Potential Liability for Good Samaritans
Cleaning Up Abandoned Hardrock Mines

The Abandoned Hardrock Mine Problem

It has been estimated that there are 500,000 abandoned hardrock mine sites throughout the country.[1]  These sites impact thousands of miles of streams throughout the U.S. with acid drainage and high metal loading.[2]  Although referred to as abandoned, most of these mine sites have owners, either private individuals, corporations, or state and federal land management agencies.  They are considered abandoned, because the people or companies responsible for the mining are generally long gone or have very limited financial resources.  Thus, those directly responsible for creating problems at a site cannot be forced to fix them.

While the sheer number of abandoned hardrock mine sites seems overwhelming, many of them for one reason or another have minimal impact on rivers and streams.  For example, of the 1,500 mine sites documented in the upper Animas River watershed in southwestern Colorado, less than 5% have been deemed in need of some type of cleanup.[3]  But even 5% of the hundreds of thousands of sites throughout our nation is a large number. 

Because no financially viable, potentially responsible party (PRP) exists for many abandoned mines, certain third-parties with no responsibility have volunteered to reduce metal loading emanating from particular sites.  These third-parties, or Good Samaritans, may be state or federal agencies, watershed groups, environmental groups, mining companies or other organizations.  Typically, their goal is to improve water quality.

Reductions in metal loading may be done by remediating mine wastes, mine drainage or both.  Mine wastes (waste rock piles or tailings) may either be removed from the site to a disposal area or mill, or interned in place by adding lime to increase pH, consolidating wastes, and isolating the material from water by capping piles, diverting surface runoff, and re-vegetating. 

Mine drainage may be addressed by some combination of minimizing water entering the mine, plugging the mine, separating poor quality drainage from good to minimize flow for treatment, or treating drainage with settling ponds, wetlands, limestone drains, or some other form of passive or active treatment.  Each site must be evaluated for which options may be most practicable.

Environmental Liability

Unfortunately, Good Samaritans can incur environmental liabilities similar to property owners and operators of a mine site.  Owners and operators of abandoned hardrock mines that impact the environment are generally liable for correcting those damages under a number of state and federal environmental statutes, even if they don’t have the financial means to do so.  The two statutes most likely to apply to a number of sites are the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Clean Water Act (CWA).[4]     

CERCLA (also referred to as the Superfund law) authorizes federal agencies to control or prevent releases of hazardous substances into the environment “which present an imminent and substantial threat to the public health or welfare...”[5]  These agencies, usually EPA, may force responsible parties to control or prevent the release, or take action themselves using “Superfund” monies and later, if possible, recover the costs from responsible parties.  Recovery actions are frequently very time-consuming, costly and litigious. 

So far, most Good Samaritans have limited their potential liability under CERCLA through comfort letters, remedial actions memorandums (RAM’s), and administrative orders on consent (AOC’s).  These mechanisms, in the order listed, offer increasingly greater levels of liability protection, but at the same time add increasingly more requirements that must be met by the Good Samaritan.    

Most of the CERCLA liability protection mechanisms have been used for work on mine waste.  Virtually no Good Samaritan has been willing to work on draining mines because of potential liability stemming from the Clean Water Act (CWA). 

In the language of CWA, EPA considers draining mines as point-sources of pollution which require National Pollutant Discharge Elimination System (NPDES) permits.  Holders of NPDES permits are required to use, at minimum, the “best available technology” for removing toxic substances.[6]  For most mine drainages, meeting this standard requires a very costly active treatment plant.  Discharges must also meet existing stream standards and Total Maximum Daily Loads (TMDL).

So far, very few abandoned hardrock mines have been required to get NPDES permits, because in most cases, it is impracticable.  Many sites have no road access, especially in winter, no electrical power, and no flat areas for treatment facilities.  Most property owners do not have the resources to build treatment plants and operate them essentially forever.  And the sheer number of draining mines would overwhelm the permitting agency.     

The problem for Good Samaritans is that unlike agreements that they might negotiate with a regulatory agency to minimize CERCLA liability, agreements under CWA may be challenged by citizen suits.  A citizen suit could force the regulatory agency to issue a NPDES permit to anyone who has had anything to do with impacting or treating mine drainage.[7]  Although partial treatment of mine drainage (such as a limestone drain) may be practical and cost-effective, the exposure to the potential liability of building an active treatment plant that meets NPDES requirements and operating it in perpetuity is too much of a risk for most Good Samaritans to take.

Legislative Fixes

Since 1994, when this liability issue first arose, there have been a number of attempts to pass federal legislation to reduce liability for Good Samaritans who are voluntarily trying to clean up abandoned hardrock mine sites.  Most of these efforts have focused on amending CWA to create a new NPDES permit specifically for Good Samaritans working on abandoned hardrock mines.  Creating new types of NPDES permits is not a new concept.  Congress added new NPDES permits to CWA for stormwater in 1987, and combined sewer overflows in 2000.[8] 

So far, lack of support from either environmental or mining interests has prevented any legislation from becoming law.  Environmental interests are wary of tampering with environmental laws and want a number of strict limitations placed upon Good Samaritans.  They are very concerned about not reducing liability for those who already have an obligation to do clean up.  Mining interests point to the voluntary nature of Good Samaritan actions and want broad liability protections in order to apply their considerable financial and technical resources to abandoned mine cleanup.  In the middle are watershed groups that want to protect and improve water quality in their watersheds.  They want to insure that those responsible for damages are not let off the hook, yet they recognize that the new permitting requirements must be flexible enough so that Good Samaritans will feel comfortable to voluntarily take on meaningful clean up projects.

In addition to legislative fixes, EPA has released a template AOC with the hope of making liability relief under CERCLA easier to implement.  The template is also intended to help mollify concerns of potential Good Samaritans, particularly the mining industry, and to alleviate the need for legislative changes in CERCLA liability.  It remains to be seen if the template will have its desired effect.  The AOC will have no effect on the liability problems related to CWA.

Text similar to the above appeared in an article in the September 2007 issue of Water Resources IMPACT published by the American Water Resources Association.