Dear Daniel, Was there only a month ago and I saw no big rigs parked anywhere near the Silver Dollar Casino. Parking was for cars only, and very limited. If you can find parking for your big rig, they are worth getting on the Seattle Light Rail as they have great food and large portions, at a reasonable price!
Sorry the parking lot cannot accommodate a large vehicle, but there parking at Silver Dollar Renton which is not too far from SeaTac.
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