Press release from WSDOT:
http://www.wsdot.wa.gov/News/2010/08/31-PortofTacoma.htm
WSDOT is examining locations in the Port of Tacoma to build up to 44 of the pontoons needed for the new SR 520 bridge. One possibility may be Concrete Tech, who among many other projects built the beams for the Disney World Monorail.
This would be great news for the port and good for the project as finished pontoons could be delivered up Puget Sound to Seattle, then taken through Union Bay to Lake Washington. Plus, it was done here before for the new I-90 floating bridge.
Ben