These are not hot springs but fumaroles. Way too hot and some very corrosive, so definitely no soaking. Also, Bumpass hell has a designated walkway you must stay on.
You wouldn't want too. Burning, boiling water mud and steam with a nasty sulfur smell.
Noooooooooo! At least at Bumpass Hell these are not the soaking kind of hot springs, but the "you're gunna die" kind. There are hot springs outside of the park that are ok for soaking, but none inside Lassen.
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