Waterford - Federal Nuclear Regulatory Commission inspectors discovered a security issue at the Millstone nuclear power station that was preliminarily determined to be of "greater than very low" security significance 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 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," stated the letter, which was signed by Darrell J. Roberts, NRC director of reactor safety.

Although the letter, which is vague on the nature of the problem, was made public, 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, which received Roberts' letter and the inspection report Tuesday, has not yet responded. Holt said he could not discuss the nature of the safety issue involved in the report.

Neil Sheehan, spokesman for the NRC Region 1, which includes Connecticut, said the federal agency has placed an emphasis on security since the Sept. 11, 2001, terrorist attacks. Some regulations took several years to implement, but he said they have been in place for "quite some time." Regular inspections ensure that they are being followed.

He said inspectors have discovered security issues above the very low significance level at other plants in the Northeast this year.

According to Roberts' letter, inspectors were at the Millstone complex on Sept. 28 for a "security baseline inspection" at Millstone Units 2 and 3. The inspection included an examination of security activities in compliance with NRC regulations and Dominion's license, a review of records and interviews with station personnel.

Although the issues discovered were corrected, NRC officials will continue to investigate the cause of the problem and whether further NRC action might be needed. At this point, the NRC did not issue a notice of violation to Dominion, and the federal agency intends to complete its report within 90 days of the Nov. 9 letter.

In addition to those security issues, two issues of "very low security significance" were revealed by Dominion staff and included in the inspection report. Dominion also has 30 days to respond to those issues, but the NRC considers them to be "non-cited" violations, because of the low significance.

c.bessette@theday.com