An investigation into massive cost overruns at a new veterans hospital outside Denver found VA officials didn't understand the complicated contract process they adopted and says they mismanaged change orders.

The half-finished hospital in suburban Aurora is expected to cost up to $1.73 billion, nearly triple the earlier estimates. An Army Corps of Engineers report released Thursday blames the VA's management of the project.

The report also cites repeated changes in the size and scope of the project for the cost overruns and delays.

VA Deputy Secretary Sloan Gibson said his department accepts the findings and is making changes.

The Corps of Engineers warned that the VA needs to make fundamental changes in the way it handles construction projects or it will incur delays and overruns on future projects.