Canada's biggest electric power company, Ontario Hydro, has had serious safety problems at its nuclear power plants, including workers who operated reactors beyond their design specifications, played computer games, or slept on the job.
These and other longstanding problems became known for the first time this week after an Ontario court ordered the company to publicly release "peer review" documents that assess the operations of 19 atomic reactors at the company's nuclear power plants.
Ontario Hydro fought the release of the documents for more than a year, contending they would unduly alarm the public and harm the company by exaggerating its nuclear problems.
But nuclear-watchdog groups say the public has been well served. Tom Adams, executive director of Energy Probe, says releasing the documents has shown a needed "flashlight" on previously hidden problems.
'Plant safety has been jeopardized'
One such dark corner was revealed in a June 1995 peer review of the Pickering B plant east of Toronto on the shore of Lake Ontario, one of Canada's oldest nuclear facilities.
According to the report, crews sometimes operated the plant "beyond the safe operating limits." In July 1994, for instance, explosive deuterium gas was allowed to collect in Unit 5 of the complex in concentrations "three times the limit designed to avoid explosion."
The same report remarks that one nuclear-plant operator was observed sleeping and another playing a computer game. Meanwhile, a review of personal computers in the main control room showed three of the four machines had unauthorized programs or games installed on their hard drives.
"Safe operating practices and standards have not been effectively established," the Pickering B review said. "In some cases, plant safety has been jeopardized by the improper operation of important plant equipment, including some important to nuclear safety."
Weaknesses in operating-crew behavior, quality of procedures, and equipment performance "represent a significant erosion of defense in depth, and if not corrected, increase the probability of a significant event with serious consequences" - jargon that means an accident could happen.
Such reviews, the company says, are designed to be candid, even harsh - standard practice at nuclear facilities in North America since the 1979 accident at Three Mile Island, Pa.
Ontario Hydro conducts its own in-house reviews. In the United States, such reviews are conducted by the Institute of Nuclear Power Operators in Atlanta, an industry group. The release of Ontario Hydro's peer reviews is apparently the first time such reviews have been made public, an institute spokesman says.
"Hydro's first priority has always been and continues to be the safe operation of its nuclear stations," says Carl Andognini, Ontario Hydro's top nuclear official. "The information in these reviews points to the need for action but does not indicate immediate significant safety concerns." If there were immediate problems, the plants would be shut down, he says.
Ontario Energy Minister Norm Sterling told reporters that Canada's nuclear watchdog, the Atomic Energy Control Board, would quickly shut down reactors if there was ever any immediate problem.
Still, the problems revealed by the documents are unsettling, says Mr. Adams of Energy Probe. He points out that in several cases, longstanding management and other problems noted in earlier reviews were uncorrected and were being noted again.
While problems at Pickering B appeared to be the most severe, other nuclear sites had serious problems as well.
At the Bruce A facility, main control-panel "alarms are routinely silenced but not acknowledged," according to an October 1995 review. That action disables the control-room horn but leaves the "annunciator window" - a brightly lit button - flashing. During the review, multiple annunciator windows were observed flashing simultaneously, with some being allowed to flash for two hours.
The problem with such a practice, the reviewers state, is that it increases "the probability of missed alarms and could delay response to abnormal plant conditions."
The report says that in April 1995 an auxiliary pump failed, sounding an alarm at Unit 4 of the Bruce A plant during a shutdown. No action was taken in response for more than 24 hours. The pump failure resulted in no flow to a system that ensures an adequate supply of a chemical that keeps the reactor safe during a shutdown.
At the company's Bruce B plant, operators were seen playing computer games in the control room on two occasions, according to an October 1994 review. Also, on several occasions as many as 25 to 30 people might congregate in the control room making "a significant amount of noise" causing distractions for the operators and delaying their work. At the same facility, a "table tennis" table and net were set up between switchgear relay panels in the relay building.
'We have nothing to hide'
Ontario Hydro's Andognini says the information in the peer reviews is two to three years old and does not give an accurate view of current operations. Last October, Ontario Hydro announced a "nuclear recovery plan." In January, the company hired a new nuclear-plant management team.
A 1996 report on the Pickering A facility, the company's oldest, will be available soon, Andognini says.
"We have nothing to hide," he told reporters. "Safety is our No. 1 concern."