As noted in prior posts, EPA has proposed national standards for mercury and other toxic pollutant emissions from power plants. See http://www.epa.gov/airquality/powerplanttoxics/. Now Guam and 25 states have filed a challenge to the regulations.
The EPA is under court order to finalize the so-called maximum achievable control technology rule for utilities on November 16, 2011. But the lawsuit seeks to delay the finalization of the rule, which is designed to reduce emissions of mercury and acid gases from power plants fired by coal and oil, until at least November 16, 2012. The advocates for the lawsuit claim that EPA is seeking to shutter many coal-fired power plants and that the regulations would jeopardize the U.S. power supply.
Information about the sources of mercury and its impact on the environment can be found at http://www.usgs.gov/themes/factsheet/146-00/ and http://www.epa.gov/hg/about.htm.
As also noted in prior posts, EPA proposed changes to ozone standards. See http://www.epa.gov/glo/actions.html. However, recently, the Obama administration withdrew the proposed new rules. See http://thehill.com/blogs/e2-wire/677-e2-wire/179357-white-house-shelves-smog-rule-in-huge-defeat-for-green-groups.
Now, the American Lung Association et al have filed suit in the D.C. Circuit challenging the withdrawal. The proposed rules would have reduced the ozone level from 75 ppb to 70 ppb, which was at the high end of what was recommended by an EPA scientific advisory committee. A link to the lawsuit can be found embedded in an article at http://www.fairwarning.org/2011/10/environmentalists-sue-over-epas-retreat-on-ozone-rules/.