President Trump's nominee for deputy administrator of the Environmental Protection Agency, Andrew Wheeler, has spent much of his career working for less oversight from the agency.

A longtime aide to Sen. James Inhofe, known for his climate-denying antics on the floor of the Senate, Wheeler worked on environmental legislation for more than 15 years in various roles on the Senate Committee on Environment and Public Works. He helped to defeat a 2008 climate bill before leaving to be a private consultant and lobbyist.

That experience will serve Wheeler well as deputy administrator, his supporters argue, as the EPA continues to roll back Obama-era rules and regulations, and the agency works more closely with industry.

"I know where the laws are drafted," Wheeler said when he appeared before that same committee for his confirmation hearing last year. He joked with Senators and seemed at-ease answering questions from his old colleagues, even as Democrats raised concerns about his past work as a lobbyist.

Since 2009, Wheeler has represented the interests of some of the largest fossil fuel companies in the U.S. as a consultant and lobbyist , and national environmental groups including the Natural Resources Defense Council and Sierra Club oppose his nomination. According to an analysis of public documents by ProPublica , Wheeler has worked as a registered lobbyist for, among others, a major uranium mining company, one of the largest coal companies in the country and a refrigerant manufacturer.

Each of the companies has worked to shape EPA regulations in their favor in recent years.

The uranium mining company, Energy Fuels Resources Inc., is based in Colorado. Last year, the company lobbied to shrink Bears Ears National Monument, which is adjacent to one of the company's uranium processing mills. The refrigerant manufacturer, ICOR International , hired Wheeler to lobby Congress and the EPA for less stringent ozone regulations.

Following his nomination last fall, the Sierra Club's legislative director Melinda Pierce said Wheeler is "unfit for the job as Deputy EPA Administrator, given his obvious conflicts of interest working for the coal industry."

Wheeler also lobbied on behalf of utility giant Xcel Energy and has lobbied or consulted for multiple companies with interests in expanding the market for ethanol, including Growth Energy, the trade group for ethanol producers. The EPA is responsible for setting fuel requirements that affect the market for ethanol.

Xcel also has a complex relationship with the EPA. The company has invested heavily in renewable energy since the agency passed a sweeping electricity regulation which led states and utilities to make long-term plans for transitioning to clean energy. The EPA is now moving to repeal the so-called Clean Power Plan, but many states have still require utilities, including Xcel, to follow through on transitioning from dirtier fuels like coal to cleaner ones like wind, as the public radio collaboration InsideEnergy has reported .

Asked to comment on how Wheeler's past lobbying and consulting work might affect his approach to helping run the EPA, EPA spokesperson Liz Bowman said "Mr. Wheeler – like all political nominees – is committed to following the ethics advice of career officials at EPA and will recuse himself as needed, based on the advice of those experts."

The Senate panel's top-ranking Democrat, Sen. Tom Carper, said earlier this year that he had asked Wheeler specifically about his work with the coal company Murray Energy. The company's CEO Bob Murray has long fought environmental and climate regulations. Last year, Murray sent a memo to Pruitt laying out an "action plan" that included repealing limits on mercury emissions and reversing the agency's so-called endangerment finding that greenhouse gas emissions are dangerous to public health.

Murray also pushed for the administration to withdraw the U.S. from the Paris Climate Agreement, which President Trump announced he would do last year.

Speaking at a hearing, Carper said he had spoken to Wheeler about his relationship with Murray, and found Wheeler's explanations encouraging:

"I have met personally with Mr. Wheeler twice, and I have asked him directly whether he was involved in writing Mr. Murray's proposal. He assured me he was not. He told me that one of Murray Energy's priority issues he worked on was securing health and other benefits for retired miners. Moreover, he also assured me that he views EPA's legal authority to regulate greenhouse gas emissions, which is based on the 'endangerment finding,' as settled law. I have no reason to doubt Mr. Wheeler's assurances that at least on the question of the endangerment finding, he holds a view that is distinct from Bob Murray's."

Asked if Wheeler shared Murray's support for items in the action plan, Bowman said "Mr. Wheeler supports the president's decision to withdraw from the Paris agreement."

Wheeler has worked at the EPA before, as a special assistant in the agency's Office of Pollution Prevention and Toxics in the early 1990s. His focus was on regulating toxic chemicals — at the time, the EPA was working to update the agency's "early warning" system for keeping track of new chemical hazards.

Wheeler helped draft guidelines about what information chemical companies were required to disclose to the EPA.

That work may prove to be relevant to running today's EPA. More than 20 years later, the agency is in the midst of implementing a sweeping law passed under the Obama administration that changes many chemical reporting requirements. How that law is implemented will determine the EPA's power to enforce chemical pollution limits for the foreseeable future.

For example, the Trump administration rewrote and Obama-era proposed rule to narrow the number of chemicals the agency will review for safety hazards, excluding chemicals like flame retardants that are present in a lot of plush furniture, but are no longer used in manufacturing new products.

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