Newspaper: The Evening Sentinel
Date: April 2, 1979
Title: Gas Bubble Decreasing, Radiation Levels Lower
Author: United Press International
HARRISBURG (UPI)-The crippled Three Mile Island nuclear reactor is steadily cooling down and the dangerous hydrogen bubble that blocked final shutdown efforts appears to have shrunk dramatically, a top Nuclear Regulatory Commission official reported today.
“I think it is certainly safer than yesterday,” said Harold Denton, NRC operations chief at the site, referring to the bubble which not only blocked final shutdown operations but also posed the risk of an internal reactor explosion.
Thousands of area residents, however, remain poised to evacuate if necessary.
DENTON SAID he still wanted to double check mathematical equations used to guess at the size of the bubble before saying with certainty the bubble had dramatically decreased in size. He said the calculation had been satisfactory while the bubble size was steady but may be flawed now because it leaves out other vrather than hours (on how to cool down the core),” Thompson told reporters at the NRC news center.
He also reported that general radiation levels outside the plant were declining although radiation inside the concrete containment building surrounding the reactor were at lethal levels.
It was because original efforts to eliminate the bubble produced no results that mass evacuation plans for the whole area were being considered.
Engineers at the site continued the slow process of starting to convert hydrogen gas in the containment building back to water to help cool the reactor.
The recombiners are designed to convert some of the hydrogen gas buildup in the containment building back into water by heating it with oxygen-a process similar to the way steam from a teapot is converted back into water vapor.
Once that is achieved, the engineers hope to use the reconverted water to help in the cooling process.
Success in the conversion attempt also would reduce the possibility of a second hydrogen gas explosion. Officials believe such an explosion damaged the facility last Wednesday, less than 10 hours after the nation’s worst nuclear accident began.
Authorities said the maneuver posed no new danger and Thornburgh-as if to stress that stance-ordered state employees to report for work as usual today in the state Capitol complex, 10 miles from the plant site. Carter-who 27 years ago was part of a Navy disaster in an experimental reactor at Chalk River in Canada-made a 26-minute on-site inspection of the mist-shrouded Three Mile Island plant Sunday. During his visit, he passed a wall of beige instrument panels that was covered with red, yellow, and white lights-and an occasional green one-showing the damaged reactor’s condition.
Later, he went to nearby Middletown, Pa., and told residents Thornburgh may have “to take further steps” to protect the population. He appealed to residents in the affected area to remain calm.
Civil Defense officials put six counties in central Pennsylvania on “advanced alert” Sunday for possible evacuation of the population in an area ranging up to 20 miles from the nuclear facility-some 636,000 people.
Thousands of residents already had fled the area because of the danger posed by the accident at the plant. There has been no official evacuation order, but Thornburgh suggested that pregnant women and pre-school children stay at least five miles away from the crippled nuclear facility.
The main task now faced by the engineers is to cool the reactor core so they can shut it down cold. Unless the fuel core can be cooled, the danger of a meltdown of the core-the worst possible nuclear catastrophe-could arise. The cooling process has been complicated by the hydrogen gas bubble engineers were now trying to eliminate.
Harold Denton, the Nuclear Regulatory Commision’s operation chief at the plant site, said the level of hydrogen in the containment building was increasing. But Denton said if the increase in hydrogen was due to a decrease in the size of the bubble, “that’s what we hoped to achieve.”
Carter, cheered and applauded enthusiastically by about 600 Middletown residents when he arrived at the local town hall, shook hands, grinned and waved to the crowd as he departed for Washington.
But inside the hall, the president appeared grim as he repeated three times that his main concern was the safety of the population.
“If we make an error, we want to err on the side of extreme caution and extra safety,” Carter said. “The health and safety of the people will be paramount.”
Carter stood in front of a basketball backboard-the town hall doubles as a community recreation center and, as of Sunday, served as the new NRC command post-with Thornburgh at his side.
He twice praised the townspeople for the calm with which they faced the nation’s worst nuclear accident and expressed “admiration of the citizens who behaved in such a calm manner.”
But Carter coupled the praise with an appeal to the people to remain calm “should Governor Thornburgh ask you to take further steps.”
Carter did not use the word “evacuate” or explain what “further steps” Thornburgh might ask people to take.
Joseph Hendrie, chairman of the NRC, has said it might be “prudent” to evacuate the entire population for up to 20 miles away from the nuclear plant if the hydrogen bubble which is complicating the cooling system cannot be eliminated by normal means and other, more risky methods must be attempted.
“Time is on our side in an event like this,” Denton said.