BALTIMORE (Map, News) - Federal investigators have returned to Peach Bottom Atomic Power Station to evaluate security lapses after an investigation found guards had been sleeping on the job.

Nuclear Regulatory Commission investigators arrived Monday to conduct a follow-up inspection after whistle-blower Kerry Beal secretly taped his fellow guards dozing on the job over the summer.

Security company Wackenhut lost its contract to guard the Exelon Corp.-operated plant Nov. 1, and Beal lost his job during the investigation.

“Essentially, this will determine if there are performance issues to be addressed, and if Exelon is addressing the root causes they’ve identified,” said Diane Screnci, an NRC spokeswoman.

The initial NRC probe in September found guards believed it acceptable to sleep in the “ready room” near the reactor at the plant, about six miles over the Harford County line in Pennsylvania.

The probe also revealed the ready room did not provide enough activity for guards to keep them alert; guards could not be observed or inspected unannounced; management did not effectively convey that sleeping was unacceptable; and supervisors did not pass along or address complaints about the sleeping guards.

NRC investigators will likely interview plant employees to see whether they now feel comfortable reporting problems to their supervisors, Screnci said.

Samuel Collins, NRC’s administrator for the region including Peach Bottom, said the four-person inspection team would follow up on the initial fact-finding mission and ensure that the problems it identified were being addressed.

“Let me emphasize again that we have zero tolerance for inattentiveness on the part of any nuclear power plant security officer,” Collins said.

As part of its response, Exelon posted a supervisor in the ready room at all times, though Beal told The Examiner on Monday that the guards often joked about other places to sleep on-site.

Despite the follow-ups, the watchdog group Project for Government Oversight was not confident that the investigation could produce a real change in attitude about reporting problems, especially after Beal lost his job in the transition between Wackenhut security and an in-house Exelon force, which includes some guards from the former Wackenhut team.

“It would take a whale of a change — supervisors getting fired for not reporting what they knew, people above them getting whacked,” said Peter Stockton, an investigator for POGO. “It will take a whole lot to build enough confidence so people will feel like they can come forward.”

msantoni@baltimoreexaminer.com