CHANNEL TUNNEL Rail Link engineers were this week locked in battle with residents living near the line's St Pancras terminus over the right to work 24 hours a day on the project.
Client Union Railways North (URN) has argued that overnight working will be needed to allow construction of a 400m long underground box for the new Thameslink station to be completed in its 25 week blockade.
Work on the box is due to start in September.
But Camden Council planning officials have refused permission, forcing URN to take the issue to a public inquiry.
Giving evidence at the inquiry this week, URN claimed that works will not disrupt local residents unacceptably, and has offered a raft of appeasement measures to those worst affected such as blackout curtains, ventilation, secondary glazing and in extreme cases a grant for hotel accommodation.
Original plans to build the box had assumed a cut and cover construction sequence. But work would not be allowed past 10pm due to the noise and dust caused by this type of works.
The team has now proposed a top down method, with a precast beam and insitu slab roof placed on contiguous piled walls already in place. Excavators will hollow out this box with all noise and dust contained.
But this method is slower, and if the new working hours are not approved the programme will exceed the 25 week blockade and delay the project by up to 10 weeks. This would cost URN up to £50M in lost revenue from development, line charges and interest, plus £10M in compensation to train operators.
The inquiry was ongoing as NCE went to press.