Technical Real Estate will seek up to tens of millions of dollars in compensation for relocating the $1billion data centre, taking into account money spent on assessments and additional infrastructure the new site might require.

Technical Real Estate director Andrew Campbell told The Canberra Times yesterday, ''Putting in new power lines, telecommunications lines and gas lines is expensive, so the compensation will be very dependent on where we end up.''

The firm has asked the Government to find a site by Christmas because it has already invested so much time and money.

''I'm hoping for an early Christmas present a data centre approval wrapped up in a nice little bow,'' Mr Campbell said.

The company had not decided whether to take the project out of Canberra if the Government did not find a site before then.

Greens MLA Amanda Bresnan said she did not understand why the company had asked for a new site to be chosen by Christmas.

''The original timeframe for the completion of the [environmental impact study] was April 2009, so I'm unsure why all of a sudden we've got this December timeframe,'' she said.

Ms Bresnan said her party was still opposed to the data centre proceeding at the Tuggeranong site despite the environmental impact study and a separate health impact study, issued on Monday, finding no significant concerns with the project.