Chronology of major tailings dam failures – updated with Mount Polley

Just updated to include Mount Polley from
(from 1960 – last updated 6 Aug 2014)

Date Location Parent company Ore type Type of Incident Release Impacts
2014, Aug. 4 Mount Polley mine, near Likely, British Columbia, Canada Imperial Metals Corp. external link copper, gold tailings dam failure 4.5 million m3 of tailings and 10 million m3 of water tailings flowing into adjacent Polley Lake and, through Hazeltine Creek, into Quesnel Lake (Mitchell Bay)
2014, Feb. 2 Dan River Steam Station, Eden, North Carolina, USA Duke Energy external link coal ash collapse of an old drainage pipe under a 27-acre ash waste pond about 82,000 short tons [74,400 t] of toxic coal ash and 27 million gallons [100,000 m3] of contaminated water ash flowing through drainage pipe into Dan River
2013, Nov. 15-19 Zangezur Copper Molybdenum Combine external link, Kajaran, Syunik province, Armenia Cronimet Mining AG external link copper, molybdenum damage of tailings pipeline ? tailings flowing into Norashenik River for several days
2012, Dec. 17 former Gullbridge mine site, Newfoundland, Canada copper embankment dam failure, width 50 m non-consumption water advisory has been issued for the Town of South Brook (view details external link – Newfoundland and Labrador Department of Environment and Conservation)
2012, Nov. 4 Sotkamo, Kainuu province, Finland Talvivaara Mining Company Plc external link nickel, (uranium by-product planned) 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)
2011, Jul. 21 Mianyang City, Songpan County, Sichuan Province, China Xichuan Minjiang Electrolytic Manganese Plant manganese tailings dam damaged from landslides caused from heavy rains ? tailings damaged residential roads and houses, forcing 272 people to leave; tailings were washed into the Fujiang River, leaving 200,000 people without drinking water supply
2010, Oct. 4 Kolontár, Hungary
(Aerial View: Google Maps external link)
MAL Magyar Alumínium external link bauxite tailings dam failure (view details) 700,000 cubic metres of caustic red mud several towns flooded, 10 people killed, approx. 120 people injured, 8 square kilometres flooded
2010, Jun. 25 Huancavelica, Peru Unidad Minera Caudalosa Chica ? tailings dam failure 21,420 cubic metres of tailings contamination of río Escalera and río Opamayo 110 km downstream
2009, Aug. 29 Karamken, Magadan region, Russia ? gold tailings dam failure after heavy rain
(see background info external link – SRIC 2004)
? eleven homes were carried away by the mudflow; at least one person was killed
2009, May 14 Huayuan County, Xiangxi Autonomous Prefecture, Hunan Province, China ? manganese tailings dam failure (capacity: 50,000 cubic metres) ? The landslide set off by the tailings dam failure destroyed a home, killing three and injuring four people.
2008, Dec. 22 Kingston fossil plant, Harriman, Tennessee, USA Tennessee Valley Authority external link coal ash retention wall failure Release of 5.4 million cubic yards [4.1 million cubic metres] of ashy slurry The ash slide covered 400 acres [1.6 square kilometres] as deep as 6 feet [1.83 metres]. The wave of ash and mud toppled power lines, covered Swan Pond Road and ruptured a gas line. It damaged 12 homes, and one person had to be rescued, though no one was seriously hurt.
2008, Sep. 8 Taoshi, Linfen City, Xiangfen county, Shanxi province, China Tashan mining company iron Collapse of a waste-product reservoir at an illegal mine during rainfall ? A mudslide several metres high buried a market, several homes and a three-storey building. At least 254 people are dead and 35 injured.
2006, Nov. 6 Nchanga, Chingola, Zambia Konkola Copper Mines Plc (KCM) external link
(51% Vedanta Resources plc external link)
copper failure of tailings slurry pipeline from Nchanga tailings leaching plant to Muntimpa tailings dumps ? Release of highly acidic tailings into Kafue river; high concentrations of copper, manganese, cobalt in river water; drinking water supply of downstream communities shut down
2006, April 30 near Miliang, Zhen’an County, Shangluo, Shaanxi Province, China Zhen’an County Gold Mining Co. Ltd. gold tailings dam failure during sixth upraising of dam ? The landslide buried about 40 rooms of nine households, leaving 17 residents missing. Five injured people were taken to hospital. More than 130 local residents have been evacuated. Toxic potassium cyanide was released into the Huashui river, contaminating it approx. 5 km downstream.
2005, April 14 Bangs Lake, Jackson County, Mississippi, USA Mississippi Phosphates Corp. external link phosphate phosphogypsum stack failure, because the company was trying to increase the capacity of the pond at a faster rate than normal, according to Officials with the Mississippi Department of Environmental Quality (the company has blamed the spill on unusually heavy rainfall, though) approx. 17 million gallons of acidic liquid (64,350 m3) liquid poured into adjacent marsh lands, causing vegetation to die
2004, Nov. 30 Pinchi Lake, British Columbia, Canada Teck Cominco Ltd. external link mercury tailings dam (100-metres long and 12-metres high) collapses during reclamation work 6,000 to 8,000 m3 of rock, dirt and waste water tailings spilled into 5,500 ha Pinchi Lake
2004, Sep. 5 Riverview, Florida, USA Cargill Crop Nutrition external link phosphate a dike at the top of a 100-foot-high gypsum stack holding 150-million gallons of polluted water broke after waves driven by Hurricane Frances bashed the dike’s southwest corner 60 million gallons (227,000 m3) of acidic liquid liquid spilled into Archie Creek that leads to Hillsborough Bay
2004, May 22 Partizansk, Primorski Krai, Russia Dalenergo coal ash A ring dike, enclosing an area of roughly 1 km2 and holding roughly 20 million cubic meters of coal ash, broke. The break left a hole roughly 50 meter wide in the dam. approximately 160,000 cubic meters of ash The ash flowed through a drainage canal into a tributary to the Partizanskaya River which empties in to Nahodka Bay in Primorski Krai (east of Vladivostok).
For details download Sept. 2004 report external link (PDF) by Paul Robinson, SRIC
2004, March 20 Malvési, Aude, France Comurhex (Cogéma/Areva) decantation and evaporation pond of uranium conversion plant dam failure after heavy rain in preceding year (view details) 30,000 cubic metres of liquid and slurries release led to elevated nitrate concentrations of up to 170 mg/L in the canal of Tauran for several weeks
2003, Oct. 3 Cerro Negro, Petorca prov., Quinta region, Chile Cia Minera Cerro Negro copper tailings dam failure 50,000 tonnes of tailings tailings flowed 20 kilometers downstream the río La Ligua
2002, Aug. 27 / Sep. 11 San Marcelino, Zambales, Philippines Dizon Copper Silver Mines, Inc. overflow and spillway failure of two abandoned tailings dams after heavy rain (view details) ? Aug. 27: some tailings spilled into Mapanuepe Lake and eventually into the Sto. Tomas River
Sep. 11: low lying villages flooded with mine waste; 250 families evacuated; nobody reported hurt so far
2001, Jun. 22 Sebastião das Águas Claras, Nova Lima district, Minas Gerais, Brazil Mineração Rio Verde Ltda iron mine waste dam failure (view details) ? tailings wave traveled at least 6 km, killing at least two mine workers, three more workers are missing
2000, Oct. 18 Nandan county, Guangxi province, China ? ? tailings dam failure ? at least 15 people killed, 100 missing; more than 100 houses destroyed
2000, Oct. 11 Inez, Martin County, Kentucky, USA Martin County Coal Corporation (100% A.T. Massey Coal Company, Inc. external link, Richmond, VA (100% Fluor Corp. external link)) coal tailings dam failure from collapse of an underground mine beneath the slurry impoundment (view details) 250 million gallons (950,000 m3) of coal waste slurry released into local streams About 75 miles (120 km) of rivers and streams turned an irridescent black, causing a fish kill along the Tug Fork of the Big Sandy River and some of its tributaries. Towns along the Tug were forced to turn off their drinking water intakes.
2000, Sep. 8 Aitik mine, Gällivare, Sweden Boliden Ltd. external link copper tailings dam failure from insufficient perviousness of filter drain (view details) release of 2.5 million m3 of liquid into an adjacent settling pond, subsequent release of 1.5 million m3 of water (carrying some residual slurry) from the settling pond into the environment
2000, Mar. 10 Borsa, Romania Remin S.A. tailings dam failure after heavy rain 22,000 t of heavy-metal contaminated tailings contamination of the Vaser stream, tributary of the Tisza River.
View Romanian Govt. report external link · UNEP report external link (527k PDF)
2000, Jan. 30 Baia Mare, Romania Aurul S.A. (Esmeralda Exploration external link, Australia (50%), Remin S.A. (44.8%)) gold recovery from old tailings tailings dam crest failure after overflow caused from heavy rain and melting snow (view details) 100,000 m3 of cyanide-contaminated liquid contamination of the Somes/Szamos stream, tributary of the Tisza River, killing tonnes of fish and poisoning the drinking water of more than 2 million people in Hungary
1999, Apr. 26 Placer, Surigao del Norte, Philippines Manila Mining Corp. (MMC) gold tailings spill from damaged concrete pipe 700,000 tonnes of cyanide tailings 17 homes buried, 51 hectares of riceland swamped
1998, Dec. 31 Huelva, Spain Fertiberia external link, Foret phosphate dam failure during storm (view details) 50,000 m3 of acidic and toxic water
1998, Apr. 25 Los Frailes, Aznalcóllar, Spain Boliden Ltd. external link, Canada zinc, lead, copper, silver dam failure from foundation failure (view details) 4-5 million m3 of toxic water and slurry thousands of hectares of farmland covered with slurry
1997, Dec. 7 Mulberry Phosphate, Polk County, Florida, USA Mulberry Phosphates, Inc. external link phosphate phosphogypsum stack failure 200,000 m3 of phosphogypsum process water biota in the Alafia River eliminated
1997, Oct. 22 Pinto Valley, Arizona, USA BHP Copper external link copper tailings dam slope failure external link 230,000 m3 of tailings and mine rock tailings flow covers 16 hectares
1996, Nov. 12 Amatista, Nazca, Peru ? ? liquefaction failure of upstream-type tailings dam during earthquake more than 300,000 m3 of tailings flow runout of about 600 meters, spill into river, croplands contaminated
1996, Aug. 29 El Porco, Bolivia Comsur (62%), Rio Tinto external link (33%) zinc, lead, silver dam failure 400,000 tonnes 300 km of Pilcomayo river contaminated
1996, Mar. 24 Marcopper, Marinduque Island, Philippines Placer Dome Inc. external link, Canada (40%) copper Loss of tailings from storage pit through old drainage tunnel 1.6 million m3 Evacuation of 1200 residents, 18 km of river channel filled with tailings, US$ 80 million damage
1995, Dec. Golden Cross, New Zealand Coeur d’Alène external link, Idaho, USA gold Dam movement of dam containing 3 million tonnes of tailings (continuing) (view details external link) Nil (so far) Nil (so far)
1995, Sep. 2 Placer, Surigao del Norte, Philippines Manila Mining Corp. gold Dam foundation failure 50,000 m3 12 people killed, coastal pollution
1995, Aug. 19 Omai, Guyana Cambior Inc. external link, Canada (65%), Golden Star Resources Inc., Colorado, USA (30%) gold tailings dam failure from internal dam erosion (preliminary report on technical causation) 4.2 million m3 of cyanide slurry 80 km of Essequibo River declared environmental disaster zone (view details external link)
1994, Nov. 19 Hopewell Mine, Hillsborough County, Florida, USA IMC-Agrico external link phosphate dam failure Nearly 1.9 million m3 of water from a clay settling pond spill into nearby wetlands and the Alafia River, Keysville flooded
1994, Oct. 2 Payne Creek Mine, Polk County, Florida, USA IMC-Agrico external link phosphate dam failure 6.8 million m3 of water from a clay settling pond majority of spill contained on adjacent mining area; 500,000 m3 released into Hickey Branch, a tributary of Payne Creek
1994, Oct. Fort Meade, Florida, USA Cargill external link phosphate ? 76,000 m3 of water spill into Peace River near Fort Meade
1994, June IMC-Agrico, Florida, USA IMC-Agrico external link phosphate Sinkhole opens in phosphogypsum stake ? Release of gympsum and water into groundwater
1994, Feb. 22 Harmony, Merriespruit, South Africa Harmony Gold Mines gold Dam wall breach following heavy rain 600,000 m3 tailings traveled 4 km downstream, 17 people killed, extensive damage to residential township
1994, Feb. 14 Olympic Dam, Roxby Downs, South Australia WMC Ltd. copper, uranium leakage of tailings dam during 2 years or more release of up to 5 million m3 of contaminated water into subsoil ?
1993, Oct. Gibsonton, Florida, USA Cargill external link phosphate ? ? Fish killed when acidic water spilled into Archie Creek
1993 Marsa, Peru Marsa Mining Corp. gold dam failure from overtopping ? 6 people killed
1992, Mar. 1 Maritsa Istok 1, near Stara Zagora, Bulgaria ? ash/cinder dam failure from inundation of the beach 500,000 m3 ?
1992, Jan. No.2 tailings pond, Padcal, Luzon, Philippines Philex Mining Corp. copper Collapse of dam wall (foundation failure) 80 million tonnes ?
1991, Aug. 23 Sullivan mine, Kimberley, British Columbia, Canada Cominco Ltd external link lead/zinc dam failure (liquefaction in old tailings foundation during construction of incremental raise) 75,000 m3 the slided material was contained in an adjacent pond
1989, Aug. 25 Stancil, Perryville, Maryland, USA ? sand and gravel dam failure during capping of the tailings after heavy rain 38,000 m3 tailings flowside covered 5000 m2
1988, Apr. 30 Jinduicheng, Shaanxi province, China ? molybdenum breach of dam wall (spillway blockage caused pond level to rise too high) 700,000 m3 approx. 20 people killed
1988, Jan. 19 Tennessee Consolidated No.1, Grays Creek, TN, USA Tennessee Consolidated Coal Co. coal dam wall failure from internal erosion, caused from failure of an abandoned outlet pipe 250,000 m3 ?
1988 Riverview, Florida, USA Gardinier (now Cargill external link) phosphate ? acidic spill Thousands of fish killed at mouth of Alafia River
1987, April 8 Montcoal No.7, Raleigh County, West Virginia, USA Peabody Coal Co. (now Peabody Energyexternal link) coal dam failure after spillway pipe breach 87,000 cubic meters of water and slurry tailings flow 80 km downstream
1986, May Itabirito, Minas Gerais, Brazil Itaminos Comercio de Minerios ? dam wall burst 100,000 tonnes tailings flow 12 km downstream
1986 Huangmeishan, China ? iron dam failure from seepage/slope instability ? 19 people killed
1985, July 19 Stava, Trento, Italy Prealpi Mineraia fluorite dam failure, caused from insufficient safety margins and inadequate decant pipe construction
(view details)
200,000 m3 tailings flow 4.2 km downstream at 90 km/h; 268 people killed, 62 buildings destroyed
(view details)
1985, Mar. 3 Veta de Agua No.1, Chile ? copper dam wall failure, due to liquefaction during earthquake 280,000 m3 tailings flow 5 km downstream
1985, Mar. 3 Cerro Negro No.4, Chile Cia Minera Cerro Negro copper dam wall failure, due to liquefaction during earthquake 500,000 m3 tailings flow 8 km downstream
1985 Olinghouse, Wadsworth, Nevada, USA Olinghouse Mining Co. gold embankment collapse from saturation 25,000 m3 tailings flow 1.5 km downstream
1982, Nov. 8 Sipalay, Negros Occidental, Philippines Marinduque Mining and Industrial Corp. copper dam failure, due to slippage of foundations on clayey soils 28 million tonnes widespread inundation of agricultural land up to 1.5 m high
1981, Dec. 18 Ages, Harlan County, Kentucky, USA Eastover Mining Co. coal dam failure after heavy rain 96,000 m3 coal refuse slurry the slurry wave traveled the Left Fork of Ages Creek 1.3 km downstream, 1 person was killed, 3 homes destroyed, 30 homes damaged, fish kill in Clover Fork of the Cumberland River
1981, Jan. 20 Balka Chuficheva, Lebedinsky, Russia ? iron dam failure 3.5 million m3 tailings travel distance 1.3 km
1980, Oct. 13 Tyrone, New Mexico, USA Phelps Dodge external link copper dam wall breach, due to rapid increase in dam wall height, causing high internal pore pressure 2 million m3 tailings flow 8 km downstream and inundate farmland
1979, July 16 Church Rock, New Mexico, USA United Nuclear uranium dam wall breach, due to differential foundation settlement 370,000 m3 of radioactive water, 1,000 tonnes of contaminated sediment Contamination of Rio Puerco sediments up to 110 km downstream
1979 or earlier (unidentified), British Columbia, Canada ? ? piping in the sand beach of the tailings dam 40,000 m3 of ponded water considerable property damage
1978, Jan. 31 Arcturus, Zimbabwe Corsyn Consolidated Mines gold slurry overflow after continuous rain over several days 30,000 tonnes 1 person killed, extensive siltation to waterway and adjoining rough pasture
1978, Jan. 14 Mochikoshi No.1, Japan Mochikoshi Gold Mining Company gold dam failure, due to liquefaction during earthquake 80,000 m3 1 person killed, tailings flow 7-8 km downstream
1977, Feb. 1 Homestake, Milan, New Mexico, USA Homestake Mining Company external link uranium dam failure, due to rupture of plugged slurry pipeline 30,000 m3 no impacts outside the mine site
1976, Mar. 1 Zlevoto, Yugoslavia ? lead, zinc dam failure, due to high phreatic surface and seepage breakout on the embankment face 300,000 m3 tailings flow reached and polluted nearby river
1975, June Silverton, Colorado, USA ? (metal) dam failure 116,000 tonnes tailings flow slide polluted nearly 100 miles (160 km) of the Animas river and its tributaries; severe property damage; no injuries
1975, Apr. Madjarevo, Bulgaria ? lead, zinc, gold rising of tailings above design level caused overloading of the decant tower and collectors 250,000 m3 ?
1975 Mike Horse, Montana, USA ? lead, zinc dam failure after heavy rain 150,000 m3 ?
1974, Nov. 11 Bafokeng, South Africa ? platinum embankment failure by concentrated seepage and piping through cracks 3 million m3 12 people killed in a mine shaft inundated by the tailings; tailings flow 45 km downstream
1974, Jun. 1 Deneen Mica, North Carolina, USA ? mica dam failure after heavy rain 38,000 m3 tailings released to an adjacent river
1973 (unidentified), Southwestern USA ? copper dam failure from increased pore pressure during construction of incremental raise 170,000 m3 tailings traveled 25 km downstream
1972, Feb. 26 Buffalo Creek, West Virginia, USA Pittston Coal external link coal collapse of tailings dam after heavy rain (view Citizens’ Commission report external link) 500,000 m3 the tailings traveled 27 km downstream, 125 people lost their lives, 500 homes were destroyed. Property and highway damage exceeded $65 million. (see details external link)
1971, Dec. 3 Fort Meade, Florida, USA Cities Service Co. phosphate Clay pond dam failure, cause unknown 9 million m3 of clay water tailings traveled 120 km downstream with Peace River, large fish kill
1970 Mufulira, Zambia ? copper liquefaction of tailings, flowing into underground workings some 1 million tons 89 miners killed
1970 Maggie Pie, United Kingdom ? china clay dam failure after raising the embankment and after heavy rain 15,000 m3 tailings spilled 35 meters downstream
1969 or earlier Bilbao, Spain ? ? dam failure (liquefaction) after heavy rain 115,000 m3 major downstream damage and loss of life
1968 Hokkaido, Japan ? ? dam failure (liquefaction) during earthquake 90,000 m3 tailings traveled 150 meters downstream
1967, Mar. Fort Meade, Florida, USA Mobil Chemical phosphate dam failure, no details available 250,000 m3 of phosphatic clay slimes, 1.8 million m3 of water spill reaches Peace River, fish kill reported
1967 (unidentified), United Kingdom ? coal dam failure during regrading operations ? tailings flow covered an area of 4 hectares
1966 (unidentified), East Texas, USA ? gypsum dam failure 76,000 – 130,000 m3 of gypsum flow slide traveled 300 meters; no fatalities
1966 Derbyshire, United Kingdom ? coal dam failure from foundation failure 30,000 m3 tailings traveled 100 meters downstream
1966, Oct. 21 Aberfan, Wales, United Kingdom Merthyr Vale Colliery external link coal dam failure (liquefaction) from heavy rain 162,000 m3 the tailings traveled 600 meters, 144 people were killed (view details external link, watch video external link)
1966, May 1 Mir mine, Sgorigrad, Bulgaria ? lead, zinc, copper, silver, (uranium?) dam failure from rising pond level after heavy rains and/or failure of diversion channel 450,000 m3 the tailings wave traveled 8 km to the city of Vratza and destroyed half of Sgorigrad village 1 km downstream, killing 488 people. (View details external link · historic photographs external link)
1965, Mar. 28 Bellavista, Chile ? copper dam failure during earthquake 70,000 m3 tailings traveled 800 meters downstream
1965, Mar. 28 Cerro Negro No.3, Chile ? copper dam failure during earthquake 85,000 m3 tailings traveled 5 km downstream
1965, Mar. 28 El Cobre New Dam, Chile ? copper dam failure (liquefaction) during earthquake 350,000 m3 tailings traveled 12 km downstream, destroyed the town of El Cobre and killed more than 200 people
1965, Mar. 28 El Cobre Old Dam, Chile ? copper dam failure (liquefaction) during earthquake 1.9 million m3
1965, Mar. 28 La Patagua New Dam, Chile ? copper dam failure (liquefaction) during earthquake 35,000 m3 tailings traveled 5 km downstream
1965, Mar. 28 Los Maquis, Chile ? copper dam failure (liquefaction) during earthquake 21,000 m3 tailings traveled 5 km downstream
1965 Tymawr, United Kingdom ? coal dam failure from overtopping ? tailings traveled 700 meters downstream, causing considerable damage
1962 (unidentified), Peru ? ? dam failure (liquefaction) during earthquake and after heavy rainfall ? ?
1961 Tymawr, United Kingdom ? coal dam failure, no details available ? tailings traveled 800 meters downstream

tonnes = metric tonnes

Note: Due to limited availability of data, this compilation is in no way complete, source Wise-Uranium, image from CBC