Operators of the nation's largest nuclear power plant told Arizona utility regulators Tuesday the triple-reactor plant near Phoenix is safe and chances are remote that it could undergo a nuclear catastrophe such as the one in Japan.
The Arizona Corporation Commission requested a special open hearing with officials from Arizona Public Service, the state's largest utility company, which runs the Palo Verde Nuclear Generating Station for a consortium of power companies.
The plant is located in Wintersburg, about 50 miles west of downtown Phoenix, and supplies electricity to about 4 million customers in Arizona, New Mexico, Texas and California.
"I know APS is committed to safety," commissioner Paul Newman said. "But there are some hard questions we have to ask now and in the future. There's lots of population increase in a 10-mile and 25-mile area of Palo Verde. We need to be sure they're protected if there's a chaotic event."
Tuesday's hearing was mainly an informational event with APS officials outlining the plant's safety procedures and commissioners asking questions.
Commissioner Bob Stump said he wanted to learn about Palo Verde's backup power systems and how often the plant conducts emergency-procedure drills.
Problems arose at the Dai-ichi plant in Japan after a loss of power prevented its reactors from being safely shut down.
APS officials said Palo Verde's containment domes that prevent radiation from leaking into the atmosphere are significantly stronger than those at the Japanese plant.
APS's Chief Nuclear Officer Randy Edington also noted that Japan's nuclear accident was triggered by a tsunami and an earthquake, and said there's "low seismic activity in Arizona" and a tsunami likely won't ever reach the desert state.
He also said Palo Verde has multiple sources of reliable backup power and sufficient water on site to provide cooling at the plant for about one year.
"We've upgraded our emergency preparedness," said Edington, who also is an executive vice president at APS. "Any lessons learned from Japan's situation will be quickly applied. Our safety record is very good and we continue to work to do better."
Commissioners said APS officials gave them a guided tour of the plant Monday.
The Nuclear Regulatory Commission also plans to review the safety procedures at Palo Verde and other U.S. nuclear plants because of the situation in Japan. Commissioners said NRC officials were invited to Tuesday's hearing but did not attend.
Palo Verde's first two units went into commercial operation in 1986 with Unit 3 starting up in 1988. Newman said he was told the plant could expand by two more units in future years.
"I'm a strong supporter of nuclear power," Stump said. "But it's important to revisit the safety issue so we can reassure the public that procedures are sound."