Should Lakes be Used for Mine Waste Disposal?

The disposal of mine waste into wetlands, lakes, and streams was common practice into the 1960s. This practice led to the pollution of some 12,000 miles of streams and 180,000 acres of lakes in the US.  This arbitrary destruction of aquatic habitat was halted by the passage of the Clean Water Act in 1972.  The Act charged EPA with regulating the discharge of pollutants into waters of the US (streams, lakes, the ocean, and some wetlands), and the Army Corps with regulating the “fill” of waters.  From 1972 until 2002 only “clean” fill could be placed in waters.  Waste could not be used as fill material. 

In 2002 the EPA and the Corps changed the definition of fill to include mine waste.  This change in the definition of fill material to include mine waste allows lakes, rivers, wetlands, and the ocean to be converted to mine waste treatment facilities (tailings ponds and waste rock dumps) with an Army Corps 404 permit. 

This regulatory rule change, done entirely administratively, threatens aquatic habitat throughout the US.  A similar administrative change to allow fisheries habitat (lakes and streams) to be converted to mine waste treatment systems was done in Canada in 2002, and since then 15 lakes/streams have been proposed for use as mine waste disposal sites.  The first lake in the US in almost 40 years, Slate Lake in Southeast Alaska, has been converted to a mine tailings impoundment. 

The significant cost savings in using a natural water body instead of a constructed impoundment will drive mine operators to use this new waste disposal opportunity, and a scenario somewhat similar to that occurring in Canada, where an average of 2-3 lakes per year have been proposed as mine waste disposal facilities, can be expected in the US – but at a reduced pace.

It is relatively simple to reverse this dangerous policy since the change was purely regulatory, not legislative.  However, making any change to environmental regulations in the polarized political atmosphere of Washington will be a difficult undertaking, regardless of the weight of the science.