Current through Register Vol. 35, No. 11, June 11, 2024
Section 20.6.7.18 - GENERAL OPERATIONAL REQUIREMENTSA.Planning for closure. To the extent practicable, copper mine facility units shall be designed and operated in a manner that considers implementation of the copper mine facility closure plan submitted pursuant to 20.6.7.33 NMAC including: (1) identifying material that is suitable for use to construct covers and, when feasible, segregating that material from other mined materials to preserve it for use to construct covers; and(2) consideration of closure grading and drainage plans in the design and construction of leach stockpiles, tailings impoundments, waste rock stockpiles, and other copper mine facilities.B.Construction requirements. A permittee shall meet the following requirements for construction of a liner system for the containment of water contaminants, including repair or relining of a liner system. (1) A permittee shall notify the department at least five working days before starting construction or repair or relining to allow for an inspection by the department, except in the case of an emergency repair. If an emergency repair is necessary, the permittee shall notify the department within 24 hours of starting the repair.(2) A permittee shall submit to the department a construction certification report bearing the seal and signature of a licensed New Mexico professional engineer, when required by the New Mexico Engineering and Surveying Practice Act, Sections 61-23-1 through 61-23-33 NMSA 1978, and the rules promulgated under that authority, verifying that installation and construction was completed pursuant to Subsections C and D of 20.6.7.17 NMAC. The construction certification report shall include as-built drawings, final specifications, final capacity calculations and the CQA/CQC report.(3) The construction certification report shall be submitted to the department before discharging or placing ore or wastes in a liner system.C.Notice of mining operations and discharge. A permittee shall provide written notice to the department of the commencement, or recommencement of operations as follows. (1)For new copper mine facilities.(a)Commencement of construction. A permittee shall provide written notice to the department a minimum of 30 days before commencing construction of units covered by a permit issued pursuant to the copper mine rule.(b)Commencement of discharge. A minimum of 30 days prior to discharging or emplacement of ore or waste rock in a constructed impoundment, stockpile, or tailings impoundment a permittee shall provide written notice to the department of the anticipated date that discharge or emplacement of ore or waste rock will commence. A permittee shall provide written verification to the department of the actual date of commencement within 30 days of commencement.(2)For existing copper mine facilities.(a)Commencement of a new discharge. A minimum of 30 days prior to discharging or emplacement of ore or waste in a newly constructed impoundment, stockpile, or tailings impoundment the permittee shall provide written notice to the department of the anticipated date that discharge or emplacement of ore or waste will commence. A permittee shall provide written verification to the department of the actual date of commencement within 30 days of commencement.(b)Recommencement of mining. If a permittee is on standby pursuant to the Mining Act, a permittee shall provide written notice to the department indicating the planned date of recommencement of operations at a copper mine facility that include operation of units covered by a permit issued pursuant to the copper mine rule. Written notification shall be submitted to the department a minimum of 30 days prior to the date mining is to recommence.D.Stormwater management. A permittee shall divert and manage stormwater from the open pit, leach stockpiles, waste rock and tailings impoundments and other copper mine facility areas containing material that could generate or release water contaminants in accordance with a stormwater management plan as required by Paragraph (4) of Subsection C of 20.6.7.17 NMAC.E.Flow meters. A permittee shall employ a flow metering system that uses flow measurement devices (flow meters, weirs or other department approved method) to measure the volume of process water and tailings discharged at a copper mine facility as follows. (1)Flow meter installation. Flow meters shall be installed in accordance with the flow meter plans submitted with the application for a new, renewed or modified discharge permit pursuant to Paragraph (5) of Subsection C of 20.6.7.17 NMAC, and this section. Flow meters shall be permanently labeled with meter identification nomenclature, and the month and year of meter installation.(2)Flow meter inspection and maintenance. A permittee shall visually inspect flow meters on a monthly basis for evidence of malfunction. If a visual inspection indicates a flow meter is not functioning to measure flow, the permittee shall repair or replace the meter within 30 days of or as soon as practicable following discovery. The repaired or replaced flow meter shall be installed and calibrated pursuant to this subsection. The permittee shall submit a report of repaired or replaced meters to the department in the subsequent monitoring report which shall include: (a) information on repairs including a description of the malfunction; a statement verifying the repair, and a description of calibration of the flow meter pursuant to Paragraph (3) of this subsection.(b) for replacement meters, information demonstrating that the device is in accordance with the plan for flow metering devices submitted pursuant to Paragraph (5) of Subsection C of 20.6.7.17 NMAC, and that the device has been calibrated pursuant to Paragraph (3) of this subsection.(3)Flow meter calibration. All flow meters required under the copper mine rule shall be calibrated to have their accuracy ascertained according to the flow metering plan submitted pursuant to Paragraph (5) of Subsection C of 20.6.7.17 NMAC and the approved discharge permit. Flow meters shall be calibrated to within plus or minus ten percent of actual flow.(4)Excluded flow meters. A permittee may utilize additional flow meters not required by the copper mine rule and those flow meters are not subject to the copper mine rule requirements.F.Impoundments.(1)New impoundments. Construction of an impoundment pursuant to a discharge permit issued after the effective date of the copper mine rule shall be performed in accordance with the liner, design, and construction requirements of Subsection D of 20.6.7.17 NMAC.(2)Existing impoundments. An impoundment authorized by a discharge permit issued prior to the effective date of the copper mine rule and in existence on the effective date of the copper mine rule that does not meet the requirements of Paragraph (3) of Subsection D of 20.6.7.17 NMAC may continue to receive process water or impacted stormwater provided the requirements of Subparagraphs (a) and (b) or (c) of this paragraph are met or the impoundment is located within the open pit surface drainage area. If the requirements of Subparagraphs (a) and (b) or (c) of this paragraph are not met, the impoundment shall be replaced or improved in accordance with the liner, design, and construction requirements of Subsection D of 20.6.7.17 NMAC.(a) Ground water monitoring data from monitoring wells downgradient of the impoundment indicates that the impoundment is functioning as designed.(b) The impoundment has integrity and is capable of maintaining integrity for its operational life.(c) The impoundment is covered by a variance granted pursuant to 20.6.2.1210 NMAC.(3)Impoundment inspection and maintenance. A permittee shall maintain impoundments to prevent conditions which could affect the structural integrity of the impoundments and associated liners during active operations. Such conditions include, but are not limited to, erosion damage; animal burrows or other animal damage; the presence of vegetation including aquatic plants, weeds, woody shrubs or trees growing within five feet of the top inside edge of a sub-grade impoundment, within five feet of the toe of the outside berm of an above-grade impoundment, or within the impoundment itself; evidence of seepage; evidence of berm subsidence; and the presence of large debris or large quantities of debris in the impoundments. A permittee shall inspect impoundments and surrounding berms on a quarterly basis to ensure proper condition and control vegetation growing in and around the impoundments in a manner that is protective of the liners. Within 24 hours of discovery, a permittee shall report to the department any evidence of damage that threatens the structural integrity of a berm or liner of an impoundment or that may result in an unauthorized discharge. A permittee is not required to report routine berm maintenance to the department.(4)Freeboard. The fluid level elevation in an impoundment shall be maintained such that a minimum of two feet of freeboard is preserved within the impoundment at all times.(5)Leak collection system inspection and maintenance: A permittee shall inspect and maintain impoundments utilizing primary and secondary liners and equipped with leak collection systems as follows:(a) liquid accumulation within the sump of the leak collection system shall be returned to the respective impoundment or the process water system utilizing an automatically activated pump or other engineered design approved by the department to minimize hydraulic head on the secondary liner by insuring the interstitial space between the liners does not become saturated; and(b) the permittee shall inspect the sump(s), dedicated pump(s), any automated pump activation system, any automated alarm system and totalizing flow meter associated with the leak detection and collection system on a monthly basis for evidence of malfunction; if an inspection indicates malfunction of any of these components, the permittee shall repair the component(s) within 30 days of discovery or shall retain a record of why the repair took longer; the permittee shall notify the department of component malfunctions and repairs made in the subsequent quarterly report.20.6.7.18 NMAC - N, 12/1/13