Palo Verde plant west of Phoenix was rapped in 2006
PHOENIX – The nation’s largest nuclear power plant has made “substantial improvements” since numerous performance deficiencies prompted a safety downgrade in 2006, according to a letter released Tuesday by the U.S. Nuclear Regulatory Commission.
The Palo Verde Nuclear Generating Station 50 miles west of Phoenix has been under scrutiny following a series of problems beginning in 2004 and culminating two years later with the safety downgrade. The move gave the plant the lowest rating of any of the nation’s more than 100 licensed reactors.
While the commission said the plant was being operated safely, its problem areas included safety-system reliability, human performance, and problem identification and resolution, among others.
The lowered safety rating triggered more stringent oversight by regulators.
“As a result of the problems they had, they were receiving the highest level of NRC oversight involving some 1,500 hours of inspection,” commission spokesman Victor Dricks said on Tuesday.
A March 4 letter released to the public Tuesday is the first indication that Palo Verde has improved its performance.
The commission wrote that Palo Verde has made “significant progress” in the letter to Randy Edington, executive vice president and chief nuclear officer of plant operator Arizona Public Service Co.
Of 12 areas in which the commission said that Palo Verde needed to improve, five have been resolved, the letter said. Those included long-standing equipment concerns, changes in management and other areas.
The findings of the remaining seven concerns, including problems with human performance, engineering programs, and emergency preparedness, will be released at a public meeting Tuesday.
“This is good news,” Edington said Tuesday. “It’s showing good momentum and good direction. We’ve made some excellent gains, but we’re also focused on how we can continue to get better from here.”
Edington said the improvements have come ahead of schedule; he had hoped to have them by the end of this year. “We’re basically ahead of the plan,” he said.
The problem that prompted the safety downgrade was an emergency backup generator that was inoperative for 18 days and unreliable for 40 days in 2006.
That problem came months after inspectors discovered that heat exchangers that cool emergency equipment and spent fuel storage areas at the triple-reactor plant had been fouled by years of plant technicians using an improper chemical mix. And in 2004, NRC inspectors found that APS had drained a large pipe designed to flood the reactors with water in an emergency years earlier without informing them.
Palo Verde supplies electricity to about 4 million customers in Arizona, New Mexico, Texas and California. It is run by APS for a consortium of power companies in the four states.
During the public meeting at 6:30 p.m. in Tonopah near Palo Verde, the commission staff will meet with APS representatives to discuss the plant’s safety performance during 2008. Commission staff members also will field questions from the public.
On the Web
Nuclear Regulatory Commission: www.nrc.gov
Arizona Public Service: www.aps.com
Palo Verde facts
Facts on the Palo Verde Nuclear Generating Station, the nation’s largest nuclear plant complex:
• Location: Wintersburg, Ariz., about 50 miles west of downtown Phoenix.
• Design: Uranium-fueled, steam-electric nuclear plant using a pressurized water reactor.
• Capacity: 3,739 megawatts from three 1,270-MW units. Provides enough power for approximately 4 million homes.
• Construction: Began in 1976, first unit online in 1986. Third and final unit running in 1988.
• Cost: $5.9 billion for construction and startup testing.
• Owners: Arizona Public Service, Salt River Project (Arizona), El Paso Electric Co., Southern California Edison, Public Service Co. of New Mexico, Southern California Public Power Authority and Los Angeles Department of Water & Power.
Source: Salt River Project