Subject
- Environmental protection1
- Groundwater flow1
- Hydrology -- Washington (State) -- Saint Helens, Mount, Region1
- Land use -- Oregon -- Planning -- Congresses1
- Regional planning -- Law and legislation -- Northwest, Pacific -- Congresses1
- Saint Helens, Mount (Wash.) -- Eruption, 19801
- Salmon1
- Soil moisture1
- Temperature -- Physiological effect1
- Water -- Pollution -- Washington (State) -- Saint Helens, Mount, Region1
- Water resources development -- Oregon -- Congresses1