Episode 24
**********
May 11, 1986
Time: 2:51:12 am.
Reactor Water Level (above Fuel): 192 inches (normal)
Reactor Pressure: 1000 pounds per square inch (normal)
Drywell Pressure: 1.1 pounds per square inch (normal)
Drywell Temperature (Air): 120 degrees Fahrenheit (normal)
Torus Pressure: 0.8 pounds per square inch (normal)
Torus Temperature: 84 degrees Fahrenheit (normal)
Electric Power Systems:
Offsite Power Line (normal source): Operable
Backup Offsite Power Line: Down
Emergency Diesel Generator #1: Operable
Emergency Diesel Generator #2: Under Repair
Batteries: Operable
Water and Safety Systems:
Electric-Powered:
Feedwater: Operable
VEPI: Operable
Fuel Spray: Operable
Steam / Battery-Powered:
STURDI-1: Operable
STURDI 2: Operable
Compressed Air and
EmShut: Operable
Wendell finished up the log entry regarding the loss of the backup offsite power supply, while through the glass he could hear Fleck describing his new car to the two men at the operator's table.
Darkness.
The control room exploded with alarms, the walls lit with blinking rectangles as horns began to blare. Wendell jumped up. What.....?
“Reactor scram!” the chief operator announced.
“No offsite power! I'm covering diesels!” the assistant operator said.
“Main steam valves have closed,” Fleck said. He remained beside the table. “The vessel is isolated. We've lifted a relief.”
Wendell ran into the control room and headed for the center panel. Loss of offsite power: steam lines fail shut -- feedwater pump dies -- you get a diesel start.
“All rods full in!” the chief operator announced as Wendell came up alongside. On the wall above, the circular control rod display had changed from red to green.
“No diesel start!” the assistant operator shouted from a panel on the left. “No diesel start! Trying manual!”
Shit! Wendell began scanning the center panel. Where we at? What's level? It was difficult to see in the faint emergency lighting. Alarms continued to blare.
“No manual start!” the assistant operator said. “No diesel start on manual! Damn!”
There. “Level at 1-5-6 inches!” Wendell said.
Fleck pointed at the chief operator. “Larry, get STurDI-1 running.”
“STurDI-1!” the operator replied, as he began manipulating controls.
“Reactor pressure 920, falling,” Wendell reported. “Torus temp nearing 90 .... rising.” Excess steam was being diverted into the huge torus tank by a pressure relief valve.
“Tried manual again, no diesel start!” the assistant operator said. “No bad readings, but no R.P.M.!”
Come on, we gotta have that diesel.
Fleck grabbed the radio mike off the table. “DeMira! Get to the #1 diesel on the double!” he said to the turbine building operator on rounds. “Start it locally! Acknowledge!”
“Roger, on my way!” the speaker crackled.
“Zabowski!” Fleck said next, addressing the reactor building operator in the plant. “Diesel! Go help DeMira!”
“Roger!”
“Level at 152!” Wendell said. “Creeping down!”
“Starting STurDI-1!” the chief operator shouted over the alarms.
“Drywell air at 175 degrees, mid-level,” Wendell reported. Not so good. He turned off an alarm.
The assistant operator cut the annunciator horn at his station as well, and, abruptly, the control room was quiet.
Wendell’s rapid breathing punctuated the stillness. He watched the water level indicator for the reactor vessel. STurDI-1 should be kicking in…
A new alarm began blaring.
“STurDI failed to start!” the chief operator said. “Startup oil pump shut off early!”
“STurDI-2,” Fleck ordered.
“Trying STurDI-2!” the chief operator repeated. “Lining up.”
“P.R.V. has closed, pressure rising again,” Wendell announced. “Level's down to ... 147.” STurDI-2 better work, or we’re screwed. The small turbine-pump was now the only way to put water into the reactor vessel.
“Starting STurDI-2!”
Come on, come on…
“STurDI-2 no start!” the chief operator yelled frantically. “Trying again! ... No start! Nothing!” He smacked his leg. “Fuck!”
Wendell grimaced. Jesus, this can't be for real. Can’t.
At the operator's table, Fleck spoke into the radio: “Zabowski!” he ordered the reactor building operator, “skip the diesel and get down to STurDI-1! ... then 2!”
Wendell continued to watch the vital indications. “Level at 145, slow decline,” he said. “P.R.V.'s are in pressure control mode. Auto circuit on.”
Behind him, Fleck put aside the mike. “God damn, this is screwed up.”
Wendell could only agree. Fairview Station was in deep trouble. They had lost all offsite electric power, and the one available diesel generator, designed to operate VEPI or Fuel Spray, was not working. Neither were the STurDI-1 and STurDI-2 systems. Slowly, the water covering the core was boiling away due to the heat remaining in the shutdown reactor -- and there was no way to replace it.
“I'm trying STurDI-1 again,” the chief operator said. “Then STurDI-2.”
“Good,” Fleck said. Behind him the STA was now feverishly reviewing the emergency procedures.
An alarm horn sounded and was promptly quelled. “Control!” a voice now crackled on the radio.
Fleck grabbed the microphone. “Control.”
“This is Zabowski.” It was the operator sent to the STurDI area. “Reactor building is locked!” he reported. “Access cards don't work. I’m going over to Security to get a key.”
Fleck signed off. “Damn. All the doors with card readers will be like that.”
“He should have most of the keys with him,” Wendell said.
“Yeah, but it's gonna fuck up a lot of other people,” Fleck replied. He pushed the mike button. “Control to operators! If you unlock a door, prop it open. Repeat -- prop all locked doors open!” The supervisor laid the mike aside. “Wendell, where we at on level?”
“142.”
“How fast we losing it?”
Wendell did a quick mental calculation. “Maybe … six inches a minute.” As expected, the level had instantly dropped three feet from the scram when the water inside the vessel had ceased its intense bubbling. But since then, the height of the water above the core had continued to lessen due to the boiling away of steam being created by the heat still remaining in the fuel bundles.
“Starting STurDI-1!” the chief operator announced.
Wendell looked toward the controls. Come on…
“No go!” the chief operator reported. “Startup pump didn't even come on!”
Shit. We've gotta get some water in! The reactor vessel was sealed off from the rest of the plant, the valves on the steam lines having slammed shut when offsite power had vanished. To remove the steam still slowly building up inside the huge steel container, pressure relief valves were now periodically venting the hot gas into the torus. That automatic system was working as designed to keep pressure in the vessel at a safe level. But the crew at Fairview Station had no way to replace the steam removed by the P.R.V.s with fresh water.
“Control!” the speaker crackled. “This is DeMira.” It was the turbine building operator. “I'm at the #1 diesel. Had to unlock the door. Ready to try a local start.”
Fleck glanced at the assistant operator manning the diesel generator panel. “Go!” the operator said.
The senior shift supervisor stared at the floor, thinking. “Any alarms on the local panels?” Fleck asked into the mike.
“Negative on alarms,” the man in the diesel room responded. “Black board. Over.”
“Try local start,” Fleck ordered.
“Trying local start.”
A few seconds passed. Wendell bit into his lip. Jesus, please.
“I'm not seeing anything!” the assistant operator reported from the diesel panel. “No R.P.M.s! Nothing!”
Wendell frowned. How?...
“Control,” the radio confirmed, “no diesel start. It didn't turn over.”
“Damn,” Fleck murmured. “Not that easy.” He spoke into the mike. “We copy. Go to full manual override. Over.”
“Roger. It's dark in here. Hang on.”
Fleck released the mike. “Damn it, I should have kept Zabowski headed there to help.” He looked at Wendell. “How long before the next venting?”
“Maybe a minute.” The torus would soon receive more excess steam when a P.R.V. again opened.
“What's torus temp?”
“About 105. Not too bad.”
“Drywell?”
“230 and still rising. Getting hot in there.” Too hot. Christ. The drywell cooling system was without power, and heat from the reactor vessel was now raising the air temperature inside the cavity. The concrete and steel shell could withstand up to 300 degrees. Above that, it would begin to weaken.
“Control! DeMira!” the man at the diesel generator called over the radio.
Wendell looked hopefully toward the assistant operator at the diesel panel, but his face had only soured further.
“No go!” reported the voice on the speaker. “I tried three times. Air's okay, but it won't keep rolling.”
“God damn,” Fleck muttered. “All right, take a look around. We need that diesel.” He put the microphone aside and shook his head. “We better get something working soon.”
FIGURE 5 (
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“Why won't it start!” the chief operator cursed beside the STurDI-2 controls. “I ran the test last week. It worked perfect!”
Wendell looked up through the glass at the outburst as he continued on the phone. They were six minutes into the event, and the load dispatcher had to be made to understand. “We need it bad here. Bad. Do anything you have too. Temporary fix. Re-route shit. Anything! But we need power back. Otherwise, we're gonna have a fucking mess on our hands! What?... Good. Whatever it takes. Just soon!”
Back in the control room, Wendell found the two operators still at work on the broken safety systems, while the STA stood between them at the center panel, monitoring the conditions in the vessel. An alarm went off and was quieted within seconds. In the rear of the room, Fleck was using a pocket flashlight to scan an emergency procedure. “The L.D. says our primary supply is down a few miles from here,” Wendell told him, “just like the backup. They're trying to get crews on it, but it's gonna be awhile. He thought ninety minutes.”
Fleck looked up, his normally placid features now hardened. “We haven't got ninety minutes.”
“I told them. They got the picture.” Christ, I sounded desperate enough.
“Darrel!” the chief operator said. “I'm gonna start checking fuses.”
“Right.”
The operator dropped to his knees and removed the lower door of the STurDI-1 panel. An alarm went off, and he checked the flashing annunciator, then slapped at a nearby button. The horn ceased.
“Control! DeMira!” It was the man in the diesel room.
The assistant operator stepped away from the diesel panel and picked up the radio mike. With his counterpart he began discussing what to try next to get the huge engine started.
Wendell moved to the center panel. “Tom, where we at on level?”
“122,” the STA said. There was ten feet of water over the core -- six feet less than normal.
“Drywell air temp?”
“255. It's on a slow rise.”
Jesus. If that keeps going up, we'll need to act. What else to check? What else could go wrong? ... A radiation leak? Could we detect it? “Rad meters?” Wendell asked
“The working ones show normal,” the STA said.
“Which ones? How much coverage we got?” Only battery-powered instruments were still in operation.
“Could be worse,” the STA said. “We’ve got drywell, torus, a few in the reactor building. We'd catch anything big, I think.”
“Good.”
Wendell heard the assistant operator at the radio looking for an answer. “All the racks okay?”
“Yeah,” the speaker crackled. “All normal.”
“Shit. There's gotta be a reason. What the hell's happening?”
Wendell frowned. Good question.
------
Wendell paced near the panels. How do we get some power back? How do we get water in the vessel? Neither STurDI-1 or STurDI-2 were working, and they needed the diesel generator to run VEPI or fuel spray.
“Okay, try the bypass line,” the assistant operator ordered the man in the diesel room.
“Control!” A different voice came from the radio speaker.
“Control. Go ahead.”
“This is Zabowski,” the breathless voice said. “I just got out of STurDI-1. It's a mess! The Startup oil pump broke away and spewed oil. Nothing I can do. Phone down there don't work either. And the radio won't carry till I get up the stairs.”
The chief operator crawled out from working beneath the STurDI panel. “Let me talk to him.”
Wendell stopped his pacing and listened. At the center panel, the STA turned, and Fleck left the procedure books on the back table and came closer. The attention of all five men in the control room was centered on the radio as the chief operator took the mike. “Zabowski, this is Larry. Broken oil line on SturDI-1?”
“Roger, right by the pump.”
“Okay. Get down to STurDI-2 . It's not responding at all. Check the control box. The fuses, switches, wiring, whatever. The start signal's not getting there.”
“Roger. Out.”
The chief operator turned to Fleck, his face drawn tight. “Unless he finds something, we're screwed. You heard what he said about STurDI-1.”
“Yeah, oil everywhere,” Fleck said. He looked to the assistant operator. “The diesel? You tried all the bypasses?”
“Yep. Nothing.”
“Damn,” Fleck sighed. Well, keep trying. Tom,” he asked the STA, “what’s our level?”
“113 inches.”
Wendell cringed at the number. I've heard figures like that a hundred times in the simulator -- but this is for real.
“Drywell temp?” Fleck said.
“260.”
Wendell turned to Fleck. “Sounds like it's leveling off. It was near that a couple of minutes ago.”
“It's not screaming up like it was,” the STA agreed.
“Control!” the radio speaker blared yet again. The assistant operator took the call, which came from the diesel room.
Wendell and Fleck conferred. “I'll hit the Emergency Procedures and figure out the Action Level,” Wendell said.
“Yeah,” Fleck nodded. “Probably a Site Emergency. Call out the troops.
And I'll talk to Borden.”
Wendell headed for the office as Fleck addressed the STA: “Tom, get Leeman on the phone. Tell him I want some people out here right now. Mechanics, electricians, I & C, the works. Then get Cervantes.”
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End Post 24
+++++++++++++++++++++++++++++++++++++++++++++
TEASER FROM NEXT POST:
“Steve, this is Darrel Fleck. We have a major problem here. We’ve got a station blackout with no makeup to the vessel.”
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posted by James Aach @
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