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Field Trip Program

Hydrothermal Features

Aqua pools and yellow ground at Bumpass Hell hydrothermal area
Bumpass Hell hydrothermal area
NPS Photo

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Program can be scheduled at Sulphur Works, a roadside hydrothermal area one mile north of the Kohm Yah-mah-nee Visitor Center, or Bumpass Hell parking area, approximately 8 miles north of the Kohm Yah-mah nee Visitor Center.

Length: 30 to 60 minutes
Group Size: up to 35
Contact us on or after Feburary 1 for programs in May to July
Contact us on or after June 1 for programs in August and September


Steve Zachary

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Earth Science, Geology, Physical Science, Tectonics, Volcanoes
National/State Standards:
California State Standards
Field Trip Program