eruption. spirit lake had so much sediment dumped into it by the mount st. helen's eruption that the surface level of spirit lake rose by 210 feet. and that's up above castle rock and so that nightmare, that potential nightmare, is looming over the town of castle rock. and it still is. they eventually built a tunnel to channel outflow from that lake so it would not loom so dangerously for the town. now 35 years later they are worried now they might have to รง go in and widen that tunnel because it's filling up today with that sediment again and threatening the town again. mount st. helen's blew up 35 years ago today. it killed 57 people and it changed the shape of the earth. it moved rivers, turned a mountain into a crater. 35 years later it is still posing challenges. the "seattle times" today does