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Story highlights

Robert Kavlock also serves as acting assistant administrator for the Office of Research and Development

Kavlock has more than 33 years of scientific experience

(CNN) —  

The Environmental Protection Agency’s acting science adviser is retiring, he told CNN Saturday.

Robert Kavlock, who also serves as acting assistant administrator for the Office of Research and Development, will be leaving his position effective November 3, he said. He initially declined to explain the reasons behind his retirement, but in a follow-up email to CNN, he said he had worked at the agency for four decades “so it was not an early retirement.” He added that “the time was right to go for a variety of reasons.”

Kavlock, who has more than 33 years of scientific experience, previously directed the National Center for Computational Toxicology within ORD. He joined the EPA in 1977, according to his biography on the agency’s website.

The EPA did not immediately return requests for comment about Kavlock’s retirement or who will replace him in both of his roles.

President Donald Trump has made no secret of his desire to roll back environmental regulations and change the playing field for the fossil-fuel industry.

In May, EPA dismissed half the scientists who were serving on the executive committee of a key EPA science review board that provided guidance on air and water quality. An EPA spokesman told CNN at the time there were a total of 18 positions on the board and nine of those scientists were not renewed following the end of their three-year terms.

The next month, Kavlock was responsible for sending out emails to an additional 38 EPA science advisory board members alerting them that their terms would not be renewed, the advisory board’s executive committee chairwoman, Deborah Swackhamer, told E&E News. It was one of a number of moves EPA Administrator Scott Pruitt has made since taking the post to overhaul the agency’s scientific review process.

At the time, Kavlock wrote in a memo to the board members that was obtained by E&E News, EPA administrators wanted to reshape the committee.

E&E reported that he added later: “We are hopeful that an updated (Board of Scientific Counselors Executive Committee) and the five subcommittees can resume their work in 2018 and continue providing ORD with thoughtful recommendations and comments.”

This story has been updated with Kavlock’s follow-up comments.

CNN’s Rene Marsh contributed to this report.