PPT Slide
Notes:
In any event, there appears to be a happy ending to the Vermont Arsenic story. Concentrations dropped substantially after the end of 1989, and have now fallen below the level of Vermont’s State toxic standard. Our understanding (not well confirmed) is that there were major revisions to control equipment at both Noranda and Sudbury at about this time period (for SO2/ Acid Rain control purposes).
It would appear that there were also serendipitous benefits in terms of Arsenic emissions reductions. In any event, the Northeast States are certainly grateful (although now we aren’t sure who to thank).
Too often, in both countries, we tend to focus on a single air pollutant at a time - in our air quality measurements, emissions inventories and control strategies. How many other potential multi-pollutant effects and opportunities for “serendipitous” management strategies go unrecognized because we neglect to routinely exchange and compare data across our common border?