Local news service RTBF reported that 227 builders were found last week working illegally on the Baudour site.
That followed a similar raid in November when inspectors found another 115 workers without the correct documents.
People without the required documentation came from the UK, Romania, Bulgaria and Hungary
Google told RTBF: “We asked ISG, our main construction contractor, responsible for all the workers on the site, to cooperate fully with the social inspection services and to resolve any problem as quickly as possible.
“We have set up a clear code of conduct for all our suppliers, which are contractually bound to comply with all local laws and regulations in force. It is important for us that this case is settled.”
ISG declined to comment.