CCM's 'Long 80' proposal was selected as the preferred project. The Evaluation Panel concluded that this proposal best met the evaluation criteria and represented the best value for money. However the 'Long 80' differed significantly from the tunnel put to tender. As a result, a Supplementary EIS (or SEIS) and a modified Planning Minister's approval were considered necessary. These caused major changes to the project's scope and costs. In particular:
■ the Department of Health required more stringent in-tunnel carbon monoxide standards
■ representations and further modelling resulted in significant changes to the Domain connection between the CCT and the Eastern Distributor, Cowper Wharf Roadway connections and East Sydney traffic arrangements, as well as adjustments at the William Street ramp
■ tunnel facilities required changes, particularly the signage
■ infrastructure owners additional requirements (such as moving a power sub-station) became apparent
■ additional community urban design treatments were required.