‘The what?’ said Hansen. ‘The caissons?’
‘That’s what Du Bois heard the scientist guy saying to the others,’ said Gallen. ‘But we should ask Mr G-Man here.’
‘Don’t look at me,’ said Aaron, whose forehead shone like that of a man in the middle of an anxiety episode.
‘You don’t have an opinion on that?’ said Gallen, fed up with the secret squirrel act.
‘I have an opinion on how easily these STARs can be reversed into meltdown,’ said Aaron, squirming as they spiralled downwards. ‘These Russian transportable reactors can only be made so small because of their plutonium cores.’
‘Plutonium, as in the warhead material?’ said Gallen.
Aaron nodded. ‘The danger isn’t that you can turn it into a bomb in half an hour. You can’t.’
‘So what then?’ said the Swede.
‘If you can short-circuit the fail-safes, you can put them into meltdown.’
‘Can we use English?’ said Gallen.
‘Ever see that movie The China Syndrome?’
‘Sure,’ said Gallen, searching Aaron’s eyes for clues. ‘The reactor’s cooling system failed and the thing just melts through the floor.’
‘Basically, yes. The plutonium cores feature immense fission activity and so they run at extremely high temperatures unless they’re inhibited and cooled,’ said Aaron. ‘You retard the temperatures with graphite and water and they tick over for a decade at a time before the rods need replacing. They produce steam that drives turbines for power.’
‘And if you fail to retard the fission?’ said Hansen.
‘Like they said in the movie, the rods rise to the temperature of the sun and they simply follow gravity through everything in their path.’
‘And we let the Ruskies build these things?’ said Gallen.
Aaron shrugged. ‘The Russians were using STARs in the Arctic Circle since the 1970s, mainly for remote communities and drilling operations. We had nuclear power in McMurdo, in Antarctica. But those old Russian STARs were uranium-powered; they were stable and were quite large units mounted on barges.’
‘Where did the plutonium come in?’ said Gallen.
‘More energy from a smaller unit,’ said Aaron. ‘The developers decided there was a large market for a nuclear power station you could carry on the back of a Dodge Ram. Florita had the perfect test bed for them — a sea-bed drilling rig, for Christ’s sake.’
‘So,’ said Hansen, ‘these terrorists don’t want to blow up the nuclear reactor? They will melt it down?’
‘I don’t know,’ said Aaron. ‘We’ve been keeping an eye on the Ariadne project but the hijacking surprised us.’
‘We should think about this,’ said the Swede, flashing a look at Gallen.
‘We should?’ said Gallen. ‘What should we think about?’
Looking through the bubble windscreen as he manoeuvred the sub with a grip in each hand, Hansen’s eyes grew wide. ‘It can’t be,’ he whispered, shaking his head softly.
‘Can’t be what?’ asked Aaron.
Hansen looked as if he’d eaten a bad oyster. ‘No one is so evil, surely?’
‘Try me,’ said Gallen.
Hansen took a calming breath. ‘These well heads are on a geological feature called the Gakkel Ridge. You know of this?’
‘No,’ said Gallen.
‘The Gakkel Ridge sits at the confluence of two tectonic plates,’ said Hansen. ‘Beneath the ridge are vast domes holding down trillions of litres of compressed CO2.’
‘Is that bad?’ said Gallen.
‘At these depths, it’s almost impossible for an undersea volcano to erupt and disperse its plasma.’
‘Yes?’
‘But the Gakkel Ridge is so volatile, and it develops such incredible gas pressures — maybe twenty times the pressures you see in the St Helens eruptions — that it can explode even under the weight of three kilometres of ocean.’
Gallen felt reflux. ‘So a nuclear reactor in meltdown — that would ruin this oil field for Oasis, right?’
‘Forget about an oil field,’ said Hansen, exasperated. ‘If you puncture one of these Gakkel domes in the wrong place, you could tear apart the entire sea floor.’
CHAPTER 65
‘Can we hit the lights?’ said Gallen as they saw the first signs of the Ariadne’s submersible beneath them.
The tiny cockpit was plunged into inky blackness as Hansen killed the lights, Gallen and Aaron gasping slightly at the shock of it. The totality of the light deprivation had a swallowing effect that instantly made human existence seem insignificant.
‘Shit,’ said Gallen, breathing out. ‘That’s fricking dark.’
‘Oh boy,’ said Aaron. ‘This isn’t my thing.’
‘You sure they can’t see us?’ said Gallen as Hansen eased off the throttles and let the Sea Otter sink to the rear of where the other sub’s lights were throwing.
‘They have good sonar, and they’ll be able to sense something behind them,’ said the Swede as the Sea Otter hovered fifty feet to the rear of the white sub. ‘But their actual vision is forward-facing.’
Gallen leaned towards the glass porthole as he let his eyes adjust to the environment. The white sub’s lights illuminated the muddy ground in front of it, and sediment rose in clouds as the props went on and off as it positioned itself. There was a large black 2 painted on the roof of the vessel.
‘What are they doing in the mud?’ said Gallen.
‘Could be the reactor,’ said Aaron. ‘It may have taken some time to find it on the sea bed.’
‘How much air do they have?’ said Gallen, watching the sub screw around like a pig with its snout in the mud.
Hansen made a clicking sound. ‘About three hours.’
‘That means they have about two hours left,’ said Gallen.
‘There,’ said Aaron, as the white sub’s pig-rooting ceased and it slowly rose out of the sediment cloud.
They breathed softly as they waited for the white sub to become clearer. Then, as they watched it ascend thirty feet off the muddy bottom, it slowly swivelled on its axis.
‘Shit,’ said Hansen, pushing one of the hand grips forward as the front glass plate of the white sub turned to ninety degrees. ‘She’s coming about.’
The Sea Otter lurched to the port side, just avoiding the blinding floodlights of the spinning white sub. As they dipped out of the way, they looked up and saw it: the pale blue reactor room, held between two mechanical arms in front of the white sub’s windscreen, and being carried like a garbage dumpster.
As they blended into blackness, the Sea Otter suddenly dropped.
‘No,’ said the Swede, as he struggled to control the vessel. ‘Turbulence.’
He soon had the vessel righted but he couldn’t stop it immediately, and the Sea Otter bounced on her side into the sea bottom.
Sitting in blackness and total silence for two seconds, they listened to one another’s nervous breathing.
‘The sub had a backwash,’ said Hansen. ‘Should have read that better.’
The silence was total and Gallen felt an important question formulating. Aaron beat him to it. ‘We lost power, Hansen?’
‘There’s a back-up,’ said Hansen. ‘But that doesn’t mean we don’t have damage.’
Gallen blinked and still couldn’t see a thing. The silence was broken only by the sound of Hansen’s fingers moving over a panel. Then he heard a click; and a soft whining hum started up and the instrument panel once again had the red backlight behind it.
‘Are we stuck?’ said Aaron, his voice slightly too panicky for Gallen’s liking. He’d heard that tone in Mindanao, where barracks bullies and cadre course heroes suddenly found they didn’t like being in a tropical jungle at night. Especially not when the Abu Sayyaf ambushers were about.