Posted on October 29, 2014 by Thomas Hnasko
The unfortunate fact about copper mining is that it just cannot be done without impacting groundwater. This inevitable result occurs because of the massive excavations extending below groundwater elevations and the leaching of contaminants through the process of capturing copper. Most western mining states, including Arizona, have recognized this inevitable consequence and have crafted a “point of compliance” system where groundwater quality standards must be achieved at some designated point beyond the active mining site. Previously, the New Mexico Environment Department dealt with quality exceedances at active mining sites either by issuing variances from compliance requirements under the New Mexico Water Quality Act, or by simply ignoring the problem altogether. The Copper Mine Rule has been promoted as a pragmatic response to the cumbersome administrative variance procedure.
Under the New Mexico Water Quality Act, groundwater compliance must be achieved at any “place of withdrawal for present or reasonably foreseeable future use.” This jurisdictional threshold is markedly different than the jurisdictional standard for surface water discharges, which requires compliance precisely at the point of discharge into a body of surface water. The Copper Mine Rule recognizes that groundwater directly beneath an active mine site would not be available for use during the period of active mining operations and thus would not qualify as a “place of withdrawal” where groundwater standards must be met. Similar to the “point of compliance” approach taken by other states, the New Mexico Copper Mine Rule requires that groundwater standards must be achieved at monitoring well locations placed as close as practicable around the perimeter of the active mine site.
The Copper Mine Rule has been appealed by various NGOs and by the New Mexico Attorney General. The Attorney General contends on appeal that any determination of a “place of withdrawal” must be made on a case-by-case basis, rather than through a rule-making procedure. Interestingly, the Attorney General originally represented the New Mexico Water Quality Control Commission (“WQCC”) when it adopted the Copper Mine Rule, but abruptly reversed course and has lodged an appeal against the Rule for which it provided representation to the WQCC. As part of the response to the Attorney General’s appeal, the WQCC has filed a motion seeking to disqualify the Attorney General, based on a conflict of interest, from taking positions adverse to its former client. The matter is presently pending before the New Mexico Court of Appeals.
Tags: copper mining, groundwater, New Mexico Water Quality Act
State | Water | Water Quality Standards