The Op-Ed “Science is clear: Mine would kill Bristol Bay” [Aug. 10, Opinion] is correct: If the mining operation is constructed, the question is not if there will eventually be acid mine drainage that will contaminate Bristol Bay but when. As the authors state: “Threats rise exponentially over the long-term …”

In the late 1980s, I consulted for a company examining the risks for the British Columbia government of permitting a similar mining operation, an analogous project that fortunately was never approved. And a portion of my professional life was spent teaching the principles of risk analysis to students. By analogy, would the Environmental Protection Agency of today approve the storage of nuclear wastes in the single-walled tanks at Hanford that have leaked radioactive wastes into the Columbia River?

Norman McCormick, Seattle, professor emeritus, University of Washington