Chuck whipped his head toward the sound of the rumble just in time to see a puff of salt dust billow into the corridor.

“Not tonight,” he groaned. “Not again.”

He threw the transport into reverse and backed up three hundred feet to the entrance of Room 6 in Panel 5 of the Department of Energy’s Waste Isolation Pilot Plant. Mined out of salt beds 2,150 feet beneath the New Mexico desert, WIPP’s expansive system of rooms and corridors provided permanent protection from some of the nation’s most dangerous radioactive waste.

The transport skidded to a stop, kicking up another puff of salt. Chuck shined his light deep into the room. Darkness devoured the beam. He rocked back and forth, nervously considering options.

“Shit. Shit. Shit.”

Nobody was around. Of course not. Nobody was supposed to be in the underground at this hour—and never alone.

Twenty minutes earlier, the night safety coordinator had his feet on the desk and earbuds delivering country music. Swinging his lanyard to the beat of Hardy, he noticed his radiation monitoring badge, usually connected to the lanyard, was missing. A quick check of the office confirmed his fear. He left the dosimeter underground while inventorying hardhats and miner’s lamps for decontamination after the day’s entry. Already on thin ice with management, he sure as hell wasn’t going to self-report a lost dosimeter.

The rocking slowed. The smart choice would be to leave. Erase all evidence he had been in the hole, and let the dayshift figure out what happened. But maybe the rumble could work in his favor. If it was another ceiling collapse, he could report it to Mel discreetly. Give the boss a chance to fix the paperwork. Maybe then Mel would finally stop ragging on him for misplacing a fifty-five-gallon steel drum of radioactive waste last month. With hundreds of drums shipped to WIPP weekly, one was bound to be misplaced once in a while.

Chuck stepped from the transport and looked both ways down the long empty corridor. Though he had spent much of his life hunting and hiking by himself in the desert, he never felt so alone. At the wide entrance to Room 6, a precision cut in the solid salt wall two feet thick from floor to ceiling, he strained to see inside. Darkness.

The clipboard on the wall provided no indication a collapse was expected, but it had to be a ceiling collapse. With nobody working the late shift and nothing living in the underground, a collapse was the only explanation for the rumble and puff of salt dust.

Small blocks of salt fell from the ceiling once or twice a year causing more of an inconvenience than a problem, but since the fires of 2014, salt creep was supposed to be monitored more closely. Collapses were to be predicted, identified on the room inventory sheet, and, of course, immediately reported to the Department of Energy, the government agency responsible for WIPP.

Another glance at the clipboard.

“Shit.”

The last thing he wanted to do was enter Room 6 alone. Waste drums in that room had been nothing but trouble. Mel had ordered everyone to stay out unless he approved the entry. But something else was keeping him from zipping in to check it out. There were rumors about Room 6.

He maneuvered the transport to face the entrance. Dim headlamps on the electric vehicle lit the room wall to wall but struggled to project deep into the waste tomb. The collapse could be anywhere. He sucked a deep breath through the respirator, squeezed the steering wheel tight, and crept toward the drums against the back wall. The nearly silent electric motor of the dual-seat transport seemed to amplify the sound of salt crunching under the tires. Two hundred sixty feet into the room, he lifted his boot from the accelerator. The transport stopped with a lurch.

“What the hell?”

He wiped a sleeve across the plastic facemask of his respirator.

“No freakin’ way.”

Forty feet ahead, a pair of eyes glared at him over the top of a fifty-five-gallon steel drum. Cobalt-blue eyes reflected the dim headlamp.

He shook his head, ripped off the respirator, and rubbed his eyes clear.

“Not possible.”

Muffled sounds of gnashing, chomping, and slurping permeated the room. A second pair of eyes joined the first.

Crack!

The chomping stopped.

Chuck’s eyes darted upward in time to see salt crystals dribble from a narrow crevice in the ceiling. He slammed his foot on the pedal, swung the transport around, and fishtailed into the corridor, speeding toward the elevator.

“Come on! Come on! Faster, damn it. Faster!”

Panel 5, the farthest panel from the elevator, and Room 6, the second-to-last room in the panel, made the drive in the electric cart almost a mile. A quick look over his shoulder. Obscured in a trail of salt dust, something was following. Halfway to the elevator, radiation alarms began to wail. Sirens blared in the corridor. Red strobe lights bounced off white walls.

“I’m fired. I’m fired. I’m fired.”

He hadn’t had that much to drink. Not enough to be seeing things. Nothing lived in the underground. With no outside access, no food supply, and no water, nothing could survive in WIPP.

A cadence of galloping feet overcame the high-pitched whine of the motor. He pushed harder on the pedal, already pasted to the floorboard. His respirator slid off the seat as the transport skidded through the turn into the main corridor. Though every fiber in his body was telling him not to, he had to look again.

“Shit!”

Two very large somethings were catching up fast.

“Be there. Oh, God, please be there.”

He hurled himself from the transport, tumbled once, and came to his feet, hitting the elevator call button in stride.

“Open. Open. Open.”

Inside the conveyance, he pounded the ground button.

“Close! Close! Aaaaaaagh!”