https://www.usgs.gov/centers/wyoming-montana-water-science-center/science/yellowstone-river-basin-water-quality
Yellowstone River Basin Water-Quality Assessment | U.S. Geological Survey
The Yellowstone River Basin (YELL) study-unit in Wyoming, Montana and North Dakota, is part of the U.S. Geological Survey's National Water-Quality Assessment...
yellowstone river basinwater qualityassessmentgeologicalsurvey