Each arcology was constructed in a similar fashion on newly-compliant Imperial worlds: first would come the labourers and their families, relocated by the tens of thousands from towns and villages all over the hemisphere. They would be resettled in a town at the site of the new arcology, which would spread outward in all directions as its population swelled. Then, once there was a large enough labour pool that had been sufficiently trained to begin work, the digging of the arcology's foundation would begin. The structure would grow in stages, expanding outwards, upwards and downwards at the same time. Little by little, the arcology would swallow up the town, its residents progressively reassigned to districts inside the structure itself. The population would continue to grow as well, along with the civil services and bureaucracy that went along with it. In theory, the population and organisational growth would match the growth of the structure so closely that by the time the structure was complete, the arcology would be fully populated and self-sufficient. Of course, such things rarely ever went precisely according to plan.

'How many people are at Northwilds these days?' Zahariel asked.

'You mean civilians? About five million, all told,' Morten replied. 'About a quarter of that are Imperial citizens from offworld: Administratum officials, engineers, industrial planners and the like.'

Zahariel consulted facts and figures committed to memory before leaving Aldurukh. 'A stage one arcology is built to support twice that number,' he observed. 'So half of the structure is still unoccupied?'

Morten shrugged. 'The Imperium's industrialisation plan calls for twenty stage-one arcologies across Caliban, but the planet's population won't be able to support that for some time yet.'

The Librarian frowned thoughtfully. 'That seems like a great deal of extra work. One would think that they would build new structures as needed, rather than all at once?'

Morten spread his gnarled hands. 'Who can say? The Administratum has its reasons, I don't doubt.'

'How is the population distributed throughout the arcology?' Zahariel inquired.

'We're keeping the natives penned into the lower levels,' the general rasped. 'The garrison, the Administratum infrastructure and the offworld residents are housed on the upper levels, where we can keep them secure.'

Zahariel gave the general a flat stare. 'Natives?' he said.

Morten's scowl vanished. 'My apologies, sir,' he said, straightening in his seat. An embarrassed flush began to spread up his thick neck. 'Just a figure of speech. I meant no offence.'

'No, of course not,' the Librarian replied coolly. 'How are you managing to provide basic services to the population?'

Morten drew in a quick breath. Well, I won't deny it's difficult. The lower levels bore the brunt of the riots, so a lot of the infrastructure was damaged. We're sending in work teams every day with armed escorts to perform repairs, and we've set up medicae facilities at strategic points to care for the injured.'

'So how much of the lower levels are without light or running water at this point?' Zahariel asked.

'Only about twenty per cent,' Morten said. 'If we can keep any more full-scale riots from breaking out, we can knock that number down even further in the next couple of weeks.'

Zahariel nodded, keeping his face impassive. Twenty per cent without power or water meant roughly a million people trapped in the dark, shivering in the cold and living off military ration packs for the better part of a month. 'Is there no way to relocate the affected residents to another level?'

Morten's craggy brows went up. 'Sir, you must be aware that an unknown number of the natives - excuse me, citizens - are also likely members of the rebellion. It's much more sensible from a military standpoint to keep them isolated and restore service to them than turn them loose in another part of the arcology where they can cause more mischief.

Zahariel turned back to the window and breathed deeply, biting back the outrage he felt. 'Is this sort of tactic normal when dealing with civil unrest?' he asked.

'Of course,' Morten replied. 'You've got to get it through their heads that when they destroy Imperial property they're only going to make their lives harder and more miserable. Sooner or later the lesson sinks in.'

And how many rebels do you create in the process, Zahariel thought?

The shuttle had descended to about two thousand metres by this point, and its turn sharpened as it came in for its final approach. Zahariel saw plumes of smoke rising from the arcology's flanks near ground level, suggesting that the populace was far from learning General Morten's brutal lesson. He was shocked to feel a perverse sense of pride at the thought.

They continued their descent, passing below fifteen hundred metres before the shuttle pilot pulled up the nose of his craft and flared his thrusters for a vertical landing. The transport touched down on a broad landing pad, one of dozens that jutted from the arcology's northern face, with scarcely a jolt. Morten grunted in satisfaction as he unbuckled his safety harness and climbed wearily to his feet.

'My inspection will likely take the better part of three hours,' he said to Zahariel. 'Do I need to stretch it out further?'

'No need,' Zahariel replied. He had yet to climb from his seat. 'If I'm not back by the time you are done, return to Aldurukh without me. I will arrange for my own transport.'

Morten paused, as though he wanted to inquire further, but after a moment he mastered his curiosity and gave the Librarian a curt nod. 'I'll bid you good luck then,' he said, then turned on his heel and headed for the exit ramp.

Zahariel listened to the clang of the general's boots as he descended the ramp. One of the shuttle pilots passed through the passenger compartment, headed aft to check on the shuttle's engines. He waited a full minute more, then rose to his feet and pulled off his plain, white surplice to reveal a black body glove beneath. The rebel leaders had agreed to the meeting only on the condition that he come unarmed and unarmoured. The stipulation surprised and irritated him; did they imagine he would call for a parley with treachery in mind? He'd swallowed his aggravation and agreed nonetheless. There was too much at stake to haggle over such trivial details.

The Librarian reached into an overhead locker and drew out a neatly-folded bundle of cloth. Zahariel unfurled the heavy cloak with a snap of his wrists and drew it about his shoulders. When he closed the clasp, the cloak's cameleoline outer layer activated, matching the grey hues of the compartment in less than a second. He drew the cloak's deep hood over his head and headed quickly to the ramp.

Outside the shuttle the air was cold and brisk, with a strong wind blowing down from the mountains. Tattered streamers of smoke curled around the lip of the landing pad; he grimaced as he caught the mingled smell of ash and melted plas. Across the pad, a deep alcove led to a pair of blast doors that gave access to the arcology itself. A shuttle technician stood near the alcove, his back to Zahariel as he tried to wrestle a heavy refuelling hose from a recessed bay set into the pad itself.

The Astartes moved swiftly across the pad, the faint sound of his footfalls lost in the idling whine of the shuttle's engines. He passed the technician close enough to touch him if he'd wished; the man glanced up irritably as he felt the wind of Zahariel's passage on his neck, but his gaze swept right past the Librarian without registering his presence.

Clutching the cloak about his broad frame, Zahariel entered the broad, shadowed alcove and paused beside the blast doors. As near as he could reckon, he had six hours before the rendezvous on sub-level four.