Anything really close to the Portland Metro area WILL be subject to testing by DEQ. Anything far enough outside Portland to avoid DEQ can turn into an unpleasant commute. And your car may pass with aftermarket forced induction anyway. Plenty of stock and modded WRXs pass, if that helps your peace of mind. If you have a main cat and no CELs, you're probably OK. But I know of NO turbo contiques in Portland.
At which hospital is she likely to be?
Mt. Hood Medical Center is pretty far in the eastern suburbs, while St. Vincent Hosp. is on the close edge of the western suburbs. Don't plan to live by one and have her drive to the other. Tuality is in Hillsboro and you could commute from a farm close to the coast range. If she goes to Meridian Park Hosp or Willamette Falls or Kaiser Sunnyside, that's far enough south or southeast that you can live past the S/SE suburbs to avoid DEQ that way. Meanwhile, if she's gonna be at Emanuel Hosp. or Providence Portland MC or Woodland Park, you may even look into living in Vancouver WA, I do NOT know if Washington State/Clark County does emissions testing like the Portland metro area does. OHSU and Good Samaritan are close to downtown street traffic. But realistically, anywhere you end up around here you'll be close to the coast, the gorge, the cascade range, windsurfing, downhill skiing, flyfishing, backpacking, mountain biking, etc. And yes, we get some non-stop light rain.
