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The locals are getting nervous with a nuke in their backyard. Wait until there are blackouts this summer because San Onofre Units 2 & 3 aren’t running, that will show those ratepayers whose boss.

Funny, usually KPBS (was government funded) would be supporting nuke power.

From http://carlsbad.patch.com/articles/san-onofre-sdge-nuclear-power

Some Nuclear Parts Shot; San Onofre Shutdown Costs Up to $1 Million a Day By Adam Townsend
February 4, 2012

The San Onofre Nuclear Generating Station spent hundreds of millions of dollars on new steam generators in the last couple years, and now some heat exchanger tubes are nearly worn out.

Crucial components that contain high-pressure, radioactive water at the San Onofre Nuclear Generating Station are, in many places, nearly too worn to function, said an Nuclear Regulatory Commission spokesman.

There is no danger to plant workers or the public because both reactors at the San Onofre station are shut down—one for maintenance and one because of a leak that started Tuesday.

But, the components are only one to two years old and cost hundreds of millions of dollars, raising troubling questions about their functioning.

The plant is producing no electricity. As crews are assessing and planning repairs to leaks at Unit 3 at the plant, the unplanned shutdown, an expert told KPBS, is costing Southern California Edison from $600,000 to $1 million per day.

Problems have been identified in the heat-exchanger tubes that boil water in the steam generators at the plant; there are two generators in each of the two reactors at the plant.

The high-pressure, superheated, radioactive water that runs through the tubes has started to wear through walls of the heat exchangers.

“They’ve looked at about 80 percent of the tubes in Unit 2,” said NRC spokesman Victor Dricks. “Two of the tubes have more than 30 percent wear and have to be plugged and taken out of service. Sixty-nine others have more than 20 percent wear. Over 800 others have less than 20 percent wear, but more than 10 percent.”

These aren’t the leaky tubes that caused the Tuesday shutdown of Unit 3 at the San Onofre plant, but the same component at Unit 3 has been isolated as the site of the leak.

Unit 2 has been shut down to replace the massive turbines and reactor head at the unit. The wear was detected as part of the routine inspection of equipment that technicians conduct before restarting the reactor, whether for a routine refueling outage or for refurbishments like the turbine replacement.

Public relations people at Mitsubishi, the manufacturer of the components in question, did not immediately return calls for comment Friday morning.

The damage raises questions about possible flaws in the multi-million-dollar, custom-made components, but there are dozens of factors that could be involved. Contractors installing the equipment, shipping personnel and plant staff all have roles to play in the installation and operation of the steam generators.

Mitsubishi representatives are on-site consulting as Southern California Edison crews investigate the damage.

“They (SCE) are talking with the manufacturer,” Dricks said. “It’s unusual. They’ll have to determine what caused it.”

The tubes are heat exchangers. The nuclear fuel rods super-heat water within a primary system. This water runs through these hundreds of tubes, set up like a car radiator, at a pressure of about 2,500 pounds-per-square-inch.

The heat boils water in a secondary system that makes steam to turn giant turbines. The electricity generated by San Onofre can power more than a million homes at any given time.

San Diego Gas & Electric owns a significant stake in the plant, but SCE is charged with maintaining and operating it.

From...

http://articles.latimes.com/2012/apr/13/local/la-me-0413-san-onofre-20120413

Odd deterioration found in both San Onofre reactors
Energy officials had said tubes at San Onofre’s reactors were experiencing different types of wear. Now they say the unusually fast deterioration is occurring at both of the closed plant’s reactors.

April 13, 2012|By Abby Sewell, Los Angeles Times

Southern California Edison officials said that they are now seeing the same unusual type of wear on steam generator tubes at both of the San Onofre nuclear plant’s reactor units, which have been shuttered for months.

Officials found excessive wear in recent months on more than 300 tubes that were installed as part of the $671-million replacement of the plant’s four steam generators. The new steam generators, manufactured by Mitsubishi Heavy Industries, were installed within the last two years, which made the rate of deterioration startling.

What was even more unusual was the type of wear. U.S. Nuclear Regulatory Commission officials said the tubes in Unit 3 were vibrating excessively and rubbing against each other. Initially, they said that the wear at Unit 2 appeared to be different.

But in a statement Wednesday, Edison said that during its ongoing testing it had found additional wear in Unit 2 of a type that is “similar to the type of wear that was seen in Unit 3, but at a very low level.”....