It was August 30, 1976, 2:45 a.m. on the graveyard shift when McCluskey entered the Americium Recovery Room, Building 242-Z of the Plutonium Finishing Plant. The operator on duty turned the recovery task over to him and left, and a few minutes later the junior chemical operator showed up to assist, observe, and learn.
Americium-241 is a transuranic byproduct of plutonium production. Rather than throw it away into the atomic landfill, Atlantic Richfield found that it was a valuable substance that could be sold and offset the cost of making fissile bomb material. This particular nuclide decays with a powerful alpha-particle emission, much like polonium-210, but unlike polonium with its short half-life, this species would outlast a Galapagos tortoise. Only half of it is gone after 433 years, and this makes it an attractive material for use in air-ionizing smoke detectors. Eventually every house in the country will have at least one smoke detector stuck to the ceiling, and that will require a lot of americium. It decays into neptunium-237 with a spray of gamma rays accompanying the alphas. The neptunium stays around for about two million years.
It is removed from fission waste products in very small batches, about 10 grams each, by dissolving it in 7-molar nitric acid and dribbling it down through a long cylindrical column filled with Dowex 50W-X8 ion-exchange resin beads. This process is observed, controlled, and adjusted using a large glove box, which allows the worker to insert his hands into two long-sleeved rubber gloves, bolted to the front of a metal workstation. The worker can manipulate objects in the glove box as if they were on a tabletop, yet he or she is completely isolated from the materials in the tightly sealed box, never directly touching anything. No radioactive contamination can get through the gloves or the box, and the worker is perfectly safe. He or she can see the work through the lead-glass window.
A general-purpose glove box is a simple affair, having a wide, tilted window on the front and two gloves at elbow level, but the americium recovery glove box was tall and rather strange. Each station in the line of americium boxes had not two but six glove positions, so that you could get hold of something at the top, the middle, or the bottom of the 6-foot ion-exchange column. There were seven windows. One long, thin window, right in front of the column, came down from the top, halfway to the floor. Five diamond-shaped windows were spaced all around, and a triangular window was at the top on the right side, all giving special viewing to certain parts of the chemical extraction process. Each window was made of laminated safety glass, to prevent shattering, covered with quarter-inch lead glass for gamma-ray protection. The inside of the box was dominated by the metal column, festooned with a confusion of tubes, valves, and conduits. There was a two-step metal ladder to help you see the top of the column and put your hands into the upper set of gloves. To work in the Americium Recovery Room, you had to love complexity and the fact that not just anybody could do this.
It was unfortunate that the americium recovery had been shut down for five months due to a labor dispute, and starting it up again was not going to be trivial, which is why an old-timer like McCluskey was on board. As it turned out, when the workers struck, the column was left in mid ion-exchange with acid on top of the resin and the drain valve at the bottom closed. In five months of sitting there, the resin beads had compacted into an unnatural configuration, saturated with americium.
McCluskey stood on the top ladder step and opened the valves on the column to get the process started, with the americium dissolved in acid dripping into the resin. Satisfied that it was started, he retraced his steps through a narrow corridor and back to the control panel desk, where the junior engineer was sitting.
He had just sat down, verbally downloading wisdom to his young associate, when the junior engineer interrupted the conversation. He heard something. Hissing. Like, a steam leak? McCluskey got up and went back to the recovery station, listening and following the sound. The entire glove box was filled with dense brown smoke. Uh oh. He shouted to the junior operator, telling him to call the control room up on the fourth floor and ask for help. Junior had just arrived at the glove box. He took one quick look and ran to the intercom back at the desk.
McCluskey climbed the stepladder and put his hands into the top gloves. They felt strangely warm. Had he forgotten to open the drain valve? He tried it. It was already open. He could not see the pressure gauge because the fumes were so dense, but now he could hear a new hiss, out the bottom of the column. He turned his face to the left and called out to junior, “It’s gonna blow!”
WHAM tinkle tinkle. The operator in the control room heard it over the intercom as the resin column disintegrated in a heavy blast, and the junior operator turned around to see the cloud of debris make it through the corridor maze and to the desk. As soon as his ears cleared, he heard McCluskey’s voice. “I can’t see! I can’t see!”
Junior ran to him and found him knocked to the floor, covered with blood, and the room socked in with americium fog. The windows in the glove box were blown all over the room, two gloves had turned inside out, and three gloves were simply gone. He tried to hold his breath as he rolled McCluskey over and helped him crawl back past the desk and to the outer door. Just then, the control-room operator, having heard and felt the explosion, was scrambling down the stairs to see what was going on, and he saw Junior and McCluskey near the door. He called back to the man following behind him, “A tank has blown up. Call the ambulance and shut down the plant as quick as you can.” It was 2:55 a.m., only 10 minutes after McCluskey had clocked in.
At that instant, a health physicist, trained to monitor radiation and assist in any emergency and called “HP,” ambled through the door and immediately perceived that an explosive radiation release had occurred. The potential for further contamination was obvious to him. He held up both hands and said, “Stay right there. I’ll come and get you.” He turned to the control room operator and told him to back off. No sense getting more people contaminated. He opened the emergency cabinet, pulled a respirator mask over his head and tossed one to Junior and one to the control room operator, telling them to put them on.
As Junior tried to adjust his mask so he could breathe, he heard HP’s muffled voice saying, “We’ve got to get him under some water.” McCluskey looked like he was about to faint. It had to sting like hell, particularly with the nitric acid in his eyes. HP and Junior took him to the emergency shower in the next room, but they hesitated to put him in it. The water would be ice-cold. They were afraid that with his well-known heart condition, the temperature shock could kill him. They stripped off his clothes, took him to the sink on the opposite wall, and sat him down on a stool. HP wiped McCluskey’s face with wet rags while Junior scrounged more rags and some soap.
They tried to keep McCluskey conscious and talking. The glove box had blown up, he said. The last thing he saw was a blue-white flame. HP knew that no criticality alarm had gone off, so it was not a rogue chain reaction with plutonium, as was constantly the concern. It had to have been a chemical reaction, but unfortunately it was a big one. McCluskey’s face and neck, particularly the right side, were perforated with bits of glass, heavily contaminated with radioactive americium-241. His eyes were swollen shut. The right one looked particularly bad, with “black stuff” around it and his right ear, and there was a cut above on his forehead.