The Coolant Rupture

How many tons of pressurized butane did it take to vaporize four city blocks?

Pelagia slammed her palms against the brass manifold casing of Control Console Four, her grease-slicked fingers catching on the emergency trip valve. On the seismic telemetry board before her, four red warning needles danced against their brass stops. The primary catalytic cracking tower three miles north was already a burning husk, but the feedback loop was tearing through the secondary conduits beneath the Halikarnas refinery complex like a subterranean fire.

"Solenoid six is gone," she muttered into the dead air of the reinforced concrete blockhouse, glancing grimly at the framed Directorate quarterly valve inspection certificate hanging crooked beside the dial. "So much for flawless third-quarter compliance. Compressor bay three is venting raw methane. And someone just ran four hundred tons of armored locomotive past the outer perimeter gate."

Through the eight-inch laminated quartz observation slit, the switching yard looked like an abattoir bathed in sodium flare light. Thick sulfurous smoke billowed between the towering distillation columns. Below, on the high-speed transit line of Track Two, the black silhouette of Locomotive 404 thundered forward, throwing showers of orange sparks from its locked iron wheelsets. It was hurtling at forty miles an hour directly toward Junction Six—where twelve linked butane tankers sat dead on a spiked siding.

Pelagia snatched the Bakelite receiver of the emergency yard radio from its magnetic cradle. She cranked the induction dynamo three sharp turns until the dyno-whine peaked.

"Locomotive 404, kill your throttle and dump the tender emergency cock," Pelagia barked into the mesh grill. "You're running straight into the butane battery at Junction Six. The switch points are wedged shut."

Static crackled across the speaker horn overhead. A dry, rasping voice cut through the hum of the dyno.

"Brakes are severed, engineer," Stathios replied from the cab, his voice competing with the roar of an overloaded diesel turbocharger. "Auxiliary lines were cut clean before we cleared Siding Two. If I drop reverse now, we'll strip the drive gears and jump the frog."

"Stathios?" Pelagia stared at the glowing track diagram. "Who authorized you on Track Two?"

"A woman with a fifty-caliber rifle and an investigator who claims the whole yard is poisoned," Stathios shouted back over the radio. "Give us an open rail or we're turning your butane battery into a crater."

Pelagia pulled down the heavy steel handle of the pneumatic system bypass. The copper needle on the main receiver dropped ten pounds, but the green tally lamp for Junction Six remained dark. The track solenoid was wedged fast by a mechanical obstruction.

"The switch points are spiked with iron," Pelagia said, her voice dropping into the flat, cold register she used during tier-one plant failures. "Listen to me carefully, yardmaster. Two hundred yards before the junction, you pass the cryogenic coolant transfer gantry. There is an emergency knuckle release lever on the tender platform."

"I know the lever," Stathios grunted. "Manual drop pin. It takes a sledgehammer or forty foot-pounds of torque to yank it under draft load."

"Then find someone with strong arms," Pelagia ordered. "You have to decouple the three trailing cryogenic tank cars now. If you shed sixty percent of your trailing mass before the curve, your engine's dynamic retarder can take the switch into the Maintenance Loop Twelve without flipping the tender."

"What about the switch?" another voice broke in over the frequency—sharp, younger, clipped with Directorate diction. "If the points are spiked, the engine will still hit the chemical yard."

"I am going to blow the high-pressure steam purge through the pneumatic conduit," Pelagia said, reaching for the master boiler override wheel behind her console. "Three hundred pounds of superheated steam will shatter the cylinder housing and violently blow the spikes out of the points. But I only get one burst. When I trip the steam valve, you pull that knuckle pin."

Behind the armored cab of 404, visible through her quartz viewing slit, a dark figure in a long coat scrambled onto the violent gap between the diesel tender and the trailing cars. Damathea braced her boots against the vibrating steel grating, driving the butt of her heavy rifle down onto the locking dog of the coupler pin.

Pelagia gripped the iron handwheel of the high-pressure steam line. Her shoulder muscles burned as she torqued the rusted valve open.

Three hundred pounds of superheated steam slammed through the underground pneumatic lines. Across the yard, iron pipes shrieked in agony. At Junction Six, a violent cloud of white vapor exploded from the pneumatic switch housing. The rusted iron piston gave a deafening metallic crack and rammed the switch rails three inches to the left, lining the points into the banked curve of Maintenance Loop Twelve.

"Pin is loose!" Stathios yelled through the radio horn. "Coupler clear!"

The three trailing tank cars detached with a monstrous metallic shriek. Relieved of three hundred tons of dead weight, Locomotive 404 lurched forward, its diesel prime mover screaming as Stathios threw the traction motors into emergency regenerative braking. The engine leaned hard into the curve, wheels throwing blinding sheets of blue friction sparks, before screeching safely onto the reinforced ballast of Loop Twelve.

Behind it, as the steam-thrown switch points buckled under the violent crossing, the severed cryogenic tankers hit the half-shifted rail frog. The leading wheelset picked the flange, throwing all three cars violently off the rails into a tumbling, grinding roll across the wide drainage ditch and gravel embankment. They ground to a crushed stop fifty yards short of the chemical marshaling yard.

Pelagia let her breath escape in a ragged shudder. The butane battery remained untouched.

Then the seismic needles on Console Four spiked violently.

From the shadow of the transfer gantry, a massive bulk tore through the corrugated steel siding of the compressor hall. The Tar-Stalker was four times the size of a draft horse, its torso an undulating mass of glistening, pitch-black bitumen and reinforced carbon plates. It galloped on six asymmetrical, clawed limbs, drinking the pooling diesel run-off from the ruptured yard fuel lines.

The beast lifted its eyeless, wedge-shaped head, scenting the air. It turned toward the maintenance loop, accelerating toward the rear of the decelerating locomotive with terrifying speed.

As it lunged across the track bed, its massive, armored shoulder struck the exposed overhead cryogenic manifold—a six-inch insulated conduit carrying liquid nitrogen from the refinery's air separation unit to the storage spheres.

The high-pressure flange sheared clean off.

A torrential plume of liquid nitrogen, boiling instantly at minus three hundred and twenty degrees, engulfed the charging monster.

Pelagia pressed her face against the quartz slit.

The Tar-Stalker did not burn or ignite. Instead, the thick, undulating layers of petroleum flesh froze instantly into white, glass-like frost. The creature let out a high-pitched, crystalline shriek as its fluid musculature vitrified into a brittle solid state. Its forward momentum carried it into a concrete stanchion.

Upon impact, the frozen beast did not bleed. It shattered.

Tons of petrified black tar burst into millions of glittering, brittle shards that clattered across the gravel like broken windshield glass.

Pelagia stared at the glittering pile of slag, her hand gripping the edge of the brass desk. The beasts could drink burning diesel and shrug off heavy gunfire, but extreme thermal shock instantly fractured their hydrocarbon lattice.

She grabbed the radio microphone, keying the line with an unsteady thumb.

"Stathios," she whispered, her voice tightening. "Did you see that?"

"We felt the shockwave," Stathios answered, the cab's engine idling low in the maintenance bay. "What did you hit it with?"

"Liquid nitrogen," Pelagia said, her eyes fixed on the telemetry boards as fresh telemetry lines began to flicker across the city map. "Cryogenic coolant. Their organic oil structure can't handle extreme negative temperatures. It turns them to brittle glass."

"We've got five cryogenic tanker cars parked in the cold siding behind Bay Four," Kyriakos's voice crackled through the speaker. "Pelagia, can we load them from the secondary storage tanks?"

"The secondary tanks are full, but that's not our biggest problem," Pelagia said, watching the refinery's district-wide seismic grid.

Dozens of deep acoustic vibrations were registering along the southern industrial corridor. The red pins on the electronic map were no longer scattering randomly through the rail sidings. They were aligning in a single, massive vector, marching shoulder-to-shoulder along the heavy pipeline rights-of-way.

"They're moving," Damathea's cold voice came over the speaker. "Where are they heading?"

Pelagia leaned over the plotting table, her fingers tracing the glowing arterial line where two million gallons of pressurized fuel waited beneath the city.

"They're not feeding on the spills anymore," Pelagia said, the words heavy and cold in the quiet bunker. "The whole pack is migrating directly toward the central pressurized LNG depot."