A ticking time bomb? An ageing nuclear infrastructure., page 1

OK was just checking hisz.rsoe.hu... as is my want on a daily basis.

Found another Nuclear event in the US. Had a check as I thought I had seen a few similar in recent days. I had.

5 unusual events since the 12th of August.

hisz.rsoe.hu...

Spokesman Mike Bradley says an ammonia-water leak developed in a secondary water system at the turbine building at the plant. That happened just before 9:00am. Between two and three hundred employees were evacuated as a result. The leak was fixed and the event was declared over just before 1:30pm this afternoon. Bradley says the leak did not disrupt the reactor. There were no injuries and there was no risk to the general public.

hisz.rsoe.hu...

The Palisades nuclear plant in southwestern Michigan has been removed from service to repair what officials said is a "very small, very minor" cooling water leak. No radioactive materials were released, spokesman Mark Savage said Sunday. The leak was being repaired inside a containment building at the plant in Covert Township, southwest of Grand Rapids. "Palisades is taking this conservative measure at this time because of our unrelenting commitment and focus on nuclear safety," Savage said in Sunday morning in a release. "Palisades will be returned to service when repairs are completed."

hisz.rsoe.hu...

A reactor at the Millstone nuclear plant in Waterford, Conn., has shut down because of something that its 1960s designers never anticipated: the water in Long Island Sound was too warm to cool it. Under the reactor’s safety rules, the cooling water can be no higher than 75 degrees. On Sunday afternoon, the water’s temperature soared to 76.7 degrees, prompting the operator, Dominion Power, to order the shutdown of the 880-megawatt reactor. “Temperatures this summer are the warmest we’ve had since operations began here at Millstone,’’ said a spokesman for Dominion, Ken Holt. The plant’s first reactor, now retired, began operation in 1970. The plant’s third reactor was still running on Monday, but engineers were watching temperature trends carefully out of concern that it, too, might have to shut down. A spokeswoman for the regional grid control center, ISO-New England, said the shutdown had not impaired the functioning of the grid because generation has been more than sufficient. But in periods when industrial demand for electricity has been stronger, a reactor shutdown has sometimes forced grid operators to scramble.

hisz.rsoe.hu...

Authorities are looking into an incident at the Calvert Cliffs nuclear plant, located 70 miles south of Baltimore in Maryland. The malfunction poses no risk to the public, but it did cause a major drop in power generation. A spokesman said Monday that a control rod unexpectedly dropped into the reactor core. Control rods are used to regulate the pace of the nuclear reaction. Dr. David Lochbaum is a nuclear expert with the Union of Concerned Scientists, a watchdog group. He says these types of events happen about once every two years at most U.S. nuclear plants.

hisz.rsoe.hu...

Prairie Island nuclear plant shut down Unit 1 after operators declared its two backup diesel generators inoperable Tuesday. Staff determined during routine testing that both generators had exhaust leaks, Xcel Energy media relations spokeswoman Mary Sandok confirmed. That deemed them inoperable, and the plant filed an incident report of the safe shutdown with the Nuclear Regulatory Plant. Prairie Island has other backup protection, including diesel generators and turbine-driven and portable pumps, the company said in the statement issued at 2:30 p.m. There was no radiation leak or danger to the public. Prairie Island Tribal Council President Johnny Johnson called the loss of both generators “not acceptable.” “A failure of the back-up diesel generators can affect all other safety features that rely on the electricity that they generate,” he said. The plant has had more than 30 reported incidents of failing equipment, security breaches, human performance problems and operating errors in recent years, he said.

Not trying to scare monger as none of these events is particularly dangerous but just want to point out what the future may hold. Most of these designs were conceived in the 60's and 70's.

From wikipedia en.wikipedia.org...

US nuclear reactors were originally licensed to operate for 40-year periods. In the 1980s, the NRC determined that there were no technical issues that would preclude longer service.[36] Over half of US nuclear reactors are over 30 years old and almost all are over twenty years old.[37] As of 2011, more than 60 reactors have received 20-year extensions to their licensed lifetimes, with more than a dozen applications still under review.[38] The average capacity factor for all US reactors has improved from below 60% in the 1970s and 1980s, to 92% in 2007,[39] more than compensating for the retirement of older reactors.[40

I firmly believe that profit driven attitudes to maintenance and upkeep will cause a significant threat to safety as these plants get older,