Mine tailings dam failure and floodplain impacts on Soda Butte Creek, Montana and Yellowstone National Park

Related publication:

Marcus, W.A., Meyer, G.A., Nimmo, D.R., 2001, Geomorphic control of persistent mine impacts in a Yellowstone Park stream and implications for the recovery of fluvial systems: Geology, v. 29, no. 4, p. 355-358. (PDF file of article)

	Fig. 1.  Acidic, metals-contaminated overbank sediment on the Soda Butte Creek floodplain in Yellowstone NP, deposited by a dam-break flood when the McLaren mine tailings impoundment 24 km upstream (above Cooke City)  failed in 1950.  The tailings sediment here overlies overbank gravels deposited during an earlier large flood, probably in 1918.
	Fig. 2.  Discharge reconstructions with range of estimated uncertainty.  The dam-break flood produced high to extreme peak discharges (compare to 100-yr flood estimate).
	Fig. 3.  Hydrographs reconstructed at lower 4 locations, with distance below the McLaren mine tailings impoundment shown.  Even with downstream attenuation, the flood duration was almost certainly < 1 hr at all locations.
	Fig. 4.  Stream power graphs for the same 4 locations as above.  Despite extreme discharges, little floodplain erosion occurred because of low total energy expended and moderately high stream power.  A large mass of tailings was deposited as overbank sediment, however, resulting in persistent floodplain contamination.