PHOENIX (AP) -- By 6 a.m., Michelle Catts is making her way to the office past guards armed with automatic weapons, ultra-sensitive X-ray machines, electronic gates and sensors that sniff out explosives.

Cooling towers at Palo Verde Nuclear Generating Station in Wintersburg send wisps of steam into the desert air, and Catts can take in the view from her window as she reads daily reports about the plant that produces more power than any other U.S. power plant.

Catts is one of four Nuclear Regulatory Commission inspectors at the plant serving as government watchdogs to make sure Arizona Public Service Co. finds problems before they affect safety - a more critical task after a string of safety issues dating to 2003.

"My job every day is to make sure this plant is operating safely," Catts said. "That's a pretty important job. It's a good feeling at the end of the day to know I found important things to ask about."

Catts asked to work at Palo Verde after the NRC placed the plant in Category 4, one level above being shut down. It was a rare opportunity for the 28-year-old, who became the only female NRC inspector working west of the Mississippi.

She has spent her first year poking around three reactors, helping ensure the plant reinvigorates its "safety culture," eventually getting it out of the regulatory doghouse.

Much of her work involves walking around, flashlight in hand, to examine everything from giant turbines to the control room, where she quizzes operators with decades of experience, ensuring they are paying attention to the plant's vital operations.

Catts emphasizes that she and the NRC are most concerned with safety and reliability, not with how profitable the plant is for APS, which operates Palo Verde for seven owners that share its electricity.

Still, the relationship of reliability and profit is direct. If APS fails to identify equipment problems before it's too late, the plant can trip off-line or be forced to power down, and the utilities that rely on it for power, including Salt River Project, must turn to more expensive natural-gas-fired plants for their customers' electricity.

Being proactive about finding problems, APS can fix them during routine refueling outages and stay out of regulatory trouble.

One recent morning, APS officials reported a small oil leak in a backup diesel generator but determined it wasn't significant and kept the reactor going.

"I'll challenge them on this," Catts said. "If you live with this (and don't shut things down to fix it immediately), is the generator still going to perform its safety function?"

NRC inspectors must be inquisitive, Catts said.

"I was always a really curious kid, always asking why," she said. "I drove my mom and dad crazy. In high school and college, I took more math classes and realized I liked it."

She graduated with a degree in nuclear engineering from North Carolina State University in 2003 and worked for a utility briefly before being hired by NRC in Philadelphia, covering plants in the region, before being assigned to Palo Verde.

"It's not the most glamorous job," Catts said. "I don't get to wear high heels and a dress to work. I've got to wear big ol' work boots."

She's one of 31 inspectors in the region, overseeing 21 nuclear reactors in the West, and one of just eight women among the NRC's 147 resident inspectors nationwide. Resident inspectors like Catts report to a senior inspector also on site at the plants.

Annual salaries depend on experience and in what region of the country resident inspectors work, but the scale ranges from $78,700 to $102,000 in Phoenix, according to NRC. For all the media coverage of Palo Verde, the plant has not had major problems with leaking radiation. Its problems involve mostly equipment maintenance and how the operators responded.

Catts usually ends her day by 4 p.m., but she carries a pager so that she can respond anytime, like last year when a contract worker was stopped at the front gate with a pipe bomb in the bed of his pickup, or when a small fire started outside.

The NRC allows inspectors to spend seven years at one plant, meaning Catts' time is limited.

"They make sure there's always fresh eyes on a site," she said. "That we don't get too close to them and that we are the tough regulators we are supposed to be."

---

Information from: The Arizona Republic, http://www.azcentral.com

© 2008 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Learn more about our Privacy Policy.