Republican lawmakers are demanding the Environmental Protection Agency (EPA) inspector general’s office investigate alleged collusion between agency officials and lobbyists to undermine the Trump administration’s deregulatory agenda.

Four GOP lawmakers and the chair of a powerful House subcommittee want to know why EPA officials worked with trucking lobbyists on a study that was never approved by administration officials, yet obtained and touted by opponents of repealing regulations on refurbished heavy-duty truck engines.

“When EPA Administrator Scott Pruitt repealed the current glider rule, career employees at the EPA communicated with the original equipment manufacturer (OEM) with the intent of eliminating the glider industry,” four GOP lawmakers, led by Rep. Bill Posey of Florida, wrote to EPA Inspector General Arthur Elkins.

“In our opinion, EPA’s conduct undermines the current Administration’s policies and prevents the repeal of the rule,” Republicans wrote to Elkins in a letter sent Thursday that was obtained by The Daily Caller News Foundation.

Separately, Rep. Greg Gianforte, chairman of a subcommittee on the House Committee on Oversight and Government Reform, sent a letter to Elkins demanding an investigation into whether collusion between EPA and Volvo lobbyists “violated any policies or procedures intended to ensure objectivity and integrity of tests conducted at” the National Vehicle and Fuel Emissions Laboratory (NVFEL) in Ann Arbor, Mich.

Glider kits are new truck bodies that use refurbished engines and are substantially cheaper to buy than trucks with new engines. Gliders also don’t have to comply with costlier emissions control regulations until the Obama administration began more heavily regulating them in 2016.

EPA Administrator Scott Pruitt’s plan to repeal glider kit regulations would get rid of quotas imposed on companies that have forced mass layoffs in the industry. Pruitt began the repeal effort last year after Fitzgerald, a leading glider maker, petitioned the agency. (RELATED: Environmentalists Are Pushing Misleading Info To Attack Scott Pruitt)

Gianforte wrote:

The letter comes after TheDCNF reported on emails obtained by former Trump transition team member Steve Milloy showing high-level officials at EPA’s vehicle testing lab were working with lobbyists with Volvo Group North America on a study that’s been used to undermine deregulating the glider industry.

“The emails show that Volvo lobbyists were working to supplying EPA staff with glider trucks so that rogue EPA staff could dishonestly ‘test’ glider emissions and issue a damning report that could be waved about at a public hearing on the proposed rule rollback,” Milloy said.

Volvo opposes repealing regulations on glider kits. Volvo and other truck engine makers joined environmentalists in lobbying the Obama administration to regulate glider kits in 2016, so their coordination with EPA on the study raises red flags for lawmakers.

EPA never officially released the study, but somehow Volvo lobbyist Susan Alt obtained a copy of the research findings, which she touted during a public hearing last year on EPA’s plan to repeal glider kit regulations.

Gianforte also said lawmakers “obtained information that shows a small number of employees orchestrated this testing and submitted the test results to the public rulemaking docket without the knowledge or approval of EPA leadership.”

Moreover, Posey’s letter claims EPA employees may have deleted communications with Volvo lobbyists and other opponents of glider trucks.

“Even more troubling, there is a strong possibility that email communications between EPA and the OEM may have been deleted,” reads Posey’s letter.

“We ask that you use your authority to investigate this potential violation and seize all computer hardware and related software as outlined in the attachments for a deeper forensic investigation into the missing emails,” Posey and colleagues wrote to Elkins.

Read Posey’s letter here.

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