Mining

Why We Care:

In 2012, at the urging of Canadian-based J.D Irving Company, Maine lawmakers passed a law that, among other things, weakens water quality protections for a specific type of mining in Maine (metallic mineral mining also known as sulfide mining).

Sulfide mining could have dramatic implications on Maine's clean water and wildlife habitat, and Maine Conservation Voters continues to advocate for strengthening and clarifying clean water standards in any rules or legislation on this issue. Additionally, we advocate for strong assurances that taxpayers will never be left footing the bill for clean up costs if sulfide mines are built in the state.

Background: Metals such as copper, silver, gold, nickel and zinc are often found in rock know as sulfide ores. Sulfide mining is the process of extracting these metals from rock deposits. The process almost always involves carving large open pits into the landscape to expose ore-bearing rock. The rock is then pulverized so the desirable metals can be retrieved.

Pollution from this type of mining presents significant risks to the environment. When sulfides in rock are excavated and exposed to water and air in the mining process, a chemical reaction creates sulfuric acid, which is highly corrosive. When it gets into ground and surface waters, it destroys water quality and kills aquatic life. The result of this process is known as acid mine drainage (AMD).

Additionally, the process of pulverizing rock to expose desirable metals can also unearth a host of toxic heavy metals like lead, mercury, and copper sulfate. Water can then leach these metals out of the rocks into nearby waters, and the acidic conditions created by the AMD make this leaching even worse. The signature of AMD is a slimy, orange coating (precipitate) that builds up in the beds of affected waterways.

You can learn more about this issue by examining the related bills listed here, noting how your legislators voted, or visiting www.MaineMiningWatch.org.