Env. Canada Finds 40% Increase In Birds' Eggs Upstream From Tar Sands Operations

[Ecotruth]

1. Oilsands are not burned on site they are washed with warm water that is recycled.

Mercury is emitted to the air by human activities, such as manufacturing or burning coal for fuel, and from natural sources, such as volcanoes.

Typically, mercury is released into the atmosphere in one of three forms:

elemental mercury: can travel a range of distances, may remain in the atmosphere up to one year and may travel globally before undergoing transformation

particle-bound mercury: can fall out of the air over a range of distances

oxidized mercury (sometimes called ionic or reactive gaseous mercury (RGM)): found predominantly in water-soluble forms, which may be deposited at a range of distances from sources depending on a variety of factors including topographic and meteorologic conditions downwind of a source.

What happens to mercury after it is emitted depends on several factors:
- the form of mercury emitted
- the location of the emission source
- how high above the landscape the mercury is released (e.g., the height of the stack)
- the surrounding terrain
- the weather.

Depending on these factors, atmospheric mercury can be transported over a range of distances before it is deposited, potentially resulting in deposition on local, regional, continental and/or global scales. Mercury that remains in the air for prolonged periods of time and travels across continents is said to be in the "global cycle."

Recent emissions estimates of annual global mercury emissions from all sources, natural and anthropogenic (human-generated), which are highly uncertain, are about 4800-8300 tons per year.

U.S. anthropogenic mercury emissions are estimated to account for roughly 3 percent of the total global emissions, and the U.S. power sector is estimated to account for about 1 percent the total global emissions. EPA has estimated that about one third of U.S. emissions are deposited within the contiguous U.S. and the remainder enters the global cycle.

Current estimates are that less than half of all mercury deposition within the U.S. comes from U.S. sources, although deposition varies by geographic location. For example, compared to the country as a whole, U.S. sources represent a greater fraction of the total deposition in parts of the Northeast because of the direction of the prevailing winds.

http://www.epa.gov/hg/exposure.htm#1