Subject: Comparing Japan's ill-fated Mihama NPP with San Onofre's NPPs

August 11th, 2004
North County Times

To The Editor:

Regarding the recent Back Page articles about the deadly reactor accident in Japan, local citizens should be informed of the fact that both San Onofre's operating reactors in San Clemente, California and the Mihama Nuclear Power Plant in Fukui Prefecture in Japan, which suffered an explosive steam leak two days ago, are all Pressurized Water Reactors between two and three decades old.

They all are probably made with substantially similar welding materials, pipe materials, pipe thicknesses, etc. etc..  They all probably suffer fairly similar rates of wear and tear, depending on how often they've been SCRAMed, what temperature they run at, what pressure they run at, how much time they've spent at operating temperature, and the quality of the metals and welds they are made with.

Have all parts of all pipes at San Onofre's two aging ("geriatric") reactors been inspected with Ultra-Sound, including all secondary loops?  I sincerely doubt it -- and I wouldn't trust the Nuclear Regulatory Commission or Southern California Edison to tell us, since it's a security issue (you can use a MUCH smaller charge to blow a hole in a thin-walled, old and embrittled, corroded pipe than in a thick, ductile new pipe).

San Onofre's reactors are slightly larger than the ill-fated Mihama NPP, and probably run hotter and under more pressure.  Therefore, they would age faster, all other things being equal.  The two operating San Onofre reactors are just a few years younger than the Mihama NPP.   That might mean we have a few years before a similar accident -- or worse -- is inevitable here.  But that's just guesswork at this point.  It is reasonable to assume we haven't got any time at all.

How much longer can we wait?  And why bother waiting at all, when cleaner energy solutions are abundant and ready to be tapped by modern technology?  In the short term, natural gas powered turbines (a remarkably clean energy source, all things considered) can replace ALL of San Onofre's energy output, safely and quickly. In fact, proven conservation efforts ALONE could do so!  So why -- dear God, why do we wait?

In one or two years, massive off-shore wind farms can be built, out of sight and unobtrusive, along with dozens of other energy solutions which have already proven themselves technologically, and only await public policy decisions that encourage government and private investment.

Just recently Southern California Edison workers snapped off a bolt on the earthquake restraints for the new and dangerous dry casks storage system, which wouldn't have happened if they understood the strengths of the materials they were working with (or perhaps, if they did not assume the bolts were as strong as designed).  (See NRC notification, below.)

California has been lucky so far, but luck -- good or bad -- ALWAYS changes eventually.  It's time to get smart about our energy choices, instead.

For additional urgent questions about San Onofre, please visit the following web site:


Russell Hoffman
Concerned Citizen
Carlsbad CA

Additional items included in this email:
1) JAPAN TIMES: Japan to probe nuclear accident
2) BOLT FAILURE: Power Reactor Event Number: 40897; Facility: SAN ONOFRE

JAPAN TIMES: Japan to probe nuclear accident:

Japan to probe nuclear accident

The plant was automatically shut down after the accident.


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TOKYO, Japan -- Japanese government officials are promising an investigation into the country's deadliest nuclear power accident.

A steam leak at a nuclear power plant northwest of Tokyo killed four workers and injured seven others on Monday.

Those who died were exposed to steam as hot as 200 Celsius (392 Fahrenheit), officials said.

Japanese officials said the leak from one of the reactors at the Mihama Nuclear Power Plant in Fukui Prefecture was not radioactive, Kyodo news agency reported.

Plant officials say ultrasound scanning might have detected the weakness in the pipes, but no such tests had ever been carried out in the 28-year-old facility.

The Japanese government has vowed to quickly find out what happened with Prime Minister Junichiro Koizumi promising a thorough investigation.

"We must put all our effort into determining the cause of the accident and to ensuring safety," Koizumi said, according to The Associated Press.

He added that the government would respond "resolutely, after confirming the facts."

Energy officials said no danger was posed to the surrounding area and no evacuation order was issued for the plant, which lies 320 kilometers (200 miles) northwest of Tokyo.

The accident struck at around 3:30 p.m. (0630 GMT) just after some workers had entered the facility to take measurements ahead of a scheduled shutdown for maintenance, NHK reported.

The 826,000-kilowatt pressurized-water reactor, which began service in 1976, was automatically shut down after the accident.

Japan depends on nuclear power for about one-third of its electricity. The Mihama plant was the first nuclear plant built by Kansai Electric Power Co. Inc.

"We are now investigating the cause," a Kansai Electric official told a news conference.

The accident was the worst since 1999, when a radiation leak at a fuel-reprocessing plant in Tokaimura killed two workers and affected hundreds of others, according to The Associated Press.

That accident was caused by two workers who tried to save time by mixing excessive amounts of uranium in buckets instead of using special mechanized tanks.

A string of safety problems since has undermined public faith in nuclear energy and left Japan's program in limbo.

Copyright 2004 CNN. All rights reserved.This material may not be published, broadcast, rewritten, or redistributed. Associated Press contributed to this report.

BOLT FAILURE: Power Reactor Event Number: 40897; Facility: SAN ONOFRE:


      "On July 24, 2004, at about 1000 PDT, SCE [Southern California Edison]
personnel were tightening two seismic restraint bolts on Advanced Horizontal
Storage Module (AHSM) Number 10 at the Unit 1 ISFSI [Independent Fuel
Storage Installation] when one of the bolts failed. SCE had placed the
storage canister into AHSM No. 10 on July 18, 2004 and was tightening the
restraint as specified in the final safety analysis report, after the module
had reached thermal equilibrium.

      "SCE plans to replace the failed bolt with another bolt manufactured
under the same Certificate of Compliance and will tighten the seismic
restraints within the period allowed by the FSAR (one week from initial
placement of the storage canister). SCE's evaluation of the failed bolt is

      "SCE has notified the NRC resident inspectors about this occurrence
and will provide them with a copy of this report."

Authorship notes:

This email was written by Russell D. Hoffman from 100% recycled electrons.