One of the key witnesses in the U.S. Department of Justice's case against three former Davis-Besse engineers is expected to testify today about the government's theory that he and the trio were part of a coverup that jeopardized northern Ohio's safety in the fall of 2001.
Prasoon Goyal, 61, of Toledo, who took the stand late yesterday, is a former senior design engineer who avoided prosecution by agreeing to cooperate with the Justice Department in its case against the other three.
Prosecutors said when the indictments were issued in 2006, Mr. Goyal and the three defendants - David Geisen, Rodney N. Cook, and Andrew Siemaszko - intentionally deceived the Nuclear Regulatory Commission about the dangerous state of the plant's old reactor head in the fall of 2001, when it was leaking boric acid from its reactor.
When the plant was shut down in early 2002, the NRC learned so much acid had leaked and burned through the plant's reactor lid that it nearly burst - an event that would have allowed radioactive steam to form in containment for the first time since half of Three Mile Island Unit 2's reactor melted in 1979.
The accusation of a coverup was based on the results of a two-year grand jury inquiry.
Mr. Goyal agreed to a one-year ban on employment in the nuclear industry in exchange for his testimony. He has not returned to Davis-Besse, where he had worked since 1986.
Mr. Geisen and Mr. Cook are being tried first. Mr. Siemaszko's trial is to follow. All three face up to five years in prison and separate $250,000 fines if convicted.
Earlier yesterday, an NRC metallurgical engineer, James A. Davis, who was part of the agency's augmented inspection team that was sent to the plant within hours after the near-rupture was discovered, testified that cracks in the old reactor head's most problematic nozzle likely started about 1990 - six years before any sizable leakage was documented and 12 years before the lid nearly blew.
Mr. Davis made a point of saying he was testifying as an independent witness and not as an NRC employee.
He said the nuclear industry and his agency have long settled on the average crack growth rate for reactor-head nozzles at 4 millimeters a year.
At that rate, it would have taken at least four years for a crack in one of those nozzles to develop a leak. Testimony last week revealed evidence of leaking as of 1996.
There are 69 such nozzles implanted in the reactor heads of pressurized-water reactors like Davis-Besse's.
They are made of a metal alloy that was found in France during the late 1980s to be susceptible to vertical cracks after years of high-temperature, high-pressure operation.
At 605 degrees, Davis-Besse was America's hottest-operating nuclear plant.
In 2001, the stakes were raised when the NRC learned that several U.S. reactor heads, especially Davis-Besse's, were susceptible to a more dangerous form of nozzle cracks, one that could form a circular pattern and pop off like champagne corks under an operating reactor's extreme pressure of 2,200 pounds per square inch.
Under that scenario, a flash of radioactive steam could form.
Mr. Davis testified that the cavity in Davis-Besse's reactor head - 5 inches wide, 7 inches long, and 6 1/2 inches deep - could not have been missed during FirstEnergy Corp.'s previous inspection in 2000 if the utility had done a credible job of inspecting the device.
Defense attorneys referred to a recent FirstEnergy consultant report, which claimed the bulk of damage could have occurred unbeknownst to anyone during the last three weeks before shutdown.
FirstEnergy is using that report to support its claim for a $200 million insurance payment on the grounds that the near-rupture might have been a fluke.
But prosecutors yesterday presented more evidence of a systematic, ongoing breakdown within the utility.
Greg Gibbs, a onetime Davis-Besse quality-assurance director and engineering director who left the plant in 1994, said he was disappointed after coming back as a consultant in 2001 to learn the utility never acted upon his insistence for larger holes in the reactor head's service structure to be used for inspections and cleaning.
A Blade investigation in 2002 showed that FirstEnergy vetoed a work order during the early 1990s for larger inspection ports, known as "mouse holes," to save $250,000, even after being encouraged to do the modification by officials at a plant in Crystal River, Fla., with a similar design.
The modification, which officials have said could have headed off Davis-Besse's problems, was done after the old reactor head nearly burst in 2002.
Contact Tom Henry at: email@example.com or 419-724-6079.