In a long-expected move, President Donald Trump formally nominated acting U.S. Environmental Protection Agency (EPA) head and former coal lobbyist Andrew Wheeler to officially run the agency Wednesday.

Wheeler has headed the EPA for six months following the resignation of disgraced former Administrator Scott Pruitt, making him the longest-serving acting administrator in EPA history, The Huffington Post reported. His nomination is expected to clear the Republican-controlled Senate.

"I am honored and grateful that President Trump has nominated me to lead the Environmental Protection Agency," Wheeler said in a statement reported by The Huffington Post. "For me, there is no greater responsibility than protecting human health and the environment, and I look forward to carrying out this essential task on behalf of the American public."

However, many environmental groups disagreed with his self-assessment and raised concerns about his existing record on protecting environmental and public health and fighting climate change.

"The only thing Wheeler is going to protect at the EPA is the profits of polluters," Center for Biological Diversity Government Affairs Director Brett Hartl said in a statement. "I'm sure corporate board rooms will celebrate this nomination. But for anyone who drinks water, breathes air or cares about wildlife, this will be nothing but awful."

Here are some of Wheeler's most controversial decisions as acting-administrator, as cited by the Center for Biological Diversity and other environmental groups.

1. In August, he released a proposal rolling back Obama-era vehicle emissions standards and revoking California's waiver under the Clean Air Act to set its own.

2. Also in August, he unveiled a replacement for former President Barack Obama's Clean Power Plan that would increase greenhouse gas emissions and cost more than a thousand lives a year, according to the EPA's own calculations.

3. In December, Wheeler released an attack on the Obama-Era Waters of the U.S. rule that would deny protections to streams that only flow if it rains and wetlands not connected to larger waterways.

4. Also in December, Wheeler offered a major boon to the coal industry, rolling back another Obama-era rule meant to limit the emissions of Mercury and other toxins from coal-fired plants, the Environmental Defense Fund (EDF) pointed out.

Wheeler earned the dubious honor of being only the second nominee for EPA head that the EDF has ever opposed. Pruitt was the first.

"We evaluate executive appointments with the presumption that every President has a right to name his team unless a nominee would threaten the health and safety of the American people. Unfortunately, Andrew Wheeler's record puts him in that category," EDF President Fred Krupp said in a statement.

Wheeler worked for the EPA in the 1990s before joining the staff of Oklahoma Senator and climate denier James Inhofe. He then moved to the private sector, where he lobbied for Murray Energy Corp, the nation's most prominent underground mining company, CNBC reported. Wheeler has said he is "not at all ashamed" of his work for Murray.

Wyoming Republican Senator John Barrasso, who chairs the Environment and Public Works Committee responsible for taking the initial vote on Wheeler's nomination, said he was excited to get Wheeler appointed.

"Acting Administrator Wheeler has done an outstanding job leading EPA and is well qualified to run the agency on a permanent basis. I will work with committee members to get him confirmed," he said in a statement reported by The Hill.

The committee announced plans Wednesday to hold a hearing Jan. 16, despite the fact that the EPA is still in shutdown mode, Bloomberg Environment reported. The decision to hold the hearing despite the shutdown was criticized by Democrats and environmental groups.

"There is no clearer statement of the priorities of Donald Trump and Senate Republican leadership than their abdication of their duty to keep the public safe and the government running while ramming through a toxic nominee like coal lobbyist Andrew Wheeler during a government shutdown," Sierra Club Legislative Director Melinda Pierce said in a statement. "This is an insult to every EPA employee and federal contractor who has been furloughed or forced to go without a paycheck during this shutdown and a threat to the public that deserves clean air and clean water. Senate Republicans confirming Andrew Wheeler to lead the EPA is the equivalent of leaving the EPA shut down, because he will do nothing to protect the health of the public and everything to enrich corporate polluters."