what was the scandal about?
It was over the discovery that granite to be used by Metro in the tunnel's stations had been sourced from South Africa.
Downtown Seattle Transit Tunnel
A minor scandal involving the bus tunnel project emerged in late 1988, over the discovery that granite to be used by Metro in the tunnel's stations had been sourced from South Africa. 
where is downtown seattle transit tunnel? Seattle, Washington, United States who built it? UNANSWERABLE which are the different stations that the tunnel connects to? Westlake and International District/Chinatown stations does it also connect to any route? Yes, it connect bus routes. how does the transit run? The OCC controls vehicle movements by using on-board radio-frequency identification tags installed on tunnel buses and light rail vehicles, their locations tracked by passing over induction loops embedded in the tunnel roadway. were there any proposals made to make a subway ealier? Yes, there were several proposals for a cut-and-cover subway tunnel. were any of them approved? Yes, a proposal as part of the Forward Thrust initiatives was approved. can you tell me something more about the thrust? They were a series of bond propositions put to the voters of King County. when was the proposal approved by them? 1968 was any proposal put forth for constructing a bus tunnel? Yes, a downtown bus tunnel. and was the proposal approved? Yes, the concept of a downtown bus tunnel was first proposed in 1974. when was the construction of the tunnel complete? UNANSWERABLE how much did it cost to build the tunnel? $25.9 million was there any scandal associated with it? Yes, a minor scandal emerged in late 1988. where did it happen? UNANSWERABLE
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Downtown Seattle Transit Tunnel [SEP] South African granite scandal
A minor scandal involving the bus tunnel project emerged in late 1988, over the discovery that granite to be used by Metro in the tunnel's stations had been sourced from South Africa. The Verde Fontaine granite was quarried in South Africa, which had been under Apartheid rule at the time, but was cut and finished in Italy, allowing for it to be approved despite the Metro Council's ongoing boycott of South African goods. The Verde Fontaine granite was selected for use as benches and interior walls in Westlake and Pioneer Square stations by architecture firm TRA; Metro was unaware that Verde Fontaine was only quarried in South Africa.