United States Nuclear Regulatory Commission - Protecting People and the Environment


NRC Seal NRC NEWS

U. S. NUCLEAR REGULATORY COMMISSION

OFFICE OF PUBLIC AFFAIRS, REGION I

475 Allendale Road, King of Prussia, Pa. 19406

CONTACT: Diane Screnci (610)337-5330/ e-mail: dps@nrc.gov
Neil A. Sheehan (610)337-5331/e-mail: nas@nrc.gov

I-97-52

May 12, 1997

NRC PROPOSES $650,000 CIVIL PENALTY FOR NORTHEAST UTILITIES

FOR ALLEGED VIOLATIONS AT HADDAM NECK NUCLEAR POWER PLANT

The Nuclear Regulatory Commission staff has proposed a $650,000 fine against Northeast Utilities for more than 70 alleged violations of agency requirements at the company's Haddam Neck nuclear power plant in Haddam, Conn.

Most of the violations cited by the NRC pertain to numerous longstanding deficiencies in engineering programs and practices, as well as errors related to an event involving a nitrogen buildup in the reactor vessel last year. The agency also found a number of lesser violations, including emergency planning flaws, for which no fines have been proposed.

While none of these matters immediately threatened public safety, NRC Region I Administrator Hubert J. Miller wrote in a letter to Northeast Utilities that the violations and underlying causes demonstrated "significant departures from the defense-in-depth principles upon which nuclear power plants are designed, built and operated, and upon which the NRC relies to ensure nuclear power plant operation does not jeopardize public health and safety."

Mr. Miller added: "Many of the violations should have been identified and corrected sooner. In other cases, corrective action was not taken after the violations were identified. Many of the violations were caused by a lack of questioning attitude by your staff. Also, managers should have conveyed high safety standards to the staff to seek, find, evaluate and correct problems. This did not occur."

The violations were identified during NRC inspections conducted between November 1995 and November 1996. Most were discussed with the utility at a predecisional enforcement conference last December 4. Despite the utility's decision late last year to shut down the plant permanently, Mr. Miller said the fines were necessary to stress: 1) the high regulatory significance the NRC attaches to these violations; 2) the need for effective management and oversight during the plant's decommissioning, as well as effective management and oversight at the utility's Millstone and Seabrook facilities; and 3) the need for other reactor licensees to have effective oversight of their nuclear power plants.

NRC's formal Notice of Violation groups the civil penalty violations into two broad categories: one citing multiple examples of engineering errors, the other the incident last year in which nitrogen gas leaked into the reactor vessel, resulting in a reduction in reactor water level.

Multiple examples of engineering errors.

NRC found that Northeast Utilities failed to ensure the plant was maintained as designed and specified in its Updated Final Safety Analysis Report (UFSAR), which is essentially the plant's operational blueprint. Inspectors further determined that inadequate engineering evaluations caused additional design mistakes during design changes; that design changes were made to the plant without adequate safety evaluations; that adverse conditions were neither identified nor corrected; and that the UFSAR was not updated as required.

Inspectors also found that safety margins were reduced, and in some cases technical specifications were violated, as a result of poor engineering. For example, too small pipes leading from the containment sump system to the residual heat removal pump left insufficient suction to support pump operation without relying on containment building backpressure. This violation is significant because it could have caused a failure of the system needed to keep the reactor core cool in the event of an accident.

Another example was the failure to begin repair work on the low-pressure safety injection system, even though a design deficiency was discussed during a February 1996 predecisional enforcement conference. At the time of a special team inspection in April 1996, the project, involving 19 recommended corrective action items, had not yet been assigned to anyone, despite a commitment Haddam Neck made to undertake repairs. Also, larger than allowable holes were found in the screen mesh of the containment sump, which would be used to provide emergency cooling water in the event of a loss-of-coolant accident. The oversized mesh and an area lacking screening could have allowed debris to get into the pump during an accident and render emergency core cooling system components inoperable.

Lastly, on July 22, 1996, operators had to shut down the plant when it was determined the containment air recirculation system was inoperable.

In many of the cases, applicable regulatory requirements and design bases were not correctly translated into specifications, drawings, procedures and instructions. Formal design calculations and analyses were, at times, based on incorrect assumptions and were not sufficient to confirm the systems would work as intended; calculations frequently lacked technical rigor, thoroughness and attention to detail; engineering supervisors, independent design reviewers and oversight committees generally failed to identify and/or correct the problems; and management's responses to self-assessments, quality assurance audits and third-party reviews were inadequate.

A fine of $350,000 has been proposed for these violations.

Nitrogen leak into the reactor vessel.

For roughly four days, from late August 1996 through early September 1996, control room operators at Haddam Neck were unaware nitrogen gas was leaking from a valve into the reactor vessel, causing the level of water on top of the reactor core to decrease to about 3 feet below the vessel's flange. Even after plant managers became aware of the problem, they were slow to appreciate the significance and respond effectively, according to an NRC augmented inspection team review of the event. A further drop in water level could have challenged the functioning of the plant's decay heat removal system, which is needed to keep the fuel in the core cool while the reactor is shut down.

The inspection team determined that several operational procedures were inadequate; and that plant operators did not follow plant procedures, did not exhibit a questioning attitude as the nitrogen accumulated in the reactor vessel and made inappropriate decisions while draining the reactor on August 29 and opening a reactor coolant loop on September 1. It also found that senior operators did not convey expectations to less experienced field operators during pre-job briefings.

A $300,000 fine has been proposed for these violations.

The NRC has cited Northeast Utilities, but proposed no fines, for emergency preparedness weaknesses noted during an August 1996 exercise. Inspectors found that plant staff failed to recognize the need for an "alert declaration" early in the drill and later, following the declaration of a "general emergency," failed to implement appropriate protective actions for on-site personnel. They also failed to recommend protective actions for areas outside the 10-mile emergency planning zone, based on the dose projections during the exercise. Overstaffing of key site emergency response organization positions very early in the drill caused confusion and problems. Consequently, it was not possible to determine if the plan could be carried out with minimum staffing, as specified in the emergency response plan.

The overall civil penalty of $650,000 is the sixth largest ever proposed by the NRC.

The utility has 30 days to pay the proposed fine or to request in writing that all or part of the penalty be withdrawn.

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