The number of employees at the Environmental Protection Agency is shrinking.

A record number of EPA workers have been retiring in recent years and many of these employees are not being replaced. This is leaving behind demoralized employees with more work to do, and raising questions about whether the agency can continue to meet the demands of protecting the environment.

Some current and former employees are now speaking out. And they say it’s not just an issue of the agency’s headcount. They’re concerned about the rollback of federal rules and regulations, and they want to see an agency that’s empowered to protect the environment.

Ronnie Levin worked for the EPA for more than 37 years, most recently in the regional office in Boston as a lead housing inspector, risk assessor and senior scientist.

"I loved it,” Levin said. “I think the EPA is fabulous. It's a good thing to tell your kids that you do, your friends are happy for you. Everybody loves the environment."

But over time, she said, the agency changed.

"I would say my last very few years became intolerable," she said.

Levin retired from the EPA in 2017. She left an agency with a reduced number of employees, more work and damaged morale. Her experience is echoed by a number of veteran employees from Boston's EPA office who spoke with WGBH News.

"The fun was going out of the job," said Mary Beth Smuts, who retired two years ago after 27 years at the EPA.

"There was a feeling that there was purposelessness in some work, and that retirement would be more enjoyable than continuing to work there," said Bill Walsh Rogalski, who retired after 37 years.

"It's very demoralizing,” said Ann Rodney, who plans to retire this year. “There's a question, 'Why are we here? What is our mission?'"

"I don't think it's any secret to say that we feel like certainly we're in the crosshairs," said Margherita Pryor, who will hit 40 years at the agency this summer, and has no plans to retire.

The long tenure of these employees isn't unusual at the EPA. Nationally, more than 40 percent of the agency is reportedly eligible for retirement in the next five years. In the Boston office, there have been more than 60 retirements just since 2017, bringing the total number down to just over 500. And many of those positions aren't being replaced, which has resulted in shrinking the EPA agency-wide to its smallest size since 1987.

Levin said the agency is losing its most experienced people without passing on their knowledge.

"Nobody ever asked that I train a new person or that I hand over my files or anything,” she said. “I just walked out the door and closed it."

That’s because the EPA did not not hire a replacement for her.

“That’s the problem,” said Smuts, who had the same experience. “There was no one to pass it on to.”

Ann Rodney said when she leaves later this year, her work will be divvied up between three people.

“And so I feel badly that I'm leaving, because that just puts more work on other people,” she said. “But at the same time, it's time for me to go."

"And so, yes, people are picking up the slack,” said Pryor, who at 71 years old still has no plans to leave. “And so I personally work on, like, five different programs. And you try to do your best, and you hope that you're not letting anything big slip through the cracks, but it's just a huge amount of work."

It’s difficult to measure the direct impact of a reduced staff at EPA. But in its own data released last week, the agency reports that last year, it conducted roughly half as many inspections as it did in 2010, and the number of environmental crime cases opened was down by nearly two-thirds.

Some of the employees WGBH spoke with complained that the agency has gradually grown less creative and more bureaucratic in its problem solving over the decades. But they said things really took a turn for the EPA in 2016, after the election of Donald Trump.

The president’s proposed budget last year would have cut the agency’s funding by more than 30 percent. Congress never enacted those cuts, but the EPA is operating on temporary spending until the shutdown battle is resolved.

Pryor said that without an actual budget passed, for the rest of this year, some of the agency’s work is being held up.

“We don't know what we can give people,” she said. “We don't know whether we can issue a request for proposals. We don't know whether we can put money into a contract. I mean we do the planning for it. But until we actually get the okay on it, we're kind of in this limbo.”

Meanwhile, Bill Walsh Rogalski said one topic that's been essentially off-limits at the EPA in the Trump era is climate change.

"And then it just came down that you didn’t use the words ‘climate change,’ basically,” he said. “ You could talk about those kinds of contaminants only in the context where they were causing other environmental problems,” but not what was known to be their impact on the climate.

Rodney said they do talk about things like adaptation, "and we don't necessarily mention climate change,” she said. “But we are seeing that communities want to adapt to climate change. But we can't pull out the tool box and help them."

"It doesn't even make any sense. ... Why would you be against energy efficiency? Why do you not want to have light bulbs that don't use a lot of energy?" Pryor said. “ Why would you do this? Why would you deny that the cities are being flooded because of sea level rise? Why do you pretend like we don't know what's causing that?”

As she’s seen the staff shrink around her, Pryor worries that if the agency did try to hire new, younger people at this point, they wouldn’t want to work there.

"Why would you [work at the EPA] if you have other options? Who wants to put up with this?" she asked.

Those concerns are shared by Curt Spalding, who ran the EPA’s Boston office from 2009 to 2016, under President Obama. Spalding said that as he sees the depletion of ranks in his old office, he thinks back to what it was like to get calls for help from states and local communities here in New England.

"I'm afraid the regional administrator will have to say, 'No,' much more often when they are called to help — help a mayor, help a community, help a state solve a complex environmental problem,” he said. “And I'll tell you what is absolutely certain is the problem is growing and more complex."

Official spokespeople at EPA’s Boston office and Washington, D.C. headquarters didn’t provide a response when told what current and former employees are saying about people leaving the agency.