The CEOs of nine major airlines have asked Denver officials to delay by four months a final decision to upgrade the airport terminal. Design and construction costs for the project are estimated at $650 million to $775 million. A city council review of the contract with concessionaire Ferrovial is scheduled for later this month. The project consolidates and relocates security-screening areas, adds more food options and accommodates increased passenger traffic. In a letter sent to the city in late June, the airline CEOs said they object to paying higher rates for a project that carries “significant concerns on both the financial and operational fronts.” Airport CEO Kim Day in a statement noted, “The goal of this project is to address our current vulnerabilities created by the exposed TSA checkpoints and, at the same time, greatly expand the capacity and life of the terminal.” She said “improved concessions” are not the impetus for the project.