chief muttered as his eyes shifted along the arrayof scopes on the panel, "I see that, but why aren't we getting anyhead pressure?"

  The board men continued to run new series of response checks on therest of the pump system. Outside, the head of the heavy equipmentconvoy came to a halt and the crews climbed out to wait beside theirvehicles.

  Five minutes later the board men finished their checks and thenconferred briefly with the section chief. He came over to theengineers.

  "I think we've got your answer," he said glumly, "but I don't thinkyou're going to like it. The best we can figure out is that the shockmust have created some kind of a lag turbulence down there and when itwas over the water piled into Number Four and slammed it over on itsside. Or maybe the shock just tipped it over. In any case, it's eitherclogged the intake or jammed the nozzles. We don't know which. Andit's jammed the dampers."

  "So," the hydraulics chief shrugged, "we put another unit down there."

  "It's not that simple, Mr. Hall," the monitor chief continued. "Thatpile's running wide open and no place to go. It's got to be stopped orshe'll blow right outta there. And if Four goes--blooey, there go theother three."

  The chief engineer sagged. "No chance of getting the dampers torespond?"

  The monitor man shook his head sadly.

  Hall ran his hand tiredly over his face and stared silently at theflickering oscilloscopes as if to force the damping device intofunctioning by sheer will power.

  He sighed and straightened up. "All right," he said, "how do we shutit off. Is there an outer manual system?"

  "There is," the monitor chief replied, "but in all likelihood it'sjammed, too, by the shock or tip-over--and I'm more inclined to buythe tip-over than anything else."

  "Any other way to shut it down?" Hall queried.

  "Just one," the chief said. "Blow her apart chemically before she goescritical. And that, chief, is a real tough one. Someone's got to godown there and clamp some plastic blocks in the right place on thepile housing. Even then, there's the chance that she might blow in thewrong direction and the whole shebang will go up in big, fat mushroomcloud."

  Hall's eyes saddened. "If that's it," he sighed, "that's the way ithas to be. Let's get with it. Where does the plastic go?"

  "Better check that out with Barton in the main rig," the monitor chiefreplied. "He's got the prints and he can show you the exact spot onone of the spare pumps. Oh, and Mr. Hall," he paused, "you'd betterhurry it up. She's leaking a little of the pressure down there butnot nearly enough. I'd make a quick guess and say that we've got lessthan two hours to either shut that pile down or relieve the pressure.And if she's tipped, the time in getting it back up and checking outdamage on the pump system is going to take too long and it might notbe repairable. The best bet is to blow her."

  Hall nodded and with Harbrace and the junior engineers in his wakewent to the central pump section vehicle.

  Walking to the other vehicle, Alec looked at the water with strickeneyes. "God in Heaven," he said aloud, "I never thought it would endthis way."

  Harbrace broke stride and took Patterson gently by the arm.

  "None of us did, Alec," he said. "This isn't your fault. You had afine idea and it worked. What happened afterwards is no worse than theoriginal quake that caused the damage. If this thing blows out, wewon't be out any more water than we would have been if you hadn't comeup with the idea in the first place."

  "That's not what I meant," Alec said in a shaken voice. "If this doesblow out, not only do we lose the water but we're going to contaminatethis aquifer with radioactivity from here to the mouth of theColumbia."

  "I know that, too," Harbrace replied softly. "It's still not yourfault, son. And we're not licked yet. Come on."

  * * * * *

  Twenty minutes later, a double strand of durasteel cable stretchedacross the three-hundred-foot wide current, suspended between theraised crane towers of four of the mammoth crane carriers and passingtwenty feet above the churn of the bore hole.

  Hall and a half dozen of his section chiefs stood at the base of oneof the makeshift towers. The chief hydraulic engineer had a headsetclamped on for contact with all the working units.

  He turned to one of the men standing by. "Get me a pressure reading onthat hole," he ordered. "I want to know how much weight it's going totake to get down through that mess."

  "Why not just shut the other three down while we go down into thehole?" the assistant asked.

  "Calculated risk," Hall said. "If she's going to blow, it isn't goingto make any difference if the others are shut down or not. And, if wecan keep pumping while we're working, we're staying ahead of the flowfrom the reservoir. Get me that reading."

  The pressure report was back in minutes. "It'll take at least afour-ton mass to get down there fast and keep from being buckedaround."

  Hall looked around, "What have we got that's small enough and has thatweight or better?"

  "How about a van tractor?" one of the supervisors suggested. "Theyweigh closer to six tons but they're pretty compact."

  "Fine," Hall snapped. "Rig it."

  The bulky, almost square, tractor was rolled up and the rigging crewswere swarming over it, clamping suspension cables from the runningpulley that would ride the cable across the current.

  "What's the radiation report?" Hall asked monitoring.

  "Still building," came the reply. "But we've got a leak somewhere, Mr.Hall. We're getting readings from the water down there. Not too muchyet, but it may change our time factor. I'd either get on it fast,chief, or let's get outta here. That thing can go any minute now."

  The tractor was rigged. Hall turned and bawled, "Where are thosedivers?"

  Alec Patterson and Troy Braden stepped out of a nearby van, dressed inpressure suits and tanks, their helmet flaps open. Alec had a heavybelt of ultra-high explosive plastic lashed around his midsection.Troy carried a rack of small clamps strung across his shoulders.

  "Where do you think you two are going?" Hall roared. "Get those suitsoff and get outta here."

  "Shut up and listen," Alec snarled. "I started this. I'll finish it.This idiot partner of mine hasn't got any better sense than to goalong. We haven't time to argue, so just listen.

  "Both of us have been trained in hydrology and have made many divesbefore. We've both used this plastic and we've both handled hot stuff,probably more than any of your people. Your man has checked us out onthe pump assembly and we know just what we're looking for. Let's go."

  Hall glared at the pair for a second and then whirled to the riggedtractor. "Get that canopy off that thing," he ordered. "They can rideit down in the seat."

  He turned back to the junior engineers. "Got lights?" They bothindicated a pair of sealed handbeams on their belts. "All right, getaboard."

  "Casey," Hall called over the intercom, "got that communications linerigged?"

  "All set, boss," came the answer. "It will run out the cable and downthe cab. I've left them plenty of slack to move around when they getdown there."

  "O.K.," Hall waved to the riggers, "everybody get outta here. Casey,plug them in."

  Alec and Troy had entered the cab. The communications man leaned overand coupled the phone system into their helmets and then waved atHall.

  "You two hear?" Hall demanded.

  "Loud and clear," Alec replied.

  "All right," Hall ordered, "let's get with it. This is a generalorder. All vehicles and personnel not directly involved, pull back afull mile."

  Men and equipment began moving away.

  "O.K., Number One crane, lift 'em."

  The crane operator on the near bank eased his gears into motion andthe six-ton tractor lifted into the air with Alec and Troy aboard.When it was five feet above the ground, the crane on the oppositeshore began hauling the draw line and the vehicle swung out over thewater.

  "Now listen closely," Hall ordered the pair in the swinging vehicle,"from this point, you are in control. Stop your slide over the hold byjust
yelling "Stop." Number one crane is your up and down operator andalso will pull you towards this bank. If you need to go forward orbackwards when you get inside the hole, just say which way and bothcrane carriers will move in the direction you want. Got it?"

  "Affirmative," Alec replied.

  A second later he yelled