Salp clogging water intakes at Diablo Canyon nuclear reactor
By Steve Chawkins, Los Angeles Times
26 April 2012
Strange, jellyfish-like creatures swarming a coastal nuclear power plant: It might sound like the premise of a cult horror flick, but the invasion has prompted officials at the Diablo Canyon facility in San Luis Obispo to curtail operations for at least a few days. The plant’s operator, Pacific Gas & Electric, cut power generation from one of the plant’s two reactors to 25% of its capacity, spokesman Tom Cuddy said Wednesday. The other reactor was shut down this week for what PG&E described as routine refueling and maintenance, a procedure that could take about a month. Workers on Monday discovered an influx of the creatures, called salp, clogging screens that are used to keep marine life out of the seawater used as a coolant, Cuddy said. Often thronging many square miles of ocean in huge, gelatinous masses, salp are tubular, transparent organisms that can be roughly the size of a human thumb. No one knows how many are at the Avila Beach plant or how long they will remain. “We’ll continue to monitor the intake structure and clean the salp off the screens,” Cuddy said. “Once they decide to move on and it’s safe to do so, we’ll resume full power.” That could take several days, he said, but no blackouts or interruptions are anticipated. Jellyfish swarmed Diablo Canyon in 2008, triggering a steep, sudden decrease in power generation. Over the years, they have been a problem at nuclear plants in the U.S., Japan, Israel and Scotland. The San Onofre plant in northern San Diego County, while currently closed over several equipment issues, has not had a jellyfish problem, according to a spokeswoman for its operator, Southern California Edison. Salps do not usually go coastal. “Ordinarily they live further out at sea,” said Larry Madin, a salp expert and research director at Woods Hole Oceanographic Institution in Massachusetts. “It sounds like these were brought in on a current or blown in by wind.” […]
