https://www.washingtonpost.com/news/politics/wp/2017/08/24/what-trump-has-undone/
Withdrew from the Paris climate agreement.
Blocked the Clean Power Plan. The plan implemented under Obama focused on reducing greenhouse gas emissions from power plants. In October, The Post reported that the administration would seek to repeal it entirely.
Suspended a rule limiting methane leaks from drilling on federal land. Methane is a much more potent greenhouse gas than carbon dioxide.
Ended a study on the health effects of mountaintop-removal mining. The process involves blasting away the tops of hills and mountains to get at coal seams under the surface.
Rescinded a rule mandating that rising sea levels be considered when building public infrastructure in flood-prone areas.
Reversed an Obama ban on drilling for oil in the Arctic.
Announced a reduction in the scale of several national monuments. In April, Trump signed an executive order ordering a review of monuments added in the past 20 years, opening up the possibility that some areas previously set aside would have that status revoked. Last month, Trump announced plans to reduce the size of two, one after lobbying from a uranium company.
Ignored a deadline to implement a rule regulating smog.
Withdrew a rule regulating fracking on public land.
Announced plans to reconsider controversial protections for the sage grouse in western states. The bird’s habitat has been reduced as sagebrush has been removed in places that are being developed, often for oil and grass drilling. While not officially endangered, conservation groups worry about the sage grouse’s fate.
Postponed an EPA rule that would have had chemical plants better evaluate and inform the public about possible safety issues. This decision, made in June, drew new attention after Hurricane Harvey flooding led to an explosion at a facility near Houston.
Rejected a proposed ban on the pesticide chlorpyrifos. The month after this decision, a group of farmworkers were sickened by exposure to the chemical.
Reversed a ban on plastic bottles at national parks.
Repealed a ban on lead bullets. The bullets were banned under Obama because the lead can poison wildlife.
Rescinded a limit on the number of sea animals that can be trapped or killed in fishing nets.
Delayed and potentially rolled back automotive fuel efficiency standards.
Began repeal of a rule that would weaken emissions standards for some truck components.
Repealed the Waters of the United States rule. This rule expanded the definition of water bodies that were protected by the Environmental Protection Agency.
Ended a rule banning dumping waste from mining into streams.
Reversed a rule banning hunting bears and wolves. The ban applied to federal refuges in Alaska and prohibited hunting predators using certain methods.
Repealed a rule that would have overhauled the federal land management process.
Removed more than a dozen academics from the EPA’s Scientific Advisory Board.
Removed a bike-sharing station at the White House.
There has been much more in the years since - including today's announcement about opening up the Tongass to logging - but I don't have a handy list in one place, sad to say.
I imagine there are other people/organizations keeping track - I hope!
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