President Donald Trump has fired numerous Cabinet members, some for good reason, some for no particular reason at all.

There is a growing list of reasons why he should fire Scott Pruitt, head of the Environmental Protection Agency.

Pruitt’s outright hostility to environmental regulations and his deference to corporate polluters were reason enough for Trump not to hire him to oversee the department meant to safeguard America’s air, water and land.

Sen. Susan Collins was the only Republican in the Senate to raise concerns about Pruitt and to vote against his nomination. Her concerns were well placed then and they remain valid today as the depth of Pruitt’s mismanagement of the EPA becomes clear.

It is also becoming obvious that Pruitt believes ethics rules and standards don’t apply to him. It is time to put a stop to his imperial reign at the EPA and to end his squandering of taxpayer dollars.

“Let me say that the actions taken by Scott Pruitt in the environmental arena, whether it is trying to undermine the Clean Power Plan or weaken the restrictions on lead or undermine the methane rules, are reasons enough to validate my decision to oppose his confirmation,” Collins said earlier this month during an appearance on CNN’s “State of the Union.”

“This daily drip of accusations of excessive spending and ethical violations serve to further distract the agency from accomplishing its very important mission,” she added.

“I think Scott Pruitt is the wrong person to head the EPA,” she said later in the April 8 interview.

Two House committees are holding hearings on Pruitt on Thursday. Republicans senators are calling for Senate hearings as well.

There are a lot of questions that need to be answered. On the environmental front, Pruitt has overseen the rollback of restrictions on pollution, which puts human health at risk, and the withdrawal of the United States from an international agreement on climate change, all in the name of protecting and promoting U.S. businesses.

Penalties for violating environmental laws have been weakened. Just this week, the EPA announced a new policy to restrict the kind of science the agency uses to develop new policies. It would stop the use of research that relies on confidential health data. This data is confidential to protect the identity of the people who agree to participate in such studies.

On the ethical front, the list of improprieties seems to grow by the day. Pruitt installed a soundproof phone booth in his EPA office, at a cost of $43,000. Beyond the waste of money, it raises questions about who Pruitt is talking to and why does he want to keep his conversations secret.

Pruitt has demanded around the clock security and motorcades to dinner and airports. He routinely flies first class and on charter flights. He justifies this for security reasons, although he flies in coach when he has to pay for travel out of his own pocket.

When he began work at the EPA, Pruitt rented rooms in a townhouse in Washington, D.C., for $50 night, far below the cost of a hotel room or condo rental in the nation’s capital. The townhouse is owned by the wife of lobbyist with businesses before the EPA. The couple held a fundraiser for Pruitt in 2014, when he was Oklahoma’s attorney general.

Pruitt’s actions make a mockery of the notion of public service and are a huge distraction for the Trump administration and Congress when both need to be focused on pressing issues, such as America’s opioid crisis, rising health care costs, the war in Syria, and North Korea’s nuclear program.

It is time for him to go.

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