Ineos Chlor has completed the first stage in the construction of a combined heat and power station fuelled by waste from Manchester, Merseyside, Halton, Cheshire and Warrington.
The energy giant will now hand the site over to O'Hare Engineering to continue the work.
The Government granted permission to allow the plant to go ahead with a capacity of 100 megawatts in Runcorn last September.
Ineos said the first phase involved basic ground work and that old pipes, cable and railway track was removed.
The second phase is set to finish next summer and then the incinerator will be built by Keppel Seghers.