Romania + 4 more

Cyanide Spill at Baia Mare Romania - UNEP/OCHA Assessment Mission (Advance copy)



United Nations Environment Programme, UNEP /
Office for the Co-ordination of Humanitarian Affairs, OCHA Assessment Mission

Romania, Hungary, Federal Republic of Yugoslavia

23 February - 6 March 2000


Geneva, March 2000


On 30 January 2000, following a breach in the tailing dam of the Aurul SA Baia Mare Company, a major spill of cyanide-rich tailings waste was released into the river system near Baia Mare in north west Romania. The contaminant travelled via tributaries into the river Somes, Tisza and finally into the Danube before reaching the Black Sea.

Following requests from the Governments of Hungary, Romania and the Federal Republic of Yugoslavia (FRY), and consultations with European Environment Commissioner Margot Wallström and the UN Office for the Co-ordination of Humanitarian Affairs (OCHA), Klaus Toepfer, Executive Director of the United Nations Environment Programme (UNEP), announced on 18 February 2000, that a team of international experts would be sent to the affected area to carry out a scientific analysis of the environmental damage caused by the spill.

The mission was a joint venture of UNEP and OCHA, organised by the Joint UNEP/OCHA Environment Unit, and headed by the Director of UNEP's Regional Office for Europe. Its terms of reference included an independent, scientific description of the spill, the situation and events causing it, the collection and review of data related to the spill and its environmental implications, and the preparation of recommendations for future action and prevention.

1.1 Mission Context

The mission represented a useful model for inter-agency cooperation and multi-disciplinary rapid assessment work.

The mission was limited in size, scope and time, and consequently not intended to provide a full overview of the emergency and its implications. It mainly represented environmental input to a process of international investigation and reviews by, inter alia, the Baia Mare Task Force set up following the visit of European Union (EU) Environment Commissioner Wallström to the area. The results of the assessment mission should be seen in this context, as a starting point rather than the final conclusion. The data and conclusions will have to be refined as further study continues.

1.2 Mission Logistics and Approach

The mission, which lasted from 23 February - 6 March 2000, combined sampling, analysis, interviews with relevant national and local experts, discussions with national authorities, affected populations and local Non Governmental Organisations (NGOs).

Sixteen experts from seven countries (Austria, Czech Republic, Finland, Germany, Norway, Sweden, Switzerland) were selected at very short notice to travel to the affected areas. The composition of the expert group is given in appendix 11.2. The range of expertise included in the team covered chemistry, ecotoxicology, biology, process engineering and dam engineering. In addition to the expert group, a four-person UN Disaster Assessment and Coordination (UNDAC) team from the Disaster Relief Branch of OCHA was dispatched to provide essential logistic and coordination support for the mission. Apart from the mission leader, UNEP's Regional Office for Europe provided a Press Officer and a Scientific Coordinator. The mission also included representatives of the World Health Organization, the UN Economic Commission for Europe, and the European Commission delegations in Romania and Hungary.

The mission had at its disposition three mobile/portable laboratories, provided by the Governments of Germany, Switzerland and the Czech Republic.

Backstopping was provided by the Joint UNEP/OCHA Environment Unit, as well as by the Field Coordination Support Unit (FCSU) and the Military and Civil Defence Unit (MCDU) of OCHA's Disaster Response Branch in Geneva with technical advice being provided by mining specialists in the UNEP Division of Technology, Industry and Economics in Paris. Considerable logistical and other support was also received from the UN Development Programme (UNDP) office in Bucharest, the UN Liaison Office (UNLO) in Croatia and the OCHA Office in Belgrade.

During the entire mission, contacts were maintained and consultations held, in writing and by phone, with representatives of the International Commission for the Protection of the Danube River (ICPDR), the Regional Environmental Center (REC), the Worldwilde Fund for Nature (WWF), donor countries and others. With respect to its work in the Federal Republic of Yugoslavia, the mission received valuable advice and support from the UNEP/United Nations Centre for Human Settlements (UNCHS) Balkans Task Force.

The team assembled in Bucharest in Romania, then traveled to the breach site in Baia Mare before crossing the border into Hungary and followed the river system down to the FRY border. Finally, sampling was undertaken along the Danube in the FRY. Through a specific sampling at the mouth of the Danube the team managed to capture evidence of the spill. Maps of the area indicating the routing and sampling work of the mission can be found in appendix 11.1.

The mission divided into seven key areas of investigation :

  • Dam site construction and management to understand how the breach occurred

  • Emergency planning and early warning systems

  • Drinking water implications for communities potentially affected by contamination of groundwater wells and public drinking water supplies

  • Surface water quality including chemical, biological and ecotoxicological impacts

  • Sediment and soil impacts, especially with regard to heavy metal releases

  • Sampling and analytical methods employed by different local and national authorities to examine potential discrepancies in the measurement of contamination · Interviews and contacts with local authorities, NGOs and representatives of the population to assess the social and economic context and implications of the spill

This report has been produced to provide an overview of the key findings of the mission. Subsequent specialist information detailing analytical methods and findings will be available on a special website, already established by UNEP, to allow the public authorities, industry and the public at large to follow the evolution of events and to gain a better understanding of the technical issues involved in the use of mining, emergency response procedures, etc. The site can be found on

1.3 Acknowledgements

The mission is grateful for the full and open support of the national and local authorities in each of the countries visited. Without such access to good offices, facilities, experts, information and logistic support, the mission would not have been possible. Furthermore, the support provided by the UNDP office in Bucharest and OCHA in FRY also proved essential, as well as the assistance of the Water Research Institute in the Czech Republic, THW in Germany, the Swiss Disaster Relief together with the Swiss Agency for the Environment and AC-Laboratorium Spiez, the Swedish Rescue Services Agency together with the Royal Institute of Technology and the Swedish Environment Research Institute, the Austrian Ministry of Interior, the Finnish Environment Institute, and the Norwegian Institute for Water Research.UNEP/Global Resource Information Database (GRID)-Geneva provided valuable maps of the area and the course and particulars of the cyanide spill.

The mission is grateful for the support it received, in cash and in kind, from Austria, Czech Republic, Finland, Germany, Norway, Sweden, Switzerland and the United Kingdom.


2.1 The Extraction Process

AURUL is a stock company, jointly owned by Esmeralda, Exploration Limited, Australia, and the Romanian Compania Nationala a Metalelor Pretiosasi si Neferoase (REMIN), established in 1992. The company processes solid wastes from earlier mining activity to recover precious metals, especially gold and silver. In 1993 the company obtained an environmental permit from the Ministry of Waters, Forests and Environmental Protection. In 1997, after receiving the Site Construction Permit from the Maramures County Council, construction of the recovering plant commenced. In 1999 the operational permit, based on documentation contained in an environmental impact assessment (EIA), was obtained. The company started operation in May 1999 by processing an existing 30 year-old tailing dam (Meda dam) located near Baia Mare city, to the west, close to the residential area.

The source of the raw materials utilized by the Aurul company is of mining residues accumulated in the Meda tailing dam. These solid wastes resulted from former gold and silver extraction. The technology introduced by Aurul utilizes high concentrations of free cyanide in the process waters for the extraction of the precious metals. The whole process is designed to operate in closed circuit with the cyanide containing waters being re-used, after solids sedimentation in the Aurul pond.

Aurul provided new jobs (150 Romanians directly or indirectly employed and 200 jobs being created during the construction phase) and investments into the Baia Mare mining area, which is experiencing high unemployment. The carbon-in-pulp (Clearing in Place) technology was used for the first time in Romania for precious metals recovery. This technology is capable of recovering gold and silver from tailings containing low contents of precious metals originating from previous production processes of ores. The major tailing dams planned to be mined were:

  • Sasar (Meda dam): 4.43 million tons with a recoverable gold grade of 0.60 g gold per ton
  • Central Flotation: 10.05 millions tons with a recoverable gold grade of 0.48 g gold per ton
  • Old Bozanta: 8.5 million tons with a recoverable gold grade around 0.30 g gold per ton

The precious metal treatment plant of Aurul was designed with a throughput capacity of 2.5 million tons per year. The whole project would produce approximately 1.6 tons of gold and 9.0 tons of silver per year.

The project was to have an effective life span of 10-12 years although this may increase with the addition of resources resulting from the recent exploration-joint-ventures concluded with the Romanian companies Remin and Cuart.

2.2 Sequence of Events and Responses

Meteorological conditions: on 30 January 2000, there was reportedly: 60-70 cm accumulated snow in the pond; 30-liters/square meter precipitation (solid and liquid); and a temperature which rose above 0 °C .

On 30 January 2000 at 11 p.m., the company informed EPA Baia Mare about "incidents" at the technical installations; a field observation showed that because of the high level of the waters long in the Aurul pond, the dam had overflowed and washed away a stretch around 25 meters and 2.5 meters deep. About 100,000 cubic meters of tailings water containing free cyanide and cyanide complexes were released and reached the surrounding areas and the Lapus river; the company shut down the activity and started to close and seal the breach.

On 31 January 2000, the company treated the spillage, which had decreased to 50 L/s with sodium hypochloride in order to neutralize the cyanide. The National Mining Company REMIN started the intake of the remaining water into its active tailing dam located close to the Aurul tailing dam.

On 31 January 2000, EPA Baia Mare established the County Commission for the Defense against Disasters under the coordination of the Prefect of the Maramures County; the water authorities started frequent monitoring of the water quality in the Lapus and Somes rivers. The authorities in Hungary and other downstream countries were informed.

On 1 February 2000, experts from the National Commission for the Safety of Dams arrived to diagnose the causes and suggest possible technical solutions.

On 2 February 2000, at 1:30 a.m., the spillage from the Aurul tailing dam was stopped, and the decontamination of the affected area, around 14 ha, starts; EPA Baia Mare explored legal action against Aurul Co. while in Satu Mare a first report on dead fish was recorded.

On 8 February 2000, experts from Romania and Hungary met in the field and after that in Satu Mare City for a technical evaluation of the impact; eight individual wells contaminated with cyanides were found in Bozanta Mare village.

On 10 February 2000, a meeting between the Hungarian Environment Minister Pal Pepo and Romanian Secretary of State for the Environment, Anton Vlad, takes place.

On 17 February 2000, Mrs. Margot Wallström, EU Commissioner for Environment, the Romanian Environment Minister Romica Tomescu, Mr. Fotion Fotiadis, Head of the European Commission delegation in Romania, and Hungarian Environment Minister Pal Pepo met and visited the site of the accident.

On 25 February 2000, the UNEP/OCHA mission started its assessment work in accordance with formal requests from the three affected countries.

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