Metro unveiled its preliminary plans for the bus tunnel in January 1984, selecting five sites for stations along 3rd Avenue and Pine Street: at Union Station, the King County Courthouse, between Seneca and Union streets, at the Westlake Mall, and near the Washington State Convention Center. The Burlington Northern Railroad opposed Metro's preference for the tunnel to cross the existing Great Northern Tunnel by going under it, the agency stating that passing over would require a cut-and-cover tunnel that would disrupt City Hall Park. The following month, Metro announced that it would use a fleet of 200 dual-mode buses for the first decade of tunnel operations, with an eventual switch to subway trains. The bored tunnel would be able to carry 180 buses an hour in each direction, serving either a wide island platform or two smaller side platforms that would be dug out from the surface. In April, Metro published the draft environmental impact statement for the tunnel project, estimating a cost of $387 million (equivalent to $ million in dollars) and a completion date of June 1989. The cost of the project drew criticism at public hearings for using a significant portion of Metro's capital budget, a total of $840 million from sales tax revenue approved by voters in 1980, as well as potential disruption to business during the cut-and-cover construction of the stations and Pine Street segment of the tunnel.