As important as they can be for economic development and providing critical natural resources, extractive activities such as mining come with a cost that historically has extended well beyond the balance sheet of those who profit from the endeavor. Known as externalities, these costs are paid by society and serve to offset the total benefit the activity brings about.

As technology and awareness of those impacts and their implications have improved, these externalities have been reduced. The issue, however, remains, particularly when considering the activities of generations past. Governments have a number of tools at their disposal for addressing externalities, but they are most effective – as with most things – when employed proactively, at the outset of the activity in question. Retroactively addressing the damage said activity causes is a far more challenging issue.

One thing all parties can agree on, though, when considering some of the messier legacies left by mining activities of the past, is that there is a pressing need to clean them up. But under the Clean Water Act of 1970, those who take on such a task expose themselves to liability for any harm the mine has caused.

Many attempts to revise the legislation to protect the good Samaritans who commit to mine cleanup have failed over the last several decades. But a new attempt to provide good Samaritan protections shows some hope for success – at least for now.

Hard-rock mining in the West has wrought significant damage to water and soils, creating polluted environments that harm drinking-water supplies, plants and wildlife. Estimates of up to 160,000 such mines across the West, including 7,300 in Colorado alone, suggest the scope of the problem.

With the Clean Water Act’s current requirement that those who embark upon cleanup efforts be responsible for making the mines 100 percent pollution-free, the risk of addressing it is far too much for well-intended groups or individuals to assume. That concern has been the stumbling block for a group attempting to address pollution from the Red and Bonita Mine that has diminished water quality in Cement Creek, a tributary to the Animas River near Silverton.

Colorado Sens. Mark Udall and Michael Bennet joined Sen. Barbara Boxer, D-Calif., in signing a letter to the Environmental Protection Agency. In it they asked the agency to articulate what incentives and protections are available to groups or individuals that undertake mine cleanup efforts under the Clean Water Act’s current provisions.

This administrative approach could provide an opportunity to clarify the mine cleanup liability issues that have limited action, despite the strong desire to address the issue. Udall has sponsored good Samaritan protection legislation, as well, and has long been an advocate for revising the situation to the benefit of watersheds, communities and wildlife across the West.

It is likely that a satisfying solution will require both administrative and legislative action to ensure that all potential liability issues are adequately addressed. That also will mean including ensuring that those responsible for the harmful mining activity be held accountable where they can be identified.

It is well past time to address the mining pollution that began in the West more than a century ago, and with the will firmly in place, lawmakers now must find a clear way to implement it. There are too many resources at stake to allow the issue to languish any longer.