The University of Massachusetts – Amherst compiled a list of the top 100 air polluters in America, the top 10 of which are shown here. Some of the top 10 polluters have, not surprisingly, very dirty skeletons in their closets. But others on this list are working to clean up their acts.

Although fossil fuel energy companies dominated the list, Warren Buffet’s Berkshire Hathaway and the federal government were in the top 5.

The list ranked polluters by converting the amount of greenhouse gases they produced into the “equivalent metric tons of carbon dioxide,” a measurement that equates the heat-trapping ability of a gas to that of carbon dioxide.

#1 American Electric Power

America’s top polluter, American Electric Power, accounted for nearly 2 percent of greenhouse gas emissions in the United States — pumping out the equivalent of 130,409,118 metric tons of carbon dioxide. Emissions data came from 2011, the most recent year available.

The biggest dirty skeleton in American Electric Power’s closet is the little town of Cheshire, Ohio (shown above). The company inundated the town with toxic sulfurous gas clouds and acid rain after botching pollution-control technology they had implemented at the Gavin power plant.

In 2002, the American Electric Power Company reached a settlement with most of the residents, to essentially buy them out for $20 million dollars. Many of the 221 residents agreed to leave the town and absolve the company from future property or health claims. Yet, some residents are refusing to leave, and are staying in their properties as the town is destroyed around them. As of the 2010 census, 132 people claimed residency in Cheshire.

Click here for the full list.