Chronology of tailings dam failures in the Philippines (1982-2005)
Last updated: 10 July 2007
Note: Due to the limited availability of data, this is in no way a complete list. A ‘failure’ is taken to mean a collapse, overflow, or leak from the tailings dam, pond, spillway, or associated drainage pipes.
Date Location Company Type of Incident Release Impacts
2007
Jul. 11
Rapu-Rapu,
Albay
Province
Lafayette
Philippines
Inc.
2007
Oct. 31
Rapu-Rapu,
Albay
Province
Lafayette
Philippines
Inc.
2005
Oct. 31
Rapu-Rapu,
Albay
Province
Lafayette
Philippines
Inc.
Heavy rainfall caused the lower tailings storage facility to fill up and so an emergency drainage canal was made which led to overflow of toxic material into the Ungay and Hollowstone creeks
Cyanide levels exceeding
DENR standards by up to 356 times
12
Fish kills occurred on several occasions and affected the costal waters of
Sorsogon and nearly the whole of the Albay gulf.
Presence of toxic heavy metals apparent in the soil, water, sediment samples and in the urine and blood of some of the patients from nearby communities.
12 & 13
Heavy rainfall caused the lower tailings storage facility to fill up and so an emergency drainage canal was made which led to overflow of toxic material into the Ungay and Hollowstone creeks
Cyanide levels exceeding
DENR standards by up to 356 times
12
Fish kills occurred on several occasions and affected the costal waters of
Sorsogon and nearly the whole of the Albay gulf.
Presence of toxic heavy metals apparent in the soil, water, sediment samples and in the urine and blood of some of the patients from nearby communities.
12 & 13
Heavy rainfall caused the lower tailings storage facility to fill up and so an emergency drainage canal was made which led to overflow of toxic material into the Ungay and Hollowstone creeks
Cyanide levels exceeding
DENR standards by up to 356 times
12
Fish kills occurred on several occasions and affected the costal waters of
Sorsogon and nearly the whole of the Albay gulf.
Presence of toxic heavy metals apparent in the soil, water, sediment samples and in the urine
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Chronology of tailings dam failures in the Philippines (1982-2005)
2005
Oct. 11
2004
Nov. 22
Siocon,
Zamboanga del Norte
2002
Sep. 11
2002
Aug. 27
2001
Dec. (to date)
Rapu-Rapu,
Albay
Province
San
Marcelino,
Zambales
San
Marcelino,
Zambales
Sipalay,
Negros
Occidental
Lafayette
Philippines
Inc.
TVI Pacific
Dizon Copper
Silver Mines
Inc. (DCSMI)
Dizon Copper
Silver Mines
Inc. (DCSMI)
Maricalum
Mining Corp. and blood of some of the patients from nearby communities.
12 & 13
Tailings pump failed causing tailing materials to be spilled from an emergency pond of the mill into the gold processing plant and nearby waterways of the Alma and
Pagcolbon creeks
At least 20 cubic metres of slurry material
(containing cyanide beyond the standard of
0.05mg/litre (& likely other toxic heavy metals and chemicals) 12 &
13
2 kg of dead small fish and crustaceans at the shoreline collected on the same day at the location where the affected creeks exit into the sea 13
Suspected unsafe disposal methods of toxic chemicals into the
Lituban River downstream of the mining site
No data available
3 people from the region contracted a fungal infection upon coming in contact with the water from the river.
14 Other noticeable effects have included: deterioration in water quality of the local rivers, unusual siltation, sudden fish kills and diseased fish in the river 15
Spillway of Bayarong tailings dam collapsed during heavy rain
Heavy rains impounded water on the Bayarong tailings dam and Camalca silt dam, and spillways, eroding these and eventually causing leak
Since the ‘temporary’ stoppage of operations no fresh tailings have been discharged, causing tailings pond 3
No data available
No data available
Dust fallout
Low lying villages flooded with mine waste; 250 families evacuated; nobody reported hurt so far 10,11
Some tailings spilled into
Mapanuepe Lake and eventually into the Sto. Tomas
River; dams heavily damaged
(especially
Camalca) 10,11
Highly excessive levels of dust effect area of 5 km; air quality affected; alleged
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Chronology of tailings dam failures in the Philippines (1982-2005)
1999
Aug.
9 to dry up and become prone to wind actions
Toledo City,
Cebu
Atlas
Consolidated
Mining and
Development
Corp.
(ACMDC)
Outlet in drainage tunnel of an open pit
(from closed copper mine) was clogged resulting in loosening of accumulated silt, causing discharge into the Sapangdaku River towards the sea
5.7 million m 3 of acidic water increase in respiratory illnesses in nearby residents 7
Increase in acidity of affected water bodies causing fish kill 9
1999
Apr. 26
Placer,
Surigao del
Norte
Manila Mining
Corp. (MMC)
Tailings spill from damaged concrete pipe in tailings pond 7
700,000 tonnes of cyanide tailings
17 homes buried;
40 hectares affected including
20 hectares of agricultural land
9,10,11
1998
June 27
Sibutad,
Zamboanga del Norte
Philex Gold
Philippines
Inc. (Philex
Mining Corp.)
Heavy rain resulted in overflowing of silt dam at the Sibutad gold project
No data available
Fish kill and blindness 4
1997
Nov. 6
1995
Dec.
Sibutad,
Zamboanga del Norte
Sipalay,
Negros
Philex Gold
Philippines
Inc. (Philex
Mining Corp.)
Philex Gold
Philippines
Heavy rain caused mudflow and rockslide into silt dam at Lalab
Pressure exerted by impounded tailings
No data available
No data available
Flashfloods damaged nearby houses and rice fields 4
1996
Mar. 24
Marinduque
Island
Marcopper
(Placer Dome
39.9%)
The official story is that the rock around the plug in the Tapian Pit drainage tunnel was fractured and the plug failed. However, the tunnel started leaking in August 1995. In
September 1995
Marcopper/Placer
Dome started drilling down 160 meters to the tunnel. On 24
March 1996 the drill hit the tunnel, released an air pocket holding back tailings and started the spill 3
Placer Dome claim a release of 1.6 million m 3 . The real estimate, based on the
United Nations, is between 2-3 million m 3 over the first 4-5 days of discharge alone 3
Evacuation of
1200 residents; 26 km of the
Makulaquit and
Boac river systems filled with tailings rendering them unusable;
US$ 80 million in damage (the real figure is much higher 3 ); flash floods isolated 5 villages; 3
Marcopper managers charged
2,8,9,10
67,000 m 3 of bagged tailings collected and stacked in tattered sacks on banks of
Boac River since cleanup began in summer 2000 1
Siltation of Sipalay
River 9
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Chronology of tailings dam failures in the Philippines (1982-2005)
8 Occidental Inc. (Philex
Mining Corp.) caused leak in decant tower of tailings pond 1 at the Bulawan gold mine
1995
Sep. 2
Placer,
Surigao del
Norte
Manila Mining
Corp. (MMC)
Dam foundation failure at tailings pond 5 of the
Placer copper-gold project
50,000 m 3
1993
Dec. 6
1993
June
26
1992
Jan.
1987
July 9
1986
Oct.
17
1982
Nov. 8
Sipalay,
Negros
Occidental
Maricalum
Mining Corp.
Dam failure at tailings pond 3 due to slippage of foundations on clayey soils at the
Sipalay copper project
27-28 million tonnes
12 people killed; coastal pollution
9,10
Marinduque
Island
Marcopper
(Placer Dome
39.9%)
The Maguila-Guila siltation dam collapsed due to pressure from heavy siltation at the dam wall
No data available
Mogpog River flooded; 2 children killed; livestock killed; agricultural land contaminated; downstream communities and
Mogpog Town flooded 3,5,8
Mankayan,
Benguet
Tubu,
Benguet
Placer,
Surigao del
Norte
Philex Mining
Corp.
Collapse of dam wall at tailings pond 2 due to weakened foundation after the 1990 earthquake near the
Padcal copper project
80 million tonnes
Manila Mining
Corp. (MMC)
Dam failure
Siltation affected government irrigation system
4,9,10
Unknown quantity of cyanide tailings
Fish kill 6
Mankayan,
Benguet
Itogon-Suyoc
Mines
Overtopping at the dam of the Itogon-
Suyoc gold and silver mines occurred during a typhoon when the dam’s penstock and diversion tunnel were blocked
Lepanto
Consolidated
Mining
Corporation
Collapse of tailings pond 3 due to weakened dam embankment caused by additional loading
No data available
No data available
Siltation of the adjoining river
Siltation of the
9
Abra River which affected 9 municipalities 9
Widespread inundation of agricultural land up to 1.5m high; siltation of the
Tao-angan River
9,10 tonnes = metric tonnes
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Chronology of tailings dam failures in the Philippines (1982-2005)
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Chronology of tailings dam failures in the Philippines (1982-2005)
Sources:
Note: Most failures listed have multiple sources, but the main references are listed below.
1. Adraneda, K (2003). Mine tailings still a threat to Boac folk. Dapitan Advocates. dapitan_advocates@yahoogroups.com
2. Buffington, D.L. & Wallis, T. (2001). Financial implications in tailings dam management.
Pincock
Perspectives, No. 24. http://www.hartcrowser.com/PDFs/Issue24-TailingsMgmt.pdf
3. Coumans, C. (2000). Placer Dome.
In, Undermining the forests: The need to control transnational mining companies (a Canadian case study). http://www.minesandcommunities.org/Country/undermining.pdf
4. Fiel, T.N. The impact of Philex mining operations in Sibutad.
http://www.minesandcommunities.org/Company/philex1.htm
5. MacDonald, I. & Brendan, R. (2002). Mining ombudsman annual report 2001-2002.
Oxfam Community
Aid Abroad. http://www.caa.org.au/campaigns/mining/ombudsman/2002/prelimeports/marinduque/request.html
6. Mineral Resources Forum (2002). Cyanide spill incidents 1983-2001.
http://www.mineralresourcesforum.org/incidents/cn_accidents.htm
7. Mining Environment and Safety Division (2002). Maricalum mining operations.
Philippine Mine Safety and Environment Association. http://www.pmsea.org/maricalum
8. Project Underground (2002). A disaster looms for communities in Marinduque, Philippines.
Drillbits
& Tailings, Vol.7, No.24. http://www.moles.org/ProjectUnderground/drillbits/7_04/3.html
9. Ramos, H.C. et al (2000). Tailings dam accidents and the use of chemicals in mining: Issues, policy response and lessons learned from the Philippines. Mines and Geosciences Bureau,
Department of Environment and Natural Resources, Philippines. http://www.mineralresourcesforum.org/workshops/regulators/2000/docs/Ramospdf
10. WISE Uranium Project (2002). Chronology of major tailings dam failures (from 1960).
http://www.antenna.nl/wise/uranium/mdaf.html
11. WISE Uranium Project (2002). The San Marcelino tailings dam spill (Zambales, Philippines).
http://www.antenna.nl/wise/uranium/mdafsm.html
12. Mines & Geosciences Bureau (2006) Rapu-Rapu Fact-Finding Commission Full Report. http://www.mgb.gov.ph/miningissues/rapurapu/issue_rapurapu.htm
13. Department of Environment and Natural Resources (2006) DENR Assessment of the Rapu-Rapu
Polymetallic Project. http://www.mgb.gov.ph/miningissues/rapurapu/rapurapuassessment.pdf
14. Mines & Communities (2005) Siocon Residents Contract Skin Disease from Polluted River. http://www.minesandcommunities.org/Action/press521.htm
15. Mines & Communities (2005) Canadian Mining Expert Finds Conditions Unacceptable at Canatuan
Mining Site. http://www.minesandcommunities.org/Action/press536.htm
Compiled by Philippine Indigenous Peoples Links http://www.piplinks.org
Please send further information on these or any other tailings dam incidents to comms@piplink.org
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