Dominion Energy to replace North Anna reactor vessel head this fall

RICHMOND, Va., Oct. 9, 2002 — Dominion Energy, the electric generating unit of Dominion, announced Monday it will purchase a new, crack-resistant vessel head from a French company and use it to replace the one at North Anna Power Station Unit 2 this fall. The company will install the new head in December.

The replacement will have no impact on Dominion’s 2002 or 2003 earnings.

The pressurized water reactors used by Dominion Energy and Electricite de France (EDF), the French energy company, are of virtually identical design. EDF has a spare vessel head in storage.

Dominion considered repairing the unit until it realized that repairs would take about as much time as replacing the vessel head.

Thos. E. Capps, chairman, president and chief executive officer, said:

“It makes economic sense for us to buy this spare vessel head from EDF and replace it now rather than continue making repairs to the existing one. We could perform the repairs and safely return the unit to service for another 18 months and then replace it, as we had originally planned, but the availability of the EDF spare changed our plans.”

During a 2001 inspection, operators found problems and decided to replace the reactor vessel heads for Dominion’s four nuclear reactors in Virginia.

The replacements will resolve degradation issues associated with penetrations, or tubes, on the vessel heads. The tubes guide control rods in and out of the uranium fuel core, absorbing neutrons and controlling the fission inside the reactor. The reactor head is more than 6 inches thick carbon steel with a quarter-inch stainless steel liner.

Dominion inspected the North Anna and Surry reactor heads in 2001 after several companies found heads damaged by acidic water that was seeping from inside the reactor around the control rod tubes.

The water, which contains boric acid to supplement control of the fission process, cools the uranium fuel. The industry identified all pressurized water reactors as having the potential for this problem and the U.S. Nuclear Regulatory Commission ordered inspections.

The company identified nine penetrations with apparent seepage or that did not meet American Society of Mechanical Engineers code on two of the four reactor heads — six indications on Surry Unit 1 and three on North Anna Unit 2 — and made repairs. There were no indications of damage on the North Anna Unit 1 or Surry Unit 2 reactor heads.

Dominion’s inspection and analysis of the North Anna Unit 2 vessel head penetrations will not alter the operating or refueling schedules of the company’s three other Virginia nuclear units. The company still intends to replace the vessel heads on North Anna Unit 1 and Surry Units 1 and 2 during scheduled refueling outages by the spring of 2005, as announced last month. The replacement costs are already included in Dominion’s future earnings projections.

Dominion is one of the nation’s largest producers of energy, with a production capability of more than 3 trillion British thermal unit of energy per day. Dominion serves nearly 3.8 million franchise natural gas and electric customers in five states. For more information about Dominion, visit the company’s Web site at .

Source: Dominion Energy

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