There was nothing exciting beyond the doors, just another set of the same doors a few metres further on. But at least the lights were on. Those doors, too, bore the same faded radiation sign.
Uneasy glances at their RainbowRads still reassured them before they continued through into yet another section of corridor, again only a few metres long.
Everyone now stopped dead as, one after the other, the three RainbowRads turned from white to yellow. The probable cause being the large circular steel door that filled the wall at the far end.
Bodil and Gregor looked at Ellie. Ellie took a step forward but that was as far as she got because Gregor's fingers curled over her shoulder and stopped her dead.
"Stay here, Miss. I'll see if it's safe."
Gregor tugged on his pendant, snapping the chain effortlessly. Holding it out in front of him like a talisman, Gregor moved slowly down the corridor.
He was almost at the great steel door before the glowing yellow bauble turned to orange. He stopped.
"Greggie. Don't go any further."
Gregor half turned and looked over his shoulder.
"I wasn't going to." He pointed to his left. "Maybe we don't have to. There is another doorway. I can see lights on a panel.
" Gregor, still holding out the pendant, very slowly made his way over to the left-hand wall and disappeared through the open doorway.
Bodil and Ellie strained to hear what Gregor was doing. Half a minute passed before the giant's head poked around the doorway.
"It's okay Miss. My pendant has stayed orange. This is a control room. There's also this window where you can see through to what's behind the big door."
Ellie and Bodil set off together. The opportunity to see what lay beyond that imposing door was stronger than the RainbowRad's insipid warning to find a new route.
Despite Bodil having seen a pre-Fall reactor before, what was visible through the metre-thick lead glass window took more than a moment to make sense of.
The much smaller reactor at the LifeNet facility in Iceland was mainly a large empty room with a couple of overhead cranes, lots of pipes and gauges and a bare floor area.
The whole floor had been open and clear with an arrangement of 'tiles' in the centre that were flush with the floor itself and together formed a shape like a fat cross.
The same thing was going on here except that the pipes were broken, the gauges all read zero and the fat cross in the middle of the floor was anything but open and clear.
"Mother's Bra Straps." Was Bodil's first reaction.
Ellie was at her shoulder.
"I'm no expert, and I've never had the opportunity to see one of these things, but that doesn't look right Professor Hill."
Bodil gathered her thoughts before starting to speak. When she did, she was in full professor mode.
"Okay. Normally in a reactor of this type, the water of the primary coolant system which surrounds the fuel cells is heated by the controlled reaction in the nuclear material.
The control over the reaction is maintained by raising or lowering neutron-absorbing rods between the fuel cells.
This super-heated water then goes through a heat exchanger and heats up the water of the secondary coolant system which drives the steam turbines which generates the electricity."
Ellie was nodding, still staring at the obvious re-engineering that had been done on the other side of the glass.
"I guess that isn't what is going on here then."
"Absolutely not." Bodil swallowed. "From what I can make out," she pressed her finger against the glass.
"The control rods have been removed and are laying in a pile at the back of the room over there.
The, erm, the fuel cells have been withdrawn from the reactor pressure vessel and encased in whatever those things are.
I've never seen anything like them, but I'm guessing they are generating the electricity."
"And you'd be right, Professor."
Bodil looked at Ellie.
"How do you know that?"
Ellie didn't answer straight away but moved to the central desk with the lit indicator lights and active meters. Her eyes flicked over the display as she spoke.
"Those 'things', Professor, are called Free Electron Strippers. What they are doing is farming the free electrons being thrown off by the collision of slow neutrons in the fissionable material."
Ellie paused, missing Bodil's expression and Bodil watched Ellie use her finger to do some quick calculations in the seventy years of accumulated dust on the desk.
When she finished, Ellie let out a relieved 'hmph'. Then she turned to where the professor and Gregor were watching her.
"Fortunately, they also contain material that confines the radiation to within the strippers. Otherwise, we'd all be dead standing here."
Bodil's surprise at Ellie's display of knowledge turned to a grin.
"I didn't know we had things like that now, never mind seventy years ago. Perhaps I should pay more attention to what the science department is up to."
"Not your fault Professor," Ellie replied, unsmiling. "The company that now makes modern FESs didn't even begin development of the idea until fifty years ago.
Those FESs we can see through there are primitive by comparison and nowhere near as safe.
The readings show that the FESs are becoming hot and my calculations conclude that at some point the neutron reflecting material will break down, and when that happens,
there will be a meltdown of the fuel cells." There was a drawn-out silence before Ellie moved for the door. "We should get back."
They picked up Hobbes and Weis on the way and returned to the big distribution board.
Ellie and Bodil explained what they had found, and the fact that the tech 'they' had installed was doomed to fail at some point in the near future.
"Can't we just turn the bloody thing off?"
Ellie shook her head.
"It wouldn't make any difference. Without the old control rods in place, the reaction would still continue.
In fact, disrupting the power from here would only speed the decay of the FESs up because the reduced current flow coming out of the FESs add to the internal heat build-up."
They discussed what they could do, which wasn't much. What they should do, which was to inform the whole greater London basin inhabitants of the danger.
And what they would do, which was to make their way back the way they had come and get back to Wembley.
"There's nothing more we can do here," Ellie said. "We've learned that whoever was here seventy years ago needed power for, something. Maybe two somethings.
" She bobbed her head towards the distribution panel. "We even have our clues as to where to look next. 'F' and 'W Cst'"
They strapped on their packs and were just about to leave the generator chamber via the corridor they had come in by when Gregor halted them with a hand gesture while his other hand held up
a finger to his lips for silence. Then four pairs of eyes followed that same finger as it slowly moved to point up and to the left.
To where, in the other corner from the steps to the reactor room, four figures shielded their eyes from the light as they crouched and swayed at the top of another flight of steps.
Gregor slowly sank to his knees behind the leftmost wing of the distribution board. The others followed suit.
"Shit." Weis hissed, checking his weapon. "Fucking stalkers."
Bodil thought back to the lecture from Sergeant Glasser. Straining her memory, she tried to recall 'Stalkers' but failed.
Gregor put his hand on the little ranger's shoulder.
"What are Fucking Stalkers?" he whispered.
"Not supposed to be fucking here," Weis replied. He carefully turned to poke his head around the side of the distribution board.
"They're moving down, being bloody cautious, not used to the light I guess." There was no sign of his habitual 'Pardon my language'.
When he moved back to sit with his back against the board, Weis looked scared.
Gregor put his hand on Weis' knee this time, firmly.
"What are they?"
"Ow, leave off. What are they? Nasty bastards, that's what they are. They've been showing up from up north. Never seen four at once, though. Usually just one of 'em.
They creep up on whatever it is they're hunting and then..." Weis made a sudden grabbing gesture. "Don't stand a chance."