similar linings shall be used only when approved by the Department to prevent seepage or to provide stability.

(6) Diversions shall be designed, constructed and maintained in a manner which prevents additional contributions of suspended solids to streamflow and to runoff outside the permit area to the extent possible using the best technology currently available. Appropriate sediment control measures for these diversions may include, but not be limited to maintenance of appropriate gradients, channel linings, revegetation, roughness structures, and detention basins.

(7) No diversion shall be located so as to increase the potential for landslides. No diversion shall be constructed on existing landslides unless approved by the Department.

(8) When no longer needed, each temporary diversion shall be removed, and the affected land regraded, topsoiled, and revegetated in accordance with these Regulations.

(9) Diversion design shall incorporate the following:

(1) Diversion of perennial and intermittent streams within the permit area may be approved by the Department after making the finding relating to stream buffer zones that the diversion will not adversely affect the water quantity and quality and related environmental resources of the stream.

(2) The design capacity of channels for temporary and permanent stream channel diversions shall be at least equal to the capacity of the unmodified stream channel immediately upstream and downstream from the diversion.

(3) The requirements of (a) (2) (B) of this Section shall be met when the temporary and permanent diversions for perennial and intermittent streams are designed so that the combination of channel, bank and flood-plain configuration is adequate to pass safely the peak runoff of a 10-year, 6-hour precipitation event for a temporary diversion and a 100-year, 6-hour precipitation event for a permanent diversion.

(4) The design and construction of all stream channel diversions of perennial and intermittent streams shall be certified by a qualified registered professional engineer as meeting the performance standards of this Subchapter and any design criteria set by the Department.

(5) Flow from perennial and intermittent streams within the permit area may be diverted, if the diversions:

(6) When streamflow is allowed to be diverted, the stream channel diversion shall be designed, constructed, and removed, in accordance with the following:

(7) When no longer needed to achieve the purpose for which they were authorized, all temporary stream channel diversions shall be removed and the affected land regraded and revegetated in accordance with Sections 460:20-43-9, 460:20-43-11, 460:20-43-37 through 460:20-43-40 and 460:20-43-43 through 460:20-43-46. At the time diversions are removed downstream water treatment facilities previously protected by the diversion shall be modified or removed to prevent overtopping or failure of the facilities. This requirement shall not relieve the operator who conducts the surface mining activities from maintenance of a water treatment facility required under this Subchapter of the permit.

(8) When permanent diversions are constructed or stream channels restored, after temporary diversions, the operator shall:

(1) Miscellaneous flows, which consist of all flows except for perennial and intermittent streams, may be diverted away from disturbed areas if required or approved by the Department. Miscellaneous flows shall include ground-water discharges and ephemeral streams.

(2) The design, location, construction, maintenance, and removal of diversions of miscellaneous flows shall meet all of the performance standards set forth in Subsection(a) of this Chapter:

(3) The requirements of (a) (2) (B) of this Section shall be met when the temporary and permanent diversions for miscellaneous flows are designed so that the combination of channel, bank and flood-plain configuration is adequate to pass safely the peak runoff of a 2-year, 6-hour precipitation event for a temporary diversion and a 10-year, 6-hour precipitation event for a permanent diversion.