President Bush rejected a U.S. EPA proposal that would have gone much further toward improving air quality than his pet Clean Skies Initiative, according to administration documents. To cite just one example, the EPA proposal would have limited sulfur dioxide emissions to 2 million tons per year by 2010; by contrast, the (so-called) Clear Skies plan would limit such emissions to 3 million tons per year by 2018. The White House claimed the EPA plan was unrealistic, but critics say it was rejected because it imposed too many restrictions on the energy industry. Bush continues to maintain that his plan would do more to improve air quality than the 1970 Clean Air Act and 1990 amendments (signed by Bush, Sr.), which would be replaced, but he has not yet released any details to back up that claim, and it is widely disputed by environmentalists.