Of course, some motion had to be tolerable: what if the air-conditioning caused a curtain near the bomb to ripple? So the detector calculated the amplitude of change over time. Any change that was strong—or long in duration—would set it off, the exact definition of “strong” or “long” having been preset in the detector.
Also, as Payne knew, you could beat a microwave sensor if you knew how. There were ways. If you approached the sensor very slowly, you might not set it off.
But if you allowed your arms to swing at your sides even slightly, you’d probably get nailed, because your arms would be moving toward and away from the sensor at a greater rate of speed, a greater rate of change, than the rest of your body.
That wasn’t even a possibility now, however. Without seeing the bomb and being able to estimate its distance from where they were standing, they certainly could not risk approaching it.
And here was the bitch of it. How could you kill a bomb when you didn’t even know where it was?
CHAPTER NINETY-FIVE
Within fifteen minutes, the line of evacuees from the Network building dwindled and then stopped. Another announcement was made over the PA system, but ten minutes later no one had emerged.
None of the workers who had filed out of the building bore a remote resemblance to Baumann.
* * *
Inside the building, Sarah made her way up the stairwell. She had searched the first four floors, but no Baumann. And no Jared.
On the fifth floor, she walked silently down the empty corridor, checking office after office.
* * *
Dr. Payne made a swift calculation.
They were detecting microwave energy, but did that really mean they couldn’t move? He knew that the range of detection is always greater than the range of function—that is, they could “see” the microwave emitter, but the emitter couldn’t necessarily see them. There’s always a threshold of acceptable leakage, just as a microwave oven might leak microwaves, but people don’t necessarily get cooked standing in front of it.
Payne had examined the fusing system. He knew now how much energy it needed to set off the bomb. The more he repeated his mental calculations, the more sure he was that the amount of microwave energy leaking under the steel door was not enough, if reflected backward, to trigger the detector.
They were safe where they were. They could move.
* * *
“All right,” Dr. Payne said. “The safe line is on the other side of the door. There’s some stray microwave leakage, but we’re safe as long as we stay on this side. Everyone, back off from the door. You, Grant, and you, O’Hara”—he pointed at the DOE scientist who had lost it—“get out of here. I don’t want to see you again.”
On this side of the door, on this side of the safe line, they could move. The microwave sensor, he now realized, would detect motion on the other side of the door only.
This was good. This gave them considerably more room to maneuver.
This also meant they could remotely “look” at the bomb using a technology that remains to this day highly classified by the U.S. government. They used a device called a neutron backscatter, which emits a stream of neutrons at a very specific energy level. The stream is fired at the target, and then the backscatter measures the rate at which the neutrons come back at it—that is, the extent to which the neutrons are absorbed.
The neutron backscatter has the ability to penetrate metal liners and walls, so the steel door was not an obstacle. Using the same physical principle employed in an HED—a hydrogenous explosives detector—it looks for hydrogen. The neutron backscatter they were using was unusually powerful. Payne flipped the switch, checked the readout.
“Well, there’s explosive material there,” Dr. Payne muttered to Suarez. “A shitload of it, from what I can tell.”
“Now what do we do?” Suarez asked.
Dr. Payne did not reply; the truth was, he had no idea. He was winging it; in times like this you always had to wing it and trust your instincts.
“All right,” he said at last. “I want the generator moved out here.”
“You want to do what?” asked Suarez.
“Like I said,” Dr. Payne said. “The generator.”
“You want to do the EMP? Jesus—”
“I want to burn out its solid-state mind, and I don’t even know if that’s going to do it.”
The electromagnetic-pulse generator was powered by a huge capacitor, really a bank of capacitors that required an immense power source. As the capacitor was wheeled into place beside the steel door to the basement, Lieutenant Colonel Suarez said, “Sir, with everyone out of the building, the situation is no longer life-threatening. Textbook says we’re not supposed to risk our lives if the situation’s not life-threatening. And the building’s empty.”
“Except for the terrorist.”
“Except for the terrorist, yes, sir.”
“The terrorist, and a child. And if this building goes up, those aren’t going to be the only ones killed.”
“Sir, the textbook—”
“Fuck the textbook,” Dr. Payne said. “Get the door open.”
“Sir, we can’t,” Suarez said.
“Well, we can’t shoot through the goddam thing! We can’t aim the EMP unless the door’s open. Get the goddam door open! Now!”
“It’s locked, sir.” Suarez was doing his best to keep his cool. “We can’t use explosive breaching techniques, sir. You don’t breach the door of a magazine.”
“Dammit,” Dr. Payne said, “get out the halligan tool.” This was a standard piece of equipment used to force open doors.
“Bad idea, sir. Respectfully. Looks like the door lock has been jammed with epoxy or Krazy Glue or something. It opens outward, toward us. It has to be opened from inside. Gently. But it looks as if it can be opened from the inside.”
“If we force it…” Payne mused aloud.
“If we force it, we’re introducing a violent motion, and you don’t want to introduce energy into a bomb situation, right? If we use a halligan, we could set the thing off.”
“Shit. You’re right, Suarez. Good thinking. All right, do we have anyone already inside the building?”
“I don’t know—”
Dr. Payne picked up his walkie-talkie and, calculating that it was safe to broadcast on this frequency, called Lieutenant George Roth. “Do we have anyone already in the building?” he repeated.
* * *
Sarah turned in the empty corridor.
Suddenly there was a static squawk.
It was her walkie-talkie, coming to life.
“Cahill, Cahill, ERCP,” came a flat, mechanical voice. ERCP referred to “Emergency Response Command Post,” the label NEST was using to avoid alerting any reporters who might be listening in.
“ERCP, Cahill, go ahead.”
“There’s a back way into the basement. We need you to enter the basement and open a door for us.”
CHAPTER NINETY-SIX
Fueled by anger and determination and fear, Sarah ran down to the lobby and, in a dim corner, just as the floor plans had indicated, located the little-used basement door.
It was jammed shut from the outside, the lock plugged with the broken end of a key and some Krazy Glue. Baumann clearly didn’t want anyone to enter the basement.
The door couldn’t be forced. That might set off the bomb.
There had to be another way to get into the basement.
Desperate, she ran across the lobby. How could she get into the basement without using the doors?
She passed a maintenance closet that had been propped open by a galvanized steel bucket and wet mop. She stopped, opened the closet door all the way, and saw the pipes at the back, running vertically up and down through the building.
The answer.
They ran through a shaft, roughly two feet square, into the basement. There was space in front of the pipes, not a hell of a lot but perhaps enough.
She leaned over and peere
d down the shaft.
The drop to the basement floor was probably eight or nine feet. Several of the pipes made sharp right angles into a wide, dull gray, steel ventilation duct. The duct was some four feet wide. Wide enough to shield her movements from the microwave detector.
She pulled off her shoes and her jacket and squeezed into the narrow space, grabbing on to the pipes as she moved. It was a tight squeeze, but she realized quickly she could make it through.
It was like crawling through the narrow neck of a cave.
She shimmied down, holding on to the pipes, lowering herself as much as she could toward the floor of the basement. Then the pipes veered off at sharp angles in different directions. A drop of some six feet remained.
She eased herself down slowly, carefully. Shielded by the duct she dropped noiselessly to the ground.
She gasped when she almost stumbled over the body of a uniformed man, crumpled on the floor in front of her. It looked like a security guard, probably someone who had tried to stop Baumann.
She spotted a long stack of boxes roped together, on top of which sat a small black box, which flashed in the sputtering fluorescent light.
If you can see it, it can see you, Dr. Payne had said.
But from how far?
Estimating distances didn’t come naturally to her, but she had learned to do it, and she now calculated she was ninety to one hundred feet from the device.
She stopped, pressed the transmit button on her walkie-talkie. “ERCP, ERCP, Cahill,” she said. “I’m here. I see it. How much time is remaining?”
“Cahill, ERCP. We don’t know,” Payne said. “We figure that as long as the terrorist is in the building, it’s not going to blow.”
“Good.”
“Uh, Agent Cahill, I wouldn’t be so relieved if I were you. The device has got a ground-plane antenna protecting a circular area, with a possible operating range of forty to sixty feet. If you’re beyond sixty feet from it, you’re safe. Now, I want you to move forward slowly.”
“How slowly?”
“I can’t answer that. If you’re far away from it, any movement will be perceived by the sensor as much slower than if you were right up next to it.”
“Give me a rate of speed!”
“As slowly as you possibly can. Recognizing that we’re all under the gun—there’s got to be a clock ticking, but we just don’t know when zero hour is. Let’s say slower than one step per second. We estimate the sensor can ‘see’ someone walking at the rate of one step per second, so keep it slower than that.”
“Jesus, that’s slow!”
“Keep your arms against your side. No, better—keep your arms folded against your chest. Whatever you do, you must not allow your arms to swing. The microwave’s going to see a rapid fore-and-aft like a champ. You want to avoid creating a Doppler shift.”
“Meaning what?” She knew bombs, but not to this degree.
“Just … just keep your body as still as possible. Keep flat against the wall. Inch along it. A few inches a second, no faster. Now, whenever possible, keep solid objects between you and the bomb—the furnace, machinery, whatever’s down there. Anything RF-opaque. According to our examination of the device, it’s a bit above ten thousand megahertz, so bricks and dense masonry like concrete and steel will be pretty effective at blocking it.”
Sarah inched toward the main basement area, then stopped. She raised the walkie-talkie to her mouth, realizing that this was probably the last time she’d be able to use the walkie-talkie as long as she was down here: from now on, she’d have to keep her arms folded.
“There are some large objects,” she said. “A water heater. A row of something. But there are gaps between them. Huge gaps. I’m not going to be able to always keep solid objects between the bomb and me.”
“Do your best,” Payne instructed. “In the gaps, be sure to move as slowly as possible. This is a volumetric device.”
“Meaning—?”
“Forget it. You must not change the reflected patterns of the microwave. It sees rate of change. You’ve got to minimize your effect on the rate of change of the energy pattern by minimizing your body motion.”
“I don’t know what the hell you’re talking about!”
“Move very slowly and steadily, Agent Cahill. And go!”
Oh, dear God, she thought. Sweet Jesus God.
Jared was in the building, had to be in the building, upstairs. She could not think that he was dead. He was alive, he had to be alive, but silenced somehow.
An FBI agent could, under some circumstances, be called upon to sacrifice his or her own life. But not the lives of their loved ones. That was not in the employment contract.
Now as she inched along the cold damp basement wall she felt a waft of ice-cold air and smelled the old familiar dirt smell of mold, a smell she associated with her childhood, and therefore found oddly reassuring.
One … two … one … two. A slow-motion side-shuffle. Her hands gripping her chest, flattening her breasts. One … two … one … two. Her legs trembled with the enormous exertion it required to keep them from jerking away from her. Brushing against the cold damp wall, one, two …
… Up to the water heater, a behemoth, floor-to-ceiling, wall of steel, blasting heat, pilot light twinkling. Easily eight or ten feet long. She reached it, recoiling from the overpowering heat, exhaled.
It bought her ten feet, she thought. Ten free feet. She slid against the wall, quickly now. She felt a prickly flush of heat, and the sweat began to run down her arms, down the inside of her arms, down her breasts, tickling her. Rivulets of sweat ran down her inner thighs. Fluorescent light flickered sickly greenish-white.
She came to the end of the heater, and there was a gap, a space of another five or six feet, before the next shelter, which she now saw was long and rectangular, a tall row of filing cabinets.
Immediately she slowed her pace, inched along. As she edged, she stared at the black box, her eyes glistening with fear, feeling as if the invisible microwaves could feel her, were invading her body, arrogant and intrusive and everywhere. Now, from this angle, she could see a tiny pinpoint of light, a ruby-red dot, on top of the black box. What was it, an indicator? Would it wink at her if it caught her moving? Would it wink in the split second before the building was incinerated, turning her and her little boy into ash? Or would there be no warning at all? Would she move a few inches per second too quickly, enraging the red-eyed monster, and never know anything?
She stared, and she thought about Jared, and she began to formulate a plan, anything to distract her, send her mind elsewhere, anywhere, while she edged along the dank wall to the file cabinets, light flickering fluorescent-green.
Another twenty-five feet to go, and then she would have to move along another wall before she reached the door.
Hugging her chest harder, her clothes soaked through.
Thinking of Jared, cowering in a room somewhere.
She glided along the wall behind the filing cabinets, mindful of the gaps between the cabinets, through which the microwaves could pass. She had to move slowly here too, just as slowly, because of the gaps. Then she came to another open space. This one seemed miles long, seemed to stretch an eternity. Inched now. A muscle twitched, something connecting hip to leg, a slight jerking motion, and she froze. Her heart knocked against her rib cage. Stood still, holding her breath. Waiting for the ruby-red light to wink at her. It didn’t. She exhaled slowly. Moved again to her left. One … two … one … two …
Could hear voices on the other side of the heavy steel door, which was coming closer inch by inch. The NEST men issuing and receiving instructions, setting up their machinery, waiting for her to ease open the door. Her walkie-talkie crackled; she ignored it.
“Cahill, Cahill, ERCP, are you there yet?”
Her arms glued to her breasts, she inched, inched, not answering. Sidled up to the next RF-opaque obstruction, which seemed to be ductwork, but this one was narrow, maybe five feet of relief, wh
ich was nothing.
She thought of Brian/Baumann. Flashed on the Identi-Kit sketch, which was a bad cartoon, looked nothing like the real thing. What did Baumann really look like? Did she know? Who was he? She inched along in the next open space, and now she felt the snugness of the corner, cold and damp and pleasantly rounded.
Negotiating this turn was not easy. She swiveled in slow motion, trying to understand the physics of the microwave sensor.
Stared at the unwinking tiny red dot.
Sidled, inch by inch by inch. Hugging herself tighter and tighter. Felt a tickle in her throat. Had to cough. Now it was all she could think about—don’t cough, coughing will cause your head to jerk. The tickle was unbearable.
She inched along; the tickle subsided.
Now the door was close enough to reach out and touch, and it took all of her willpower to keep from doing it. Must keep her arms folded. Must move slowly, inch by inch.
How far was she, how far was the door from the bomb?
Never good at estimating distance, and never was it so important. Fifty? No, more. Sixty? Maybe. Sixty was the cut-off. Within sixty feet, the sensor could read movement. A little more, perhaps. Sixty-five feet?
Hard to know.
Yes. Sixty-five feet.
Voices on the other side of the door grew louder.
Until she had reached the doorframe, sidled her body along until she stood directly in front of the door, and she slowly, slowly eased her hands down, as if caressing her breast, her abdomen, her hips, straightening them, moving them along the contours of her body agonizingly slowly, until both hands grasped the steel doorknob and she turned it, and it didn’t move, and she turned harder, and still it didn’t move, and then a twist of both hands and the knob turned. The door had been jammed so that it couldn’t be opened from the outside, yes, but inside it could be opened, thank God, and, yes, it opened out, not into the room, thank God.
“I’m there,” she said.
The Zero Hour Page 40