Skip to main content

Lurking in the Shadows—Issues in Developing Historic Mine Properties: Part 1

| 4 min read
  • Email
  • Linkedin

by Jim Allen

It’s a familiar admonition to exploration geologists seeking new mineral deposits:  Look first “in the shadow of the headframe.”  For a variety of reasons, a new source of production is more likely to be found not far from where historic mining took place.  But historic mining property comes with a list of possible legal issues that require careful planning and thoughtful legal strategies.  But geologists aren’t the only potential users of land within the headframe’s shadow.  In several locations in the West, the results of former mining occupy some of the region’s most expensive real estate.  Real-estate and resort developers will encounter many of the same issues faced by miners when they begin planning a new life for former mining property.

One issue that sometimes trips up operators and developers is the application of the so-called Bevill Amendment governing on-site disposal of mining waste.  In an area with a history of mining, the headframe may cast its shadow over the resting places of a variety of mine wastes, tailings, or spills, perhaps containing acid-producing or heavy metal contaminants.  Depending on the date of the historic mining activity, these sites may have been only partially reclaimed.  In some cases, heavy-metal-bearing tailings may have been scattered for reuse as fill material or roadbase, or simply dispersed by the wind or runoff.  (One enterprising community even reportedly used mill tailings as sand for a children’s play area in the local park!)  At some older properties, these wastes were deposited long before any federal or state law regulated their content or disposal.

Since 1980, large volumes of so-called low-toxicity mining waste can be permanently disposed of onsite using an exception to federal hazardous-waste law (Subtitle C of the Resource Conservation and Recovery Act, or RCRA).  This exception, called the Bevill Amendment, permits certain mining waste to be treated as ordinary solid waste (under Subtitle D) or to be entirely free of regulation under RCRA.  Mining or mineral processing waste that is uniquely associated with primary ore extraction or benefication operations falls with the exception.  Waste derived from ancillary processing operations, or from generic industrial operations on mining sites (e.g., truck tires, engine oil, or laboratory waste) must be disposed of without benefit of the Bevill Amendment.

Mine operators have sometimes come to grief through their casual or careless attention to maintaining a Bevill waste’s exempt status.  Once that status is lost, the entire volume of waste must be handled according to RCRA’s Land Disposal Restrictions—usually requiring hauling the material to a landfill licensed to receive it.  In one common scenario, a subsequent property owner relocates or re-grades the tailings deposit, and in the process mixes it with other solid or hazardous waste.  When this happens, under EPA’s rules the entire quantity of mixed material loses its Bevill waste status, and must be treated according to RCRA’s Land Disposal Restrictions.  A second scenario involves the increasing practice of reprocessing mine wastes to recover additional metals using more modern methods.  Whether this can be done without  triggering regulatory burdens depends on the history of the material, the timing of its placement, and whether the reworking would amount to “active management” of the waste.  The prudent operator will contact hazardous-waste regulatory authorities and obtain a site-specific review of processing plans prior to physically handling the material.

One new and disturbing development involves two cases where the regulatory authority changed its mind years after making a determination that particular processing practices applied to a waste stream retained its Bevill-exempt character.  In one case, a gold mine diverted a small liquid bleed stream into its mill tailings pond, where it mixed with Bevill-exempt tailings.  The assay lab at another gold mine disposed of its fire-assay cupels (porcelain cups used in the assay process) with the mill tailings.  In both cases, the Nevada environmental authorities had confirmed that it viewed the Bevill status of the tailings to be unharmed by this practice.  Recently, EPA pressured the Nevada authorities to reverse their earlier position and initiate enforcement actions.  Both cases have recently settled under consent decrees where the operators paid substantial fines, and ceased their long-standing disposal practices for the bleed stream and assay materials.