President Trump, with help from his administration and Republicans in Congress, has reversed course on nearly two dozen environmental rules, regulations and other Obama-era policies during his first 100 days in office.
Citing federal overreach and burdensome regulations, Mr. Trump has prioritized domestic fossil fuel interests and undone measures aimed at protecting the environment and limiting global warming.
WHO WANTED IT CHANGED? Republicans in Congress criticized President Barack Obama for delaying construction of the pipeline — which they argued would create jobs and stimulate the economy — after protests led by the Standing Rock Sioux Tribe. Mr. Trump ordered an expedited review of the pipeline, and the Army approved it.
WHO WANTED IT CHANGED? The coal industry said the rule was overly burdensome, calling it part of the war on coal. Congress passed a bill revoking the rule, which Mr. Trump signed into law.
WHO WANTED IT CHANGED? Republican officials from 11 states wrote a letter to Scott Pruitt, the administrator of the Environmental Protection Agency, saying the rule added costs and paperwork for oil and gas companies. The next day, Mr. Pruitt revoked the rule.
WHO WANTED IT CHANGED? Republicans, along with oil, gas and steel industry groups, opposed Mr. Obama’s decision to block the pipeline, arguing that the project would create jobs and support North American energy independence. After the pipeline company reapplied for a permit, the Trump administration approved it.
WHO WANTED IT CHANGED? Republicans and fossil fuel industry groups opposed the updated planning rule for public lands, arguing that it gave the federal government too much power at the expense of local and business interests. Congress passed a bill revoking the rule, which Mr. Trump signed into law.
WHO WANTED IT CHANGED? Coal companies weren’t thrilled about the Obama administration’s three-year freeze on new leases on public lands pending an environmental review. Ryan Zinke, the interior secretary, revoked the freeze and review, though he promised to set up a new advisory committee to review coal royalties.
WHO WANTED IT CHANGED? The company that sells the insecticide, Dow Agrosciences, strongly opposed a risk analysis by the Obama-era E.P.A., which found that the insecticide Chlorpyrifos poses a risk to fetal brain and nervous system development. Mr. Pruitt rejected the E.P.A.’s previous analysis and denied the ban, saying that the chemical needed further study.
WHO WANTED IT CHANGED? Alaskan politicians opposed the law, which prevented hunters from shooting wolves and grizzly bears on wildlife refuges, arguing that the state, not the federal government, has authority over those lands. Congress passed a bill revoking the rule, which Mr. Trump signed into law.
WHO WANTED IT CHANGED? Republicans in Congress opposed the guidelines, which advised federal agencies to account for greenhouse gas emissions and potential climate effects in environmental impact reviews. They argued that the government lacked the authority to make such recommendations, and that it would be impossible to plan for the uncertain effects of climate change.
WHO WANTED IT CHANGED? Farmers, real estate developers, golf course owners and many Republicans opposed this clarification of the Clean Water Act, arguing that it created regulatory burdens. Mr. Trump called it a “massive power grab” by the federal government and instructed the E.P.A. and the Army to conduct a review.
WHO WANTED IT CHANGED? Automakers said it would be difficult and costly to meet fuel economy goals they had agreed upon with the Obama administration and noted rising consumer demand for sport utility vehicles and trucks. A standards review had been completed by the Obama administration before Mr. Trump took office, but the auto industry argued that it was rushed. The E.P.A. and Department of Transportation have reopened the review.
WHO WANTED IT CHANGED? Coal companies and Republican officials in many states strongly opposed the plan, which set strict limits for carbon dioxide emissions from existing coal- and gas-fired power plants. Republicans argued the plan — Mr. Obama’s signature climate change policy — posed a threat to the coal industry, and had mounted a legal challenge. Mr. Trump signed an executive order instructing the E.P.A. to review and re-evaluate the rule. An appeals court recently approved the Trump administration’s request to put the lawsuit on hold during the review process.
WHO WANTED IT CHANGED? Utility and fossil fuel industry groups opposed the rule, which limited the amount of toxic metals — arsenic, lead, and mercury, among others — power plants could release into public waterways. Industry representatives said complying with the guidelines would be extremely expensive. The E.P.A. has delayed compliance deadlines while it reconsiders the rule, which had been challenged in court.
WHO WANTED IT CHANGED? Lobbyists for the oil and gas industries petitioned Mr. Pruitt to reconsider the rule, which went into effect last August, limiting emissions of methane, smog-forming compounds and other toxic pollutants from new and modified oil and gas wells. They argued the rule was technologically infeasible.
WHO WANTED IT CHANGED? Congressional Republicans said the Antiquities Act, which allows presidents to designate national monuments on federal land, had been abused by previous administrations. Mr. Obama used the law to set aside more than 4 million acres of land and several million square miles of ocean for protection.
WHO WANTED IT CHANGED? Lobbyists for the oil industry were opposed to Mr. Obama’s use of the Outer Continental Shelf Lands Act to permanently ban offshore drilling along the Atlantic coast and much of the ocean around Alaska, as well as regulations around oil rig safety.
WHO WANTED IT CHANGED? The rule required tire manufacturers and retailers to provide consumers with information about replacement car tires. The tire industry opposed several aspects of the rule, but had been working with the government to refine it. The Trump administration withdrew the proposed rule from consideration, but has not confirmed whether it may be reinstated.
WHO WANTED IT CHANGED? The oil and gas industry said that the rule, which required companies to control methane emissions on federal or tribal land by capturing rather than burning or venting excess gas, would have curbed energy development. The House voted to revoke the rule under the Congressional Review Act, and Senate Republicans have until May 8 to take action.
WHO WANTED IT CHANGED? Lobbyists for the fossil fuel industry said the changes, meant to ensure fair pricing on oil, gas and coal on federal or tribal land and to reduce costs, were redundant since the government already has the power to impose penalties. They also argued that it created a lot of uncertainty in the market.
WHO WANTED IT CHANGED? Chemical, agricultural and power industry groups said that the new rule, a response to a 2013 explosion at a fertilizer plant that killed 15 people, did not increase safety and would have undermined oversight. The rule is delayed until June 19, and industry groups have said that they may sue.
WHO WANTED IT CHANGED? Republicans in Congress opposed the rules, which applied to ceiling fans, heating and cooling appliances and other devices, as well as residential buildings owned by the federal government, saying that they would place an unfair cost on consumers.
WHO WANTED IT CHANGED? The trucking industry supported the changes for bridge and pavement condition guidelines, but strongly opposed measures aimed at environmental sustainability and mitigating climate change.
WHO WANTED IT CHANGED? Coal companies, along with Republican officials in several states, sued the government over this rule, which regulated the amount of mercury and other toxic pollutants that fossil fuel-fired power plants can emit into the air. They argued that the rule helped shutter coal plants, many of which are already compliant. Oral arguments in the case have been delayed while the E.P.A. reviews the rule.
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