N.M. Admin. Code § 19.8.20.2010

Current through Register Vol. 36, No. 1, January 14, 2025

Section 19.8.20.2010 - HYDROLOGIC BALANCE: WATER QUALITY STANDARDS AND EFFLUENT LIMITATIONS

A. Treatment of disturbed area surface flow.

(1) With the exception of surface flow leaving the disturbed area with respect to which area the operator has complied with the requirements of 19.8.20.2009 NMAC, all surface flow that leaves the disturbed area shall be passed through a sedimentation pond or series of sedimentation ponds or other treatment facilities before leaving the permit area. Any discharge of water from underground workings to surface waters which does not meet the effluent limitations of 19.8.20 NMAC shall also be passed through a sedimentation pond, a series of sedimentation ponds, or a treatment facility before leaving the permit area.

(2) Sedimentation ponds and other treatment facilities shall be maintained until the disturbed area has been regraded and erosion on the regraded area has been controlled.

(3) Sedimentation ponds and treatment facilities for discharges from underground workings shall be maintained until either the discharge continuously meets the effluent limitations of 19.8.20 NMAC without treatment or until the discharge has permanently ceased.

(4) The director may grant exemptions from these requirements only when:

(a) the disturbed drainage area within the total disturbed area is small; and

(b) the person who conducts the surface coal mining operations demonstrates that sedimentation ponds and treatment facilities are not necessary for drainage from the disturbed drainage areas to meet the effluent limitations in Paragraph (8) of Subsection A of 19.8.20.2010 NMAC and the applicable state and federal water quality standards for downstream and receiving waters.

(5) For the purposes of 19.8.20 NMAC only, disturbed area shall not include those areas in which only diversion ditches, sedimentation ponds, or roads are installed in accordance with 19.8.20 NMAC and the upstream area is not otherwise disturbed by the person who conducts the surface coal mining operations.

(6) Sedimentation ponds required by 19.8.20 NMAC shall be constructed in accordance with 19.8.20.2014 NMAC in appropriate locations before beginning any surface coal mining operations in the drainage area to be affected.

(7) Where the sedimentation pond or series of sedimentation ponds is used so as to result in the mixing of drainage from the disturbed areas with drainage from other areas not disturbed by current surface coal mining and reclamation operations, the permittee shall achieve the effluent limitations set forth below for all of the mixed drainage when it leaves the pond discharge point.

(8) Discharges of water from areas disturbed by surface mining activities and underground mining activities shall be made in compliance with all applicable state and federal water-quality laws and regulations and with the effluent limitations for coal mining promulgated by the U.S. environmental protection agency set forth in 40 CFR Part 434.

B. A discharge from the disturbed areas is not subject to the effluent limitations of 19.8.20 NMAC, if:

(1) the discharge is demonstrated by the discharger to have resulted from a precipitation event equal to or larger than a 10-year 24-hour precipitation event; and

(2) the discharge is from facilities designed, constructed, and maintained in accordance with the requirements of 19.8.20 NMAC.

C. Adequate facilities shall be installed, operated, and maintained to treat any water discharged from the disturbed area so that it complies with all federal and state laws and regulations and the limitations of 19.8.20 NMAC. If the pH of water to be discharged from the disturbed area is less than 6.0, an automatic lime feeder or other automatic neutralization process approved by the director shall be installed, operated, and maintained. The director may authorize the use of a manual system, if he finds that:

(1) flow is infrequent and presents small and infrequent treatment requirements to meet applicable standards which do not require use of an automatic neutralization process; and

(2) timely and consistent treatment is ensured.

N.M. Admin. Code § 19.8.20.2010

11-29-97; 19.8.20.2010 NMAC - Rn, 19 NMAC 8.2.20.2010, 9-29-2000; A, 12-31-2007; A, 08-31-2010