Waterford – The U.S. Nuclear Regulatory Commission is investigating what it termed issues of “greater than very low” security significance discovered at the Millstone nuclear power station during a Sept. 28 inspection.

NRC officials declined to specify the nature of the security issue or define its significance but said the problems were “corrected or compensated for” before inspectors left the complex that day, according to a letter sent Tuesday to David Heacock, president and chief nuclear officer at Dominion Resources.

“The finding is also an apparent violation of NRC requirements and is therefore being considered for escalated enforcement action in accordance with the NRC’s Enforcement Policy,” the letter, signed by Darrell J. Roberts, NRC director of reactor safety, stated.

The inspectors’ report defining the problems will remain confidential, Roberts wrote.

Dominion will have 30 days to respond to the inspection report. The response could include a request for a regulatory conference or a written response report. The company’s response also would be kept confidential, “because it involves sensitive security information,” Roberts wrote.

Dominion spokesman Ken Holt said the company received Roberts’ letter and the inspection report on Tuesday and has not yet responded. Holt said Dominion is evaluating what the company’s response would be. He said he could not discuss the nature of the safety issue involved in the report.