Sen agreed the cold side was the route. She would not send engineers into it.
“Send the pipe crews,” she said.
They were at the service passage’s mouth: a narrow door in the lowest chamber’s back wall, behind the cold stair, where the rock gave way to the lattice’s outer skin and a gap ran between them, a crawlway of old steel walls and grit floor, lit by nothing. Sen had opened it with one of the keys on her ring. Cold air came out of it, and a smell of rust and stone.
“Engineers want to measure things,” Sen said. “Then they want to fix them. They’ll get in there with a torque bar and a drawing and try to turn a fastener the drawing says should turn.” She looked into the passage. “And the fastener won’t turn, because it’s been bonded to the wall since before your grandmother was born, and the engineer will put more force on the bar, and the wall will crack.” She shook her head. “Send the pipe crews. They know how to free a corroded joint without cracking the metal around it. They do it every week.”
“Who?”
Sen was slow to answer. She was looking at the passage’s mouth, at the grit on its floor, and Mara saw her lips move. Counting something. The fasteners she could not see, perhaps. Or the crews she had.
