DENVER — The city of Denver and Great Hall Partners, the developers of the renovation project at Denver International Airport, are entering a critical phase.

Both parties will soon meet in private negotiations to determine the severity of the concrete issue at the airport.

For the first time, Great Hall has publicly released a report citing how the project could be delayed until 2024 over a belief the current concrete at DIA lacks enough structural integrity to carry out the design plans for the airport’s renovation.

FOX31 previously reported how delays could cost more than $300 million.

But the city disagrees with that assessment.

Airport officials released a separate independent assessment of the concrete at DIA by a structural engineer.

That engineer, Ronald Hamburger, said he believes the airport’s concrete could sustain the development. However, he cautioned further testing should take place in the years to come.

DIA officials declined an interview request Wednesday but they sent this statement:

“The Airport is disappointed about the Developer’s delays on this important project. The Developer’s reported schedule does not appear to account for required mitigation such as proper staffing, appropriate design and work sequencing, and any other actions the Developer must take to address project delays. In fact, the Developer’s own report indicates its projected delay is subject to further mitigation efforts.  Given the Developer’s continued reports indicating delays, we are in confidential negotiations to work through these issues and expect to know more about schedule and budget implications, if any, later this summer. We are obligated to hold the Developer accountable under the P3 contract for Denver residents and passengers.”