Information sur le nucléaire

CONTROVERSES NUCLEAIRES !
ACTUALITE NUCLEAIRE
2008
août
USA: Engineer Lied to Nuclear Regulators
Ohio Nuclear Engineer Convicted of Lying About Cracks in Reactor
Sources:
hosted.ap.org ShortNews.com - Regensburg, Germany
Environment News Service - USA

hosted.ap.org ShortNews.com - Regensburg, Germany 26/08/2008

     Andrew Siemaszko, a former nuclear plant engineer, and two other workers have been convicted of concealing material information for lying to regulators about extreme corrosion at a U.S. nuclear reactor along Lake Erie.
     Siemaszko lied to delay a safety inspection at the Davis-Besse plant which was later found to have an acid leak so severe it had nearly eaten through the reactor's 6-inch-thick steel cap. Regulators are unsure how close the plant was to an accident.
     Siemaszko is facing up to five years in prison and a $250,000 fine during sentencing.
     ... at a US nuclear reactor along Lake Erie. Siemaszko lied to delay a safety inspection at the Davis-Besse plant which was later found to have an acid leak ...

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Environment News Service - USA
Ohio Nuclear Engineer Convicted of Lying About Cracks in Reactor

TOLEDO, Ohio, August 26, 2008 (ENS) - At Oak Harbor, Ohio, 21 miles southeast of the city of Toledo, lies the Davis-Besse Nuclear Power Station, where a hole the size of a football was discovered in the head of the nuclear reactor vessel in March 2002.
Today, a federal jury in Toledo convicted a former reactor coolant system engineer at the facility of lying to the Nuclear Regulatory Commission about the safety condition of that reactor vessel head.

The Davis-Besse nuclear power plant at Oak Harbor, Ohio. (Photo courtesy NRC)

     "Today, after hearing all the facts, a federal jury convicted Andrew Siemaszko for concealing the truth from the Nuclear Regulatory Commission," said Ronald Tenpas, assistant attorney general for the Justice Department's Environment and Natural Resources Division. "The effectiveness of the NRC's regulation and the safe operation of the nation's nuclear power plants depends on honest and forthright information."
     The evidence at trial showed that during the fall of 2001 Andrew Siemaszko falsely represented to the NRC that past inspections of the reactor vessel head at Davis-Besse were adequate to assure safe operation of the facility until spring of 2002 when the utility operator, FirstEnergy Nuclear Operating Company, had scheduled a regular refueling shutdown.
     During that refueling outage, workers discovered the hole in the head of the reactor vessel, the container where the nuclear reaction occurs.
     Analysis showed the hole resulted from a leak of corrosive reactor coolant containing boric acid through a crack that had opened where control rod guide nozzles were welded to the lid of the reactor vessel.
     Boric acid is dissolved in a plant's reactor coolant water. Inspections revealed that there were deposits of boric acid on the reactor head that got worse over time and eventually blocked holes that should have been used for inspections.
     Siemaszko's false statements to the NRC were in response to a bulletin issued by the agency in August 2001 that warned of a cracking problem at similar plants and sought information about Davis-Besse.
     This nozzle cracking problem had first been observed at similar U.S. plants in late 2000, and the NRC warned in the bulletin that it could lead to breaks where the nozzles penetrated the lid of the steel-walled reactor vessel.
     Such a break could release pressurized reactor coolant water into the containment building. The NRC estimated that if Davis-Besse had operated for another two to 11 months, the damaged reactor vessel head could have failed, causing a serious loss of coolant accident. A near-meltdown had been narrowly averted.

The NRC bulletin warned that small boric acid deposits were a sign of nozzle cracking. In the bulletin, the federal agency required FirstEnergy Nuclear and other utilities to report on their plants' susceptibility to cracking, the steps they had taken to detect it and their plans for addressing the problem in the future.
Because FirstEnergy Nuclear chose not to inspect the nozzles before December 31, 2001, it was also required to justify operation beyond that date.

Boric acid corrosion on the Davis-Besse reactor vessel head
(Photo courtesy NIRS)      In the months following the issuance of the bulletin, FirstEnergy Nuclear submitted to the NRC five letters that included details of past inspections.
     The jury determined that they were based in part on false information that Siemaszko contributed about his own inspection of the reactor vessel head and information based on video records of inspections conducted by others.
     Video evidence presented to the jury of the inspection performed by Siemaszko in 2000, showed that the camera used for inspections was physically blocked by boric acid deposits and that very few of the nozzles that were the subject of the NRC's bulletin could be assessed for cracking.
     At trial, the government proved that Siemaszko knew that he had given false reports and that he presented information orally to the NRC that emphasized false conclusions, including the statement that he was "at peace in his soul" regarding the 2000 inspection results.
     Siemaszko was convicted of concealing the condition of Davis-Besse's reactor vessel head and of concealing how poor past inspections of that head had been.
     He also was convicted of using false writings in FirstEnergy Nuclear's interactions with the NRC, including false statements about the extent of inspections done in 1996, 1998 and 2000.
     After the cavity in the Davis-Besse reactor vessel head was discovered, FirstEnergy Nuclear disciplined a number of its employees. Siemaszko was fired and brought a whistleblower complaint against the company.
     According to a Department of Labor investigator who testified at the trial, the complaint was fully investigated and dismissed. The investigator testified that Siemaszko admitted during the whistleblower investigation that he lied to the NRC and was terminated for that reason.
     Special agents of the NRC's Office of Investigations and a senior reactor inspector from NRC's Region III developed the case and referred it to the Department of Justice.
     The investigation and prosecution were conducted jointly by the Justice Department's Environmental Crimes Section and by the U.S. Attorney's Office for the Northern District of Ohio, as well as the NRC Office of Investigations.
     Siemaszko's co-defendant David Geisen was convicted on October 31, 2007, on similar charges. Another co-defendant, Rodney Cook, was acquitted. Sentencing in for Siemaszko has not yet been scheduled.
     Siemaszko has supporters who do not believe that he is guilty as charged. The Union of Concerned Scientists and the advocacy group Ohio Citizen Action both say Siemaszko is innocent.
     Ohio Citizen Action composed a letter for its followers to send to government officials that says, "The records of Mr. Siemaszko's actions show that he was carrying out his job of cleaning the reactor head in good faith until management brought a halt to the work. By FirstEnergy's own admission, the root cause of the problem began in the mid-1990s, several years before Mr. Siemaszko was even employed at the plant."
     FirstEnergy Nuclear is a subsidiary of FirstEnergy Corp, based in Akron, Ohio. In April 2005, the company was fined $5.45 million over the Davis-Besse reactor head incident, the largest single fine ever proposed by the Nuclear Regulatory Commission.
     The main violation was that the utility restarted and operated the Davis-Besse plant in May 2000 without fully characterizing and eliminating leakage from the reactor vessel head, which led to significant corrosion damage.