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Southern California Edison Posts Library Of San Onofre Documents

SAN DIEGO (CNS) - A digital library containing nearly 100 documents related to the replacement steam generators at the shuttered San Onofre Nuclear Generating Station in northern San Diego County was made available online Wednesday.

Photo by David McNew

The San Onofre Nuclear Generating Station at San Onofre State Beach in a 2012 photo.

The library, which includes more than 3,200 pages, can be found at Some of the documents are partially redacted, according to Southern California Edison.

"The San Onofre Digital Document Library will help the public, elected officials and regulators better understand the history of the replacement steam generators that led to San Onofre's closure,'' said Ron Litzinger, president of SCE. "It is vitally important that we all achieve a full understanding of the facts so that future decisions by regulators and legislators are based on transparency and the highest quality information.''

A small, non-injury leak in January 2012 resulted in the shutdown of one of the reactors at the seaside plant. Edison, the operator and majority owner of the facility, determined the cause to be vibrations in pressure tubes in the steam generators, which were manufactured by Mitsubishi Heavy Industries and installed in 2010 and 2011.

The plant's other reactor was undergoing maintenance at the time. Neither reactor was ever restarted.

A plan by Edison to put the unit that was being worked on back into service at 70 percent power ran into regulatory problems earlier this year, and the utility decided it would be more economical to close the reactors permanently. The dismantling process is expected to take several decades.

According to the utility, the San Onofre Digital Document Library contains a wide variety of documents, many made public for the first time. The online collection supplements data that SCE had previously made publicly available at

The redactions in some of the documents were made because Mitsubishi has asserted that those sections contain proprietary information that cannot be made public, according to SCE. The utility said it has asked the Japanese firm to agree to the public release of unredacted versions of the documents.

Edison officials said they plan to add other documents to the library, and are asking Mitsubishi to confirm that the data can be placed online without redaction.

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