A recently constructed 10-foot high solid wooden wall runs the length of the property facing the highway. A private security force brought in from New York patrols the grounds 24/7 with holstered sidearms.

After commandeering the former rest area on Interstate 91 North in Hartford — with the state of Vermont’s blessing — the federal government is making it clear that the public needs to stay away. But since the front gate was open one afternoon last week, I couldn’t resist. With the feds treating the site like it’s Los Alamos, there had to be more happening behind the barrier wall than what government officials were letting on.

The official line: The Federal Emergency Management Agency is using the shuttered rest stop as a “staging yard.”

Trucks coming in from Alabama and Maryland are dropping off mobile homes that will eventually be used as temporary housing for Vermonters wiped out in the summer’s flash flooding.

I didn’t think FEMA would mind if I stopped by unannounced to check out the homes, which range from one to three bedrooms.

Boy, was I mistaken. The armed security guard, dressed in all black, blocking the entrance made it plain that FEMA wasn’t accepting visitors.

Standing in front of my car, he got on his portable radio. A few minutes later, reinforcements arrived.

“Do not get out of your vehicle. You need to leave immediately,” ordered a man (without a gun) who wouldn’t give me his name. “This is FEMA property.”

He did, however, give me a phone number for FEMA’s “external affairs” office.

After pestering FEMA flacks by phone and email for a couple of days, I was allowed to enter the compound on Wednesday. With an FEMA escort, of course.

The wall and armed guards?

“It’s about safety,” said my tour guide, Andre Bowser, a FEMA external affairs officer.

Without the wall, motorists might start “rubber-necking” into the former rest area instead of focusing on the road ahead, he said.

The wall and guards, employees of a Long Island, N.Y., company called Strategic Security, also serve as a deterrent, Bowser said. Without the security measures, would-be thieves could break into the mobile homes and cart off government property.

I can’t say for sure what furniture the temporary homes come with. FEMA wouldn’t allow me to step inside any of the 20 or so homes stashed behind the wall.

“Please understand clearly this location is an ACTIVE CONSTRUCTION SITE and, for safety reasons, you WILL NOT be able to enter the units,” Angelique Smythe, a FEMA spokeswoman emailed me before my tour.

Even without the all-caps, I got the message. But it was my first visit to a so-called construction site where workers didn’t wear hard hats. (Maybe OSHA rules don’t apply to FEMA.)

FEMA’s desire to keep the lid on its activities is less about safety and more about control.

Since the early 2000s, FEMA has been part of the Department of Homeland Security. It operates on a need-to-know basis. And the less the public knows about its business, the better.

But the obsession with secrecy works to FEMA’s detriment. The lack of transparency has led to rumors springing up on social media about what the federal government could actually be up to.

On the instant message board Reddit, someone posted, “They are saying it is for housing for the flood victims, but I have been told it is really for immigrants. Why would they build a guarded complex (at a former rest area) for flood victims and not in a nicer place. But being on the interstate makes it easy for bringing in immigrants.”

I can’t blame anyone who is familiar with the history of this stretch of I-91 for being suspicious after the feds suddenly appear on the scene.

In Post-9/11, the U.S. Border Patrol set up a roadblock for weeks at a time in the I-91 southbound lanes, across from where FEMA now has its base.

Drivers, including myself, were often stopped. Law-abiding motorists were required to tell armed federal agents where they were headed and why. For nonwhite drivers and their passengers, particularly those who spoke with the hint of a foreign accent, getting through the checkpoint could be time-consuming and nerve-racking.

Before my tour on Wednesday, I talked with Joe Flynn, Secretary of Vermont Agency of Transportation, about the rumors on social media. What’s going on behind the wall? I asked.

“It’s a totally fair question,” Flynn said. “But there’s nothing nefarious happening there. It’s for the benefit of Vermonters who are in dire need now.”

Many of the manufactured homes will likely end up in Montpelier, where a former country club now owned by the city could become a temporary mobile home park. Other “FEMA trailers” are destined for Lamoille and Windsor counties.

The rest area, which closed a dozen or so years ago, remains state property, but FEMA has taken over control for the time-being, rent-free, Flynn said.

FEMA is paying for security guards and the building of the 800-foot wall, which means it’s coming out of the pockets of federal taxpayers.

An argument could be made either way whether they’re worthwhile expenses.

Still, it would be nice to know how much FEMA’s operation at the former rest area is costing. With that in mind, I asked Bowser, the FEMA media relations specialist, if he could get me the cost of the wall.

He didn’t have the information, instead referring me to FEMA headquarters in Washington. I emailed and left a phone message at FEMA’s “national news desk.” I didn’t hear back last week.

It could have just been an oversight. Or maybe FEMA doesn’t want the public to know its wall was built with the Pentagon’s infamous $435 hammers.

Jim Kenyon can be reached at jkenyon@vnews.com.