Jeff Alson was sitting in his apartment in Ann Arbor, Mich., when he felt like he was going to explode. 

The retired environmental engineer, who worked at the Environmental Protection Agency for 40 years, had just read a letter written by one of his old bosses, agency chief Andrew Wheeler. 

In it, Wheeler told Congress that EPA career experts had not been cut out of the process of crafting one of the Trump administration’s most controversial environmental proposals to date — one that would abandon one of President Barack Obama’s signature climate policies.

Alson was one of those EPA experts before retiring in April 2018. He was fuming, he later said, because he believed what Wheeler was saying was wrong.

“I gave myself five minutes,” the 63-year-old retiree said in an interview Friday. “I sat there and tried to calm down. But I said, ‘You know what? Enough is enough.’ “

Alson is speaking out at a moment of rising tension between Trump officials and California regulators as the federal government prepares to freeze in place pollution rules for new cars and light trucks for the next six years — rather than ratchet them up to rein in carbon emissions as the Obama administration wanted to do.

Wheeler and Mary Nichols, chairwoman of the California Air Resources Board, spent Thursday trading barbs after failed negotiations to allow California to keep its waiver allowing the state to set its own rules under the Clean Air Act, a practice the federal government has sanctioned for decades.

In prepared testimony, Nichols told lawmakers on the House Energy and Commerce Committee that in more than a dozen meetings with federal officials, “the Trump Administration has been unwilling to find a way” toward a resolution between with California.

She also said that “U.S. EPA’s professional staff and California’s engineers were cut out of this proposal’s development.” 

Responding in his own letter to lawmakers, Wheeler said Nichols never offered a counterproposal and accused Nichols of not being “a good faith actor in this rulemaking.” He added that “[h]er testimony that EPA professional staff were cut out of this proposal’s development is false.”

It was that last statement that got Alson’s blood boiling.

“I can speak from direct experience that Mary Nichols is telling the truth and Administrator Wheeler is lying,” he said.

According to Alson, under previous administrations technical staff at the EPA and the National Highway Traffic Safety Administration, part of the Transportation Department, would spend hours ironing out details of how fuel-efficiency standards should work before the agencies jointly rolled out the tailpipe rules for new cars.

But Alson said before the Trump administration’s proposal was rolled out, there were no such technical meetings between the technical staffs of NHTSA and the National Vehicle and Fuel Emissions Laboratory, the EPA’s state-of-the-art facility in Michigan where investigators helped uncover the Volkswagen emissions scandal and where Alson worked for decades. 

Instead, he said, there were only a few what he calls “check-the-box” meetings between the agencies in early 2018. 

“NHTSA was unwilling to tell EPA what they were doing,” Alson said. “At the end of the day, they completely controlled every piece of analysis.”

During a joint hearing of two House Energy and Commerce subcommittees Thursday, Democrats grilled the EPA’s air policy chief, Bill Wehrum, about his office’s involvement in the proposal. 

“Was it accurate that they had little involvement in the process?” said Rep. Paul Tonko (D-N.Y.), referring to the Office of Air and Radiation.

“Through the course of this rulemaking, EPA has had a substantial amount of involvement,” Wehrum responded.

EPA spokesman Michael Abboud reiterated the points made in Wheeler’s letter. “The letter speaks for itself,” Abboud said. “Career, professional staff within the Office of Air and Radiation were involved in the development of the proposal and continue to be involved in the final stages as we work with NHTSA to finalize this rule.”

But documents released in the rulemaking process last year show bitter disagreement between the two agencies over the logic of the move.

The Transportation Department agency said that upping car mileage per gallon make new cars more expensive and lead to consumers putting off purchases. That, in turn, would mean more older cars on the road that would not perform well in accidents and more auto fatalities.

An internal EPA analysis at the time, however, found that not going through with the Obama-era rules would lead to slightly more fatalities. At one point, the disagreement became so pronounced that an EPA staffer asked for the agency’s name and logo to be removed from a key regulatory report.

California and other states have vowed to challenge the freezing of the fuel-efficiency standards in court once they are finalized. If the EPA’s technical staff were cut out of the process, as Alson contends, that may provide fodder for a lawsuit.

“The Clean Air Act requires EPA to be ‘the decider’ for its own rules, so IF it could be clearly shown in the record that EPA relinquished decision-making authority to NHTSA, that could be a problem for EPA in the courts,” Jody Freeman, director of Harvard Law School’s Environmental and Energy Law Program, wrote by email.

Alson said he is going public now because most of his former colleagues still work at the agency and can’t “set the record straight” without fear of reprimand.

“I felt a responsibility to do that because I’m the only person who could stand up and do that,” he said. “Everybody else who still works there can’t say that.”