I read the article: [seattletimes.nwsource.com]

However I could find no mention of whether Sound Transit was using resilient wheels. If they are going with solid wheels like BART there will be more noise. BART is very noisy and it gets worse with corrugation. The only way I imagine to really tackle wheel squeal is to devise a way for the inside wheel on a curve to spin less than the outside wheel. At one time the Germans were trying magnetic powders to achieve this end. I think ameliorating wheel squeal is one of the objectives of radial trucks but I don't know how successful that approach has been.

Low noise was one of the touting points of the French rubber-tired subway technology but it has other technical limitations. Noise and visual blight of proposed hsr elevateds is currently a bitter controversy on the SF Peninsula.