UNITED NATIONS OFFICE FOR THE COORDINATION OF HUMANITARIAN AFFAIRS - OCHA-Online
In January and February heavy rains in the mountain area of Northern Chile caused a serious flooding situation in the Second Region. In a man-made dam along the Loa River, Tranque Sloman, the water-level rose with two meter and dead fishes were found. Large amounts of foam was visible all the way from Calama to the Pacific and brownish water was observed as well.
In April The Joint UNEP/DHA Environment Unit in Geneva was requested by the Chilean National Authorities of assistance in connection with the acute pollution of the Loa River. The Swedish Government nominated two national experts that should carry out the required assessment on behalf of UNDHA Relief Co-ordination Branch and Joint UNEP/DHA Environment Unit.
The mission was an assessment and fact-finding mission and the main objective was to make recommendations on both short- and long-term measures to be taken with regard to the consequences of the incident. The mission was carried out within two weeks and most of the time was spent in different meetings with national and regional authorities, experts and representatives from private companies. Also a field-visit to one area was included in the mission.
A large set of data from analyses and statements have resulted in a number of reports aiming at describing and explaining the Loa River incident. However, the generated information does not explain the colour, the foam or what has caused the death of the fishes. An anthropogenic explanation has not been demonstrated and It is not unlikely that the observed and measured situation has a natural explanation.
During the incident itself, and later on, neither the authorities, the public or the scientific representatives have reached a consensus in what has caused the incident, or how this or future similar events should be detected. The immediate phase of the incident also showed a lack of co-ordination between different organisations and levels which delayed the processing of information on the incident.
Recommendations:
TABLE OF CONTENTS
1.1 THE SITUATION
1.2 ACTIONS BY REGIONAL AND NATIONAL AUTHORITIES
2. THE UN EXPERT ASSESSMENT MISSION
2.1 MISSION OBJECTIVES
2.2 ACTIVITIES
2.3 GENERAL OBSERVATIONS
3.1 AVAILABLE DATA
3.2 NOT AVAILABLE DATA
3.3 FIELD OBSERVATIONS
3.4 SUGGESTED SCENARIO
3.5 REFERENCES
6.1 ENVIRONMENTAL MONITORING PROGRAMME
6.1.1 What is environmental monitoring?
6.1.2 General goals for environmental monitoring
6.1.3 Different perspectives of environmental goals
6.1.4 Designing an environmental monitoring system
6.1.5 Implementing an environmental monitoring system
6.1.6 International co-operation6.2 PREPAREDNESS & RESPONSIBILITIES
6.2.1 Responsibilities
6.2.2 The Ten-Step Approach
6.2.3 Risk Management
6.2.4 Contingency Plan
The western border of Chile is the Pacific Ocean, while the eastern is the Andes mountain ridge. The physical climate ranges from (an)arctic in the very south to arid in the north at the border to Peru. In the northern part, sparse deposition and large evaporation result in desert like conditions. The country is organised, from north to south, into 13 administrative regions. With its main stretching in region II, the River Loa enters the Pacific ocean at the border between region I and II. The River Loa is approximately 400 km long and the vertical descent is more than 4 km. The river bed is generally cut deeply into varying and sometimes loosely consolidated geological material, of intrusive, volcanic and sedimentary origin. Volcanoes and hydrothermal systems with geysers, are found in the area.
The air in the mountain region at high altitude contains large amount of moist In January-February 1997 heavy rain fell over the mountain areas between Bolivia and Chile ("Bolivian winter"). Large amounts of water caused the water levels in the River Loa to rise over its normal levels. Still water ponds and vegetation were, often wildly, flushed down the river course. Three distinct features were observed; dark water, large amounts of foam and, at one place, dead fishes.
Frequently occurring metal- and metalloid-bearing oxidic and sulfidic mineralisations, as well as evaporites, makes the area rich in natural resources Several, in an international perspective, very large copper mines are operated, has been in operation or will be put in operation in the area. The largest mine in the area, The Chuquicamata Mine, own by the national Codelco company, is located close to the town Calama. Further towards the Ocean, several excavators of salts from evaporites are active, or have been active.
The River Loa water has a very high natural arsenic concentration, and is not suitable to drink without pre-treatment. A large water treatment plant (ESSAN) is located outside the city of Calama and supplies the Second Region with drinking water. The often very large concentrations of also other metals and macro constituents, as well as other physical and chemical parameters in the river water is monitored by the local authorities in the region.
The water discharge rate in River Loa is small and the waters in the river beds are generally shallow and covered by dense vegetation of emergent reed-like macrophytes surrounded by small still water ponds.
At about 3/5 of the river stretching from the source area to the river mouth a large dam, Tranque Sloman, is located. The dam was built in 1911 for hydro-power generation but has not been in operation for many years. However, the dam is considered as a national heritage. In the dam, large amount of sediments are trapped. How large amounts and what they contain, is not known.
Occasionally, heavy rains over the mountain region in the east causes the river Loa bed to flood. One of these rains took place in january-february, 1997. Heavy rains with, apparently, effects similar to those of 1997 have been reported e.g. 1977, 1986 and 1995.
Environmental issues of neither anthropogenic or natural origin have been in focus of the Chilean authorities and are not specifically treated in legislation.
In January-February 1997 heavy rain fell over the mountain areas between Bolivia and Chile ("Bolivian winter"). Large amounts of water caused the water levels in the River Loa to rise over its normal levels. Still water ponds and vegetation were, often wildly, flushed down the river course. Three distinct features were observed; dark water, large amounts of foam and, at one place, dead fishes.
The event with the observed features resulted in febrile activities amongst the local authorities, however, with a pronounced lack of co-ordination. Samples were taken from the river water and various analyses were made. The different involved parties could not reach a consensus in what had happened or in what the causes were.
1.2 ACTIONS BY REGIONAL AND NATIONAL AUTHORITIES
On March 11, the caretaker of the Tranque Sloman reported to the local police station in Maria Elena about the existence of foam, dark water and dead fishes. The police then alerted the health authorities in Antofagasta about the situation and a few days later the first samples of the water was taken by the Northern Catholic University of Antofagasta. Also the University of Antofagasta was informed about the situation and during the first weekend some complimentary water samplings were made by university people. No samples of the dark water, the foam or the dead fishes were collected or analysed.
The Intendent of the Second Region was informed immediately on March 11 and did co-ordinate all actions from that day. Weekly meetings were held at his office and most agencies and authorities attended these meetings. There was a reported lack of co-ordination, especially regarding the collection of samples. No adjustments of the usual sampling and analytical strategy was made and the samples that were collected and analysed only reflected the normal work of the authority. As a consequence of this, there is still no validated explanation why the water was dark, what the foam consisted of, or why the fishes died.
During the period from March 11 until June 3, several press-conferences were given and lots of explanations to the Tranque Sloman phenomena were presented. However, since there wasn’t any inviolable single explanation the different opinions about the cause, and guilt, lasted for long. The cause, and who is responsible, is still a question of concern, at least in the Second Region.
On the national level, three organisations, or authorities, dealt with the event; ONEMI, CONAMA and Ministry of Health. Probably there is others as well.
During the Rio Loa incident, ONEMI both monitored the situation in First and Second Region and gave co-ordinating support. CONAMA participated in the collection of samples and also collected and processed information from different institutions. In May, ONEMI and CONAMA sat together in meetings and work-shops in order to establish a future way of dealing with similar situations.
There was a distinct difference in the way the incident was treated on regional and national levels. The regional level was a lot more "here and now"-oriented and the national level more future-oriented.
2. THE UN EXPERT ASSESSMENT MISSION
Following the situation in Rio Loa, the Joint UNEP/DHA Environment Unit was requested by the Chilean National Authorities (ONEMI) to provide urgent assistance in assessing the acute "pollution" of Rio Loa and to make recommendations on necessary measures to be taken. The Swedish Government nominated two national experts who should carry out the mission on behalf of UNDHA Relief Co-ordination Branch and the Joint UNEP/DHA Environment Unit.
The main objective of the mission was to assess the situation and to make recommendations on present and future measures to be taken.
The UN Mission Team Members were:
Mr Per Widlundh
Dr Per Östlund
The objectives of the UN Mission included the following
Mon, May 26
Arrival at Santiago.
Briefing by ONEMI.
Tue, May 27
Meeting with UNDP and UNEP
representatives.
Meeting at CONAMA.
Review of documentation and analytical data.
Wed, May 28
Meeting with different authorities and
organisations at ONEMI. Presentation and discussion of different
theories of the cause.
Workshop at CONAMA regarding future planning.
Thu, May 29
Travelling to Antofagasta.
Fri, May 30
Meeting with regional authorities and organisations. In- deep presentation of test results from different laboratories.
Sat, May 31
Field-trip to Tranque Sloman and different rivers. Interviews with local experts and eye-witnesses.
Sun, June 1
Visit to Geyser area (suggested major
arsenic source area), Rio Salado, Rio San Pedro and other sites.
Meeting with CODELCO representatives on-site.
Meeting with ESSAN representative on-site.
Mon, June 2
Meeting with Intendent of Second Region.
Press-conference.
Tue, June 3
Travelling to Santiago.
Meeting with National Commission for Environmental Issues.
Meeting with four senators.
Wed, June 4
Meeting with ONEMI.
Press conference.
Thu, June 5
Office-work.
Travelling to Sweden.
Three principally different explanations for the observed phenomena with dark water, foam and dead fishes in the area have been suggested.
In order to distinguish suggested explanation 1 from 2, two different types of tracers are needed: i) specific components typical for natural processes, and ii) specific components typical for anthropogenic processes. These components must be in sufficient amounts and stable enough for proper analyses. They must not be produced or used by both man and nature, alternatively produced or used, in amounts that are possible to distinguish from each other. Otherwise, only speculations can be made.
The evaluation is based on data presented the UN team during the visit in Chile. As a consequence, the UN team had no influence over the data, not in terms of what kind of data that had been collected or why the data had been collected. The data was generally presented the team together with neither an estimate of its accuracy or its precision. Moreover, the team has very little knowledge about sampling or analytical strategies or methods. Large uncertainties in comparing and evaluating the data and observations are therefor obvious. In some cases, different data generating organisations had not agreed on used methods or results. With this situation in mind, a lot of data has been excluded from the evaluation.
The bulk amount of data has been generated from river water analyses. Also a limited number of sediment analyses had been made. This data was generally focused on metals, metalloids and macro-constituents of the river water. The data appears, in general, to be of good quality and gives an adequate picture of the inorganic scenario in the river water during and, especially after, the event. Both the river discharge volumes and concentrations has later successively decreased to normal levels.
The most obvious needed information would have been detailed analytical data on the dark water and foam. Also an autopsy of the dead fishes would have been of interest. In order to reconstruct the past event different typed of information would have been of importance. This data includes information on the geohydrology in the area. Also air emission/deposition data would be of great importance, especially when considering the possible sources of air emissions in the area, e.g. volcanoes and open pit mining activities. Soil samples representing accumulated atmospheric deposition would have been important. In order to monitor biological effects uptake and accumulation, as well as toxicological effects, biological samples with subsequent suitable analytical parameters would be of interest. Some of the river constituents, e.g. arsenic, may exist in different chemical forms with different chemical properties and biological effects. Such data would be of interest. Worries for an athropogenic cause have been risen at several time points. Among the suggested polluters some focus has been directed towards the mining enterprises in the area. However, from the presented data it is not possible to discuss an eventual anthropogenic explanation for the noted observations. Whether an anthropogenic input is needed or not to explain the found observations, is discussed in the following.
As part of the evaluation process a field trip was made. The trip included a visit to Tranque Sloman, a large geyser area which is suggested to be the major arsenic source area, Rio Salado, and Rio San Pedro. Meetings were held with personnel at the Chuquicamata mine and at the ESSAN water treatment plant outside Calama. A lot of information was gathered from direct observations of the river system, as well as from discussions with responsible people at the different sites. Key information was obtained during discussions with personnel at the ESSAN plant. For instance, from notes in the production log book it came clear that the foaming dark water was first observed in water from inlet pipes from a site close to the city of Lequena, upstream the influence area of anthropogenic activities. A sample of dark water from March 10 was collected by ESSAN and demonstrated to the UN-team .
When the heavy rain fell over the mountains, large amounts of water caused the water levels in the River Loa to rise over its normal levels. The flooding was a rapid process and large amounts of water was transported downstream.
After this, a number of observations were made. In the following, the observation are presented without priorities and suggested explanations are give after each observation. All the explanations are to be considered as plausible. However some are slightly speculative but still possible, for the simple reason that indisputable data is missing.
Observation:
The measured enhanced river water content of metals and other constituents.
Explanations
The rain came after a dry period. The water that was flooding the river carried large amounts of metals, metalloids and other dissolved or particulate inorganic species, mobilised from mineral weathering in the drainage area as well as in the river bed. Probably all measured components have the same principle source, the geological material.
Observation
The dark brow coloured water.
Explanation
In the river beds, large amounts of dark coloured still standing pond water containing large amounts of extensively and partly decomposed organic matter was flushed down the river course. As a pre-treatment step at the ESSAN plant, chlorine is added the inlet water in order to adjust the ionic properties of the constituents in the incoming water before flocculation with iron. The amount of added chlorine is direct proportional to the amount of dissolved organic matter in the water. At the time point when the dark foaming water was entering the plant extremely large amounts of Chlorine were needed. The water inlets were later shut.
An eye-witness reported an "oily shine" on the surface of the Sloman Tranque water, "but without the smell of oil, gasoline, diesel, or similar products", together with a "swampy - muddy smell" without traces of the smell of rotten eggs. Shines are often formed by oxidised iron in the form of iron hydroxy-oxides. The typical smell of swamps and organic mud is caused by decomposing organic matter.
The erosive effect of flushing water is extensive and fine particulate suspended matter may very well be transported downstream the river. Suspended matter adds to the observed opaque colour.
Observation
Foam
Explanation
During microbial metabolisation of organic matter, large amounts of surface active substances, such as proteins and polysaccharides are produced and set free. A typical feature of nutrient rich limnic water systems is the formation of foam. The foam may, in turn be stabilised by the previously mentioned surface active and hydrophobic iron-hydroxy-oxides.
Observation
Dead fishes.
Explanation
Three different causes of death have been suggested; suffocation due to low oxygen levels, osmotic shock due to the enhanced concentrations of inorganic and organic substances and toxification from the enhanced concentrations of organic and inorganic substances, e.g. arsenic. Since an autopsy not was made and since the oxygen level at the time point of death not was measured, any or all of the suggested explanations are equally possible.
Consequently, the opinion of the UN-team is that the observations above can be explained by only natural processes. Eventual but not demonstrated anthropogenic emissions or influences are not needed in order to explain the observations.
A large number of documents, papers, over-head copies and discussions with different people constitute the base for this evaluation. It not possible to list them all. However, the following final reports represent the core of the material:
This was not the first time the Second Region and the Rio Loa was affected by the so called Bolivian Winter. In 1977, 1986 and 1995 heavy rains caused a flooding situation in the lower parts of the region. Foam, brownish water and dead fishes was observed also during these floods. Still, there wasn’t any contingency plan or any prepared way of handling a situation like this on the local or regional level. On the national level an environmental committee, CONAMA, was established in 199?, with the task of co-ordinating all environmental issues within Chile. But CONAMA does not have any operational mandate in case of an emergency.
A lot of time and energy is spent on finding the cause of the foam, dark water and the dead fishes in Tranque Sloman. A large set of data from analyses and statements have resulted in a number of reports aiming at describing and explaining the Loa River incident. However, the generated information does not explain the colour, the foam or what has caused the death of the fishes. During the incident itself, and later on, neither the authorities, the public or the scientific representatives have reached a consensus in what has caused the incident, or how this or future similar events should be detected. From the reports and interviews it is shown that during the immediate phase of the incident there was a lack of co-ordination which probably delayed the processing of information. One of the more severe oversights was that no samples of the foam, dark water or dead fishes were taken. The reason for this may be two:
No real actions were taken at the national level since all responsibilities is within the local or regional level. But since the incident affected both First and Second Region ONEMI was somewhat involved. During a meeting between the two Intendents ONEMI also suggested that an international team should be invited in order to make a more neutral assessment. ONEMI also initiated meetings on the national level between agencies, organisations and institutions that was, or in the future could be, involved in environmental emergencies. The team was invited, and participated, in several meetings and work-shops during its stay in Santiago. CONAMA was also involved in monitoring the situation and collected lots of information and reports from different sources. A CONAMA representative presented a comprehensive amount of data regarding Rio Loa, both before, during and after the incident. CONAMA and ONEMI did co-operate in an efficient way as far as the team understood, both regarding the present situation and future planning and preparedness.
Based on the input of this mission, including review of existing data and information as well as interviews, the following conclusions and recommendations represent the view of the team.
Anthropogenic activities are not needed for the explanation of any of the observed effects.
During the first days of the incident in Tranque Sloman there were several actions taken:
The following recommendations can of course not change what happened in Rio Loa during those weeks in March and April. But it is hoped that by considering the lessons learned and by working in a future-oriented, co-ordinated way environmental emergencies, if not avoided, may be less severe.
One short-term and two long-term future activities are recommended.
6.1 ENVIRONMENTAL MONITORING PROGRAMME
Section 6.1 is largely based on Swedish principles for environmental monitoring according to the Swedish Environmental Protection Agency.
6.1.1 What is environmental monitoring?
In general terms, environmental monitoring can be defined as activities where state, trends and effects in the environment are monitored. The activities shall describe the state of the environment in a way that makes it useful for the environmental work and progress. Environmental monitoring shall also see to that the allocated resources get the best possible effects. The environmental monitoring programme does also function as a receipt on that the work leads to positive environmental effects.
Data from environmental monitoring shall make it possible to
At national level, environmental monitoring shall
6.1.2 General goals for environmental monitoring
General goals for environmental monitoring:
Environmental goals are defined in different perspectives.
6.1.3 Different perspectives of environmental goals
Environmental goals are formulated with different perspectives. Some defines best possible state within given financial frames, others best possible environmental state or, alternatively, worst acceptable state. Goals with different perspectives are:
In order to formulate environmental goals, a number of objects that are to be protected need to be defined. These are often defined as i) human health, ii) bio-diversity, iii) natural resources and iv) the natural and cultural landscape.
6.1.4 Designing an environmental monitoring system
Environmental monitoring can not be based on established methods. A systematic development of the programme must be made in order to adapt it to the actual problems, the state of knowledge, adjusted goals and various new technologies must be made. Resources must be allocated for this development process. Available methods and techniques must also be evaluated against each others. The basis of a programme, or a system, are long-time and unbroken series of measurements. Only long-time series of measurements from fixed stations or surfaces can result in trustworthy trends, in state and effects, and where natural variations of stochastic or periodic character can be taken into account. In parallel, it is also important to allocate resources for data base generation and evaluation. All resources cannot be used for analyses according to established methods and periodicity since the ability and alertness for new or rapidly upcoming demands. Examples of such situations are:
The latter two situations without or with known frequency are often referred to as campaigns.
6.1.5 Implementing an environmental monitoring system
The first thing to do is to map the needs and to set priorities on the bases of natural variations, identified environmental threats and objects to be protected. Since several questions often can be answered by one analyses, it is not wise to build up the system around specific questions or threats. In that case, the risk for duplications is obvious. A natural system base is instead the different media involved; air, water and soil, or biotopes.
After a first division of the system into different specific media, further divisions into subgroups may than further clarify the different needed studies and variables. The same measured variable may very well meet the need identified in different subgroups. For example, in the media "water", the variable "chlorinity" may correspond to the need for a variable under the subgroups "water chemistry", "weathering" or "anthropogenic load". Similarly, in the media "air" the variable "sulphate concentrations" may correspond to variables under the subgroups "air chemistry" or "atmospheric deposition". By organising the system under different media and subgroups the risk for duplications can be avoided.
Finally, it is important to base the program on variables and methods that can be agreed on in both a regional, national and international perspective.
6.1.6 International co-operation
Environmental monitoring is influenced, to a large extent, by international conventions and various forms of co-operation in the field of environment. In this connection, references can be made, in particular, to the following conventions:
Relevant co-operation in the framework of UNEP, WHO and WMO should also be taken into account.
6.2 PREPAREDNESS & RESPONSIBILITIES
Like all emergencies and disasters there is a need for a clear and visible organisation during environmental emergencies. But unlike other emergencies as earth-quakes, fires and other "fast-moving" incidents, an environmental emergency is a lot more complex from a command perspective. There are many ministries, agencies, organisations and institutions involved from the very beginning. All of them very competent and skilful within their own domain. This makes the "command situation" during an environmental emergency very sensitive. But still an important question to be solved.
Recommendation: Clarify who, or what organisation, is responsible for the co-ordination and decision-making during an environmental emergency on both national, regional and local level.
The UNEP/APELL (Awareness and Preparedness for Emergencies at Local Level) process, which is well-known in Chile, is an excellent tool which will lead to a useful and effective emergency plan on the local level. Some parts can of course be used on the national level as well.
Recommendation: Implement the APELL Process in all regions and emphasise on the risk evaluation.
The second step in the above described process is "Evaluate the risks and the hazards …". Regarding environmental emergencies a systematic approach can be made in order to identify future risks and incidents. The approach mean certain steps that should be taken one by one.
Recommendation: Decide on a Risk Management model, implement the model by trained Managers on the regional level.
There is a need for a National Environmental Contingency Plan. In this plan a number of headings should be developed. Alert, Organisation, Co-ordination, Responsibilities and Authority, Information, Tactical Guidelines, References are examples of what can be included in such a plan.
The Joint UNEP/DHA Environment Unit in Geneva has at its disposal "Guidelines for the development of a national contingency plan", that could be used in the elaboration of relevant documents.
However, as mentioned under 6.2.1 above, an environmental emergency is a bit special. It is just not enough with a plan, it takes a complete structure if it should be successful. The Operational Elements and Preventive and Policy Implications need to go hand in hand. This could be arranged through a National Co-ordinator. In order to get all authorities, agencies and institutions in the same boat a standing working-group with all parts should be established. This very same group can in an operational situation be an expert-team to the responsible "commander".
The contingency plan concept is applicable on both national, regional and local level and does also fit in very well with the APELL Process and the Risk Management model.
Recommendation: Develop a contingency plan for environmental emergencies on national, regional and local level.
Dr Alberto Maturana Palacios, Director of ONEMI
Magaly Cécenes, CONAMA
Pedro Cardenas Diaz, Environmental Engineer, CODELCO Chile
Evelyn Nielsen Pyke, UNDP - Santiago
Mario Carvajal Cortes, Director of OREMI - 2nd Region
Per-Arne Hjelmborn, Swedish Embassy - Santiago
Prof Ortega, Academico Universidad Catolico del Norte
Prof Roman, Universidad de Antofagasta
Alberto Calbres, ESSAN Water Purification Plant in Calama