— -- Ten students, working for ABC News, visited nuclear reactors on 25 college campuses and found many gaping security holes at many of them, prompting a federal investigation. Here's what the team found at MIT.

Reactor Name: MIT Nuclear Reactor Laboratory

Fuel: Highly-enriched uranium, possession limit 40 kg.

Power Level: 5 MW

Began Operating: 1958

Location: In a highly populated area just off Massachusetts Avenue, the heavily traveled main artery that runs through Cambridge. The dense area includes campus buildings, pharmaceutical laboratories, shops and restaurants.

Security Obervations: Two armed guards. No metal detectors. No searches. Tour available with advance request and interview. Multiple forms of identification requested and photocopied before tour. Backpacks allowed inside the complex, though not inside the reactor building. Wallets permitted on reactor tour.

What We Found: Detailed information (including labeled diagrams and photographs of the reactor core and its full operation schedule) was easily located on the Internet. Even more information was available using campus computer terminals available to the public at the MIT library, where the Fellows found detailed floor plans of the reactor.

The Fellows scheduled a tour by e-mail and, after a brief interview with a few staff members, toured the reactor.

An ABC News producer parked a large Ryder truck next to the reactor facility and was not questioned or challenged.

University Reaction: In a written statement, Denise Brehm, senior communications officer, said given the small size of the reactor facility, it is not a likely target for terrorism.

Brehm said an independent study assessing the impact of possible terrorist acts against the reactor concluded that in all likely scenarios the core of the reactor would not be breached and radiation would not be released. According to Brehm, the study also determined that a large truck bomb within even a few feet of the reactor building would not breach the containment of the reactor's core. The core is fully enclosed in a radiation-shielded structure consisting of several feet of concrete and other materials, which itself is housed within the containment building, "all of which would impossible to breach at one time," Brehm said.

Tours are by appointment only and names, addresses and identification are run through a security review prior to the tour, Brehm said, adding that visitors are not allowed to bring bags or cameras into the reactor building, but must leave them in the administrative offices.

"MIT moved its reactor floor plans and exterior diagrams from its Web site following the 9/11 terrorist attacks," according to Brehm. Posting of the operating schedule does not pose a security threat because it does not indicate "when MIT is conducting sensitive operations, such as a refueling."

"Fresh fuel is not stored in the facility and is never present in large enough quantities to create a nuclear weapon," Brehm said.

Additional Comment: The federal official responsible for security at the nation's campus reactors told ABC News that he was not happy to see the wide availability of detailed information on the Internet. "That's something I'd want us to pursue, and we will," said Roy Zimmerman, director of the Office of Nuclear Security and Incident Response for the Nuclear Regulatory Commission.

Zimmerman said he is aware of the studies cited by MIT that concluded the reactor core could survive a close-range truck bomb. Nonetheless, he considered ABC News' investigation valuable. "It's something that I think is worthy of follow-up," Zimmerman said, "If the security plans are not being met, or in hindsight, there is an additional measure that should be in place that's not currently there, we want to be able to look at that."

Veteran security consultant Ronald E. Timm has analyzed the vulnerability of the nation's nuclear laboratories for the Department of Energy. He said that the presence of two armed guards at MIT is "a very good start for where you want to go."

But Timm was critical of other elements of MIT's security.

Timm said that in just 60 seconds a terrorist could cut a hole big enough for a truck loaded with explosives to drive through. As for the detailed information still available on the Internet, despite MIT's claim that it was removed after 9/11, Timm said the floor plans and diagrams would be a big help to a potential terrorist planning an attack: "This is what the bad guy is looking for."

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