Yikes! That doesn’t sound good at all. What happens if they have an earthquake?
Someday it's gonna happen and it'll be a doozy. Cascadia subduction zone. Would not want to be anywhere near there when that happens.
Better question is what happens when Mt Rainer erupts ... lahar (mud) flows will wipe out Tacoma and parts of Seattle not to mention 14,440 feet of mountain falling on them
Earthquake? Seattle area over due for 9.0 quake. See images from the 1964 AK earthquake to get idea, but multiplied many times.