Site investigation specialist Structural Soils starts work on the project this month with the job expected to run to the end of the year. Up to 100 workers will be deployed on site during busy periods.

The project requires the drilling of around 400 boreholes and trial pits across the site.

The material removed will give Horizon a detailed understanding of the ground conditions which will inform more detailed planning of the preferred site layout.

Charlie Tasker, site development director at Horizon, said: “The ground investigation work is another example of the rapid progress we’re making.

“This part of the project will take us most of this year to complete and will give us a huge amount of technical detail about the ground we want to build on.”

Alison Randall, Safety, Health, Environment and Quality Manager at Structural Soils, said: “We’re really pleased to be working on the Wylfa Newydd project again and we’re particularly looking forward to renewing the positive relationships we established with local suppliers last time we worked at the site.”