Chronology of uranium tailings dam failures
(last updated 19 Nov 2012)(tailings releases without embankment failure not listed)
| Date | Location | Parent company | Type of Incident | Release | Impacts |
|---|---|---|---|---|---|
| 2012, Nov. 4 | Sotkamo, Kainuu province, Finland (nickel mine, with uranium by-product production planned) | Talvivaara Mining Company Plc  | leak from gypsum pond through a "funnel-shaped hole" | hundreds of thousands of cubic metres of contaminated waste water | nickel and zinc concentrations in nearby Snow River exceeded the values that are harmful to organisms tenfold or even a hundredfold, uranium concentrations more than tenfold (view details) |
| (1994) | Zirovski vrh, Slovenia | Rudnik Zirovski vrh, Gorenja vas | ongoing slippage of the slope (7 million t) with the "Borst" tailings deposit (600,000 t) on the top, at velocity of 0.3 m per year | - | - |
| 1994, Feb. 14 | Olympic Dam, Roxby Downs, South Australia | WMC Ltd. | leakage of tailings dam during 2 years or more | release of up to 5 million m3 of contaminated water into subsoil | ? |
| 1985 | Lengenfeld, Vogtland, Germany | Wismut | localized dam failure | ? | minor |
| 1984, Jan. 5 | Key Lake, Saskatchewan, Canada | Cameco (67%), Uranerz (33%) | overtopping of process water reservoir, due to poor management | 87,330 m3 of contaminated water | ? |
| 1979, Jul. 16 | Church Rock, New Mexico, USA | United Nuclear | dam wall breach, due to differential foundation settlement and direct exposure of the dam to tailings solution | 370,000 m3 of radioactive water, 1,000 tonnes of contaminated sediment | Contamination of Rio Puerco sediments up to 110 km downstream > Download: Abnormal occurence; Mill Tailings Impoundment Failure, U.S. NRC, Federal Register Vol. 45, No. 8, January 11, 1980, p. 2424-2425 (1.4M PDF - ADMAS Acc. No. ML101040064)
|
| 1979, Mar. 1 | Union Carbide, Uravan, Colorado, USA | Union Carbide | two slope slides, due to snow smelt and internal seepage | - | - |
| 1977, Apr. | Western Nuclear, Jeffrey City, Wyoming, USA | Western Nuclear | Tailings slurry overtopped the embankment because of insufficient freeboard space, considerably less slope than the requisite 3 horizontal to 1 vertical, and a loss in structural integrity caused by the melting of snow interpersed with the fill used to construct the embankment. | 40 m3 of tailings and 8,700 m3 of liquid | "no offsite contamination" |
| 1977, Feb. 1 | Homestake, Milan, New Mexico, USA | Homestake Mining Company | dam failure, due to rupture of plugged (frozen) slurry pipeline | 30,000 m3 of tailings and 7,600 - 30,000 m3 of liquid | no impacts outside the mine site |
| 1976, Apr. 1 | Kerr-McGee, Churchrock, New Mexico, USA | Kerr-McGee | dam failure, due to differential settlement of foundation soils | "minor quantity" | ? |
| 1971, Mar. 23 | Western Nuclear, Jeffrey City, Wyoming, USA | Western Nuclear | dam failure, due to break in tailings discharge line | ? | "no offsite contamination occured" |
| 1971, Feb. 16, | Petrotomics, Shirley Basin, Wyoming, USA | Petrotomics | secondary tailing dike failure | 7.6 m3 of liquid | liquid lost to unrestricted area |
| 1967, Jul. 2 | Climax, Grand Junction, Colorado, USA | ? | tailing dike failure of unapproved retention system | 1,200 - 12,000 m3 of waste liquid | effluent release into Colorado river |
| 1967, Feb. 6 | Atlas Corp., Moab, Utah, USA | auxiliary decant failure, overflow from main tailings pond overflowed aux. decant system | 1700 m3 | ||
| 1963, Jun. 16 | Utah Construction, Riverton, Wyoming, USA | ? | The dam was intentionally breached and a 2-ft depth of effluent was released to prevent uncontrolled release of the impoundment contents during heavy rain | ? | ? |
| 1962, Jun. 11 | Mines Development, Edgemont, South Dakota, USA | ? | dam failure, due to unreported causes | 100 m3 | tailings released reached a creek and some were carried 25 miles to a reservoir downstream |
| 1961, Dec. 6 | Union Carbide, Maybell, Colorado, USA | Union Carbide | dam failure from unreported causes | 280 m3 | effluent released did not reach any stream |
| 1960 | Gunnar mine, Beaverlodge area, Saskatchewan, Canada | Gunnar Mines Ltd. | dam failure | ? | tailings release into Lake Athabasca, creating Langley Bay tailings delta |
| 1959, Aug. 19 | Union Carbide, Green River, Utah, USA | Union Carbide | dam failure during flash flood | 8,400 m3 | tailings and effluent reach a creek and river |
| 1958, Apr. | Mayluu-Suu tailing #7, Kyrgyzstan | dam failure after earthquake and heavy rain | 600,000 m3 | a lot of houses in the town destroyed, people were killed, and the tailings were spread over 40 km down by the river, contaminating flood plains > View photo (UNEP/GRID-Arendal)
| |
| 1954 | Lengenfeld, Vogtland, Germany | Wismut | dam failure during flooding event | 50,000 m3 | tailings spread 4 km down by the river, create wetland by damming up |
- United Nations Environment Programme - Industry and Environment: Environmental and Safety Incidents concerning Tailings Dams at Mines, Results of a Survey for the years 1980-1996, May 1996, 129 p.
- United States Committee on Large Dams: Tailings Dam Incidents, Denver, CO, November 1994, 82 p., ISBN 1-884575-03-X
- U.S. Nuclear Regulatory Commission: Regulatory Guide 3.11.1, Rev. 1, Operational Inspection and Surveillance of Embankment Retention Systems for Uranium Mill Tailings, October 1980
- http://www.wise-uranium.org/mdafu.html
