Warren,
all of the volcanoes in the so called Pacific Ring of Fire are active. My. Rainer, Mt Hood, of course My. St Helens, and Mt. Shasta and Mt. Lassen. At times you can see the team from Lassen forming a cloud around the top of the cone and if you drive up there, they have plenty of active areas where you can see steam boiling mud pots and such. One place called the sulphur works is as yellow as if you had painted it and stinks until I limit my time there. Lassen has a continual record of seismic activity. But they seem to think that Rainer will be the next one to blow.
Ron