A new report says the ongoing renovation project at Denver International Airport could be delayed up to 10 months after tests show weaker-than-expected concrete in the main floor of the airport’s terminal.

The Denver Post reports that airport spokeswoman Stacey Stegman says the extent of the delay – and the severity of the problems – won’t be known until at least April.

That’s when more testing of the concrete is expected to be complete.

A preliminary estimate by Great Hall Partners, the private consortium carrying out the $650 million renovation project, is that the concrete issues could delay the project by 209 work days.

That would equate to about 300 days when weekends and holidays are added in – or about 10 months beyond late 2021, the original target for completion.

DIA is relocating its security checkpoints from the floor of its main terminal to the same floor as the passenger check-in stations. The move will open up extra retail space in the terminal.