Las poblaciones amerindias de Cuyuni y Mazaruni contaminadas por mercurio ( Guayana Esequiba)

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http://www.stabroeknews.com/2009/news/local/06/28/diminished-mercury-use-in-gold-mining-%E2%80%98inevitable%E2%80%99/


Diminished mercury use in gold mining ‘inevitable’


By Stabroek staff June 28, 2009 in Local News

miners must gear for change
They have been romanticized as lonely men seeking to make their fortune; praised for their contributions to the economy and vilified as destroyers of the environment. And now miners are being swept up in a change many regard as inevitable.


None has made it so clear as Prime Minister Samuel Hinds, who bluntly told miners that they are currently not meeting the standards requir-ed and would have to make a significant change in attitudes and practices and do this rapidly. His statements came at the launch of the Guyana Low Carbon Development Strategy, a plan which outlines Guyana’s approach to promoting economic development in an environmentally sustainable way. A key part of the strategy involves the deployment of Guyana’s rainforest towards addressing global climate change.


President Bharrat Jagdeo has said that mining will continue but it will be “very, very controlled” with minimal impact on the environment.“It can’t be business as usual,” William Woolford, head of the Guyana Geology and Mines Commission (GGMC) told this newspaper.


Miners have “got to change the way” they currently conduct their operations, said Rickford Vieira, the Regional Goldmining Pollution Abate-ment Coordinator at the Guyana Office of the World Wildlife Fund (WWF).Executive Director of the Guyana Gold and Diamond Miners Association (GGDMA) Edward Shields acknowledges that change is inevitable.


In recent times, the gold mining industry has come under increased scrutiny with the use of mercury in operations being of concern to many, particularly those in the environmental sector. The use of mercury, which is toxic to human health and the environment, in gold mining is governed by strict regulations here but compliance is another matter. The chemical is relatively easy to obtain in Georgetown and retails for about $4,200 per pound.


Use of mercury

Mercury is primarily used to create an amalgam with the gold, and is later heated to separate it. In the process of heating, unless a retort is used, the mercury then enters the atmosphere, and precipitates back into the water, from where it enters the ecosystem, and the food chain. A retort is a closed container, which traps and condenses the mercury vapour without releasing it into the atmosphere.


However, some miners use mercury in sluice boxes which eventually leads to the pits being spiked. This system of mercury use is particularly dangerous, as it introduces mercury directly into the water system. Shields admitted that this is being done at present and says that the association has spoken out against it. He noted that it is the miners themselves, who are affected. It is not clear how much mercury is used in the industry annually and Vieira said the WWF uses a “rough ratio” of one gramme of mercury to one gramme of gold produced.


The European Union and the United States have both announced bans on mercury exports from those countries which will come into force in 2011 and 2013 respectively. Shields said he does not believe that the bans will affect local miners, a view that is not shared by Vieira.


Shields declared that miners do not have any special affiliation for mercury. “Mercury is just something that is necessary to amalgam the gold and until such time that there can be a credible alternative to the use of mercury; miners will continue to use mercury,” he said. He asserted that once there is demand and there is heavy demand for it in many parts of the world, if a company cannot manufacture mercury in Europe then it will shift its business elsewhere.

However, Vieira pointed out that the ban means that mercury will not be available in sufficient quantities to sustain the industry.


In the meantime, differences regarding mercury are evident. “In terms of polluting rivers, mercury contaminated rivers and so forth, hundreds of studies have been done in Guyana and to date, there is no study that concludes that mining is the cause of mercury pollution,” Shields said. “You may have noted and found mercury but there is nothing definitive that says that mercury came about because of mining,” he added. He revealed that the Miners Association has viewed some efforts with suspicion as it believes the emphasis on mercury was because persons wanted to stop mining. “It had nothing to do with the health of anybody because the question is always asked, if a person has high concentrates of mercury in his system, what is the next step and to date I am still to get an answer. Do they have medical treatment? Do we go to a doctor? Is there another way of detoxifying the person? There seems to be nobody looks at that.” he declared. He reasons that the pollution and turbidity can be rectified and even eliminated but mercury is not biodegradable and mining would have to cease. “So that is why we were always very suspicious of this emphasis on mercury.”


Long-term effect
Vieira, however, said that studies have proved that mining activities have released mercury into the environment. He referred to a Guyana Environmental Capacity Development Project (GENCAPD) study in 2000, which found that 89%-96% of the population surveyed in Isseneru Village in Region Seven (Cuyuni/Mazaruni) had dangerous levels of mercury contamination. Residents of the community are involved in gold mining and the study found that no one in the village owned a retort, and many kept mercury at home, near sleeping and cooking areas. They also ate more fish than another community that was surveyed. Vieira said tests on persons, who trade in gold and work in an enclosed environment, have revealed high mercury levels. He admits that it is more of an occupational and safety issue but points to another study done in the North-West District, where persons hardly ate any fish, which were largely absent because of the turbidity levels of the rivers, and were only exposed to the mercury through mining.


Long-term effects of mercury poisoning include damage to the brain, nervous system, kidneys and thyroid and Vieira points out that it is important to understand that mercury poisoning is a long-term problem and symptoms don’t show up until years later. He said that exports of mercury were banned precisely because of the harm it could cause and at present the WWF is looking at developing a project proposal with the Ministry of Health to do a health assessment in areas where mercury is shown to be in residents systems. He said that they would give advice on what can be done.


Meantime, Shields referred to another study done by GENCAPD which found that people at Gunn’s Strip had high levels of mercury in their bodies even though no mining is done there. He said people need to realize that mercury occurs naturally. However, he later acknowledged that some miners do not use mercury as they should. “If the laws that apply to the use of mercury in Guyana are applied, it would cut down the amount of mercury being used by almost 70%”, he said. Pointing to the rules that govern the use of the chemical, he said that the message has not been getting out.


But are practices changing and have miners begun exploring mercury-free techniques to recover gold? They have, Shields said. He pointed to several ongoing projects including one current one where environmental officers attached to the GGDMA are working in the field with the GGMC and demonstrating the use of shaking tables to miners in the Mahdia district. He said that he has noticed that priority is now being given by the conservation and environmental agencies, including the WWF, to hands-on projects demonstrating how miners can mine without using mercury or with minimum use of mercury and the association is happy with this. “We are not by definition willing to destroy our own environment. If they come up with a method that could amalgam the gold tomorrow and not use mercury, quickly and easily, some other chemical, then the miner will jump aboard,” he commented.


Renegades

He declared that miners are not very interested in going to a theoretical seminar; on-the-ground demonstrations are the type of help needed.Every industry has renegades, Shields said, stating that mining is a serious business and over 90% of miners want to work in accordance with the laws.

Woolford of the GGMC states that the regulatory agency has an education and awareness programme and officers are in the fields working with miners with respect to different mining methods and using a concentrator to process gold, where mercury is not necessary. A lot of work has been done, he said, adding that meetings have been held and mercury use in small-scale mining, discussed. He admits that there have been problems particularly when there are “shouts” and miners take chances to make money. He said that this calls for a culture change and it cannot be business as usual.


The regulatory agency head pointed out that overall, there is evidence of a positive change of attitude in miners. “The miners have been willing to work with us which is a big change of attitude,” he said.

Vieira said the WWF is working to expose miners to some of the alternatives to mercury use. He said several projects that are being done are part of a strategy to get miners knowledgeable about mercury-free techniques. He said the GGDMA has purchased two pieces of mercury-free equipment: a cyanidation plant and a shaking table, through a grant by the WWF.


But Shields said the problem with alternative methods of processing gold is the cost. He recalled a visit to French Guiana, a trip sponsored by the WWF, where miners were able to observe mercury-free techniques. He said after the use of mercury was banned in that country, a different type of processing system was introduced and miners received help. There are laboratories to process the gold and exploration is done before the actual work commences. And he noted the amount of gold produced in the mines there is significantly higher.


“In our country, hopefully we are working towards a situation where the industry is trying to move away from this hit and miss type of prospecting,” he said adding that miners must do more drilling. He said the GGMC can assist in this regard suggesting that geologists can prospect, report the findings and the GGMC can put out a bulletin, identifying where minerals are located and similar data. He observed that once mining becomes organised in the sense that persons are not mining until they have some idea of what they can get, then they would have no problem investing money in equipment.


It is a view echoed by Vieira, who said that in the future, miners have to look to alternatives. He asserts that amalgamation is not the best way to recover gold and projects are ongoing, with various partners, on making miners aware that the alternatives have higher recovery rates. With regard to cost, he said that not every miner has to invest in equipment; there can be a centralized location for processing. Miners have to start doing exploration, he said and they know this. “They know that the system will evolve into something more competitive, more environmentally-accepted. It has to be like any other business where feasibility studies are done,” Vieira said.



Nota del editor del blog: Al referenciarse a la República Cooperativa de Guyana se deben de tener en cuenta los 159.500Km2, de territorios ubicados al oeste del río Esequibo conocidos con el nombre de Guayana Esequiba o Zona en Reclamación sujetos al Acuerdo de Ginebra dl 17 de febrero de 1966.


Territorios estos sobre los cuales el gobierno Venezolano en representación de la Nación venezolana se reservo sus derechos sobre los territorios de la Guayana Esequiba en su nota del 26 de mayo de 1966 al reconocerse al nuevo Estado de Guyana .
“...por lo tanto, Venezuela reconoce como territorio del nuevo Estado, el que se sitúa al este de la margen derecha del río Esequibo y reitera ante la comunidad internacional, que se reserva expresamente sus derechos de soberanía territorial sobre la zona que se encuentra en la margen izquierda del precitado río; en consecuencia, el territorio de la Guayana Esequiba sobre el cual Venezuela se reserva expresamente sus derechos soberanos, limita al Este con el nuevo Estado de Guyana, a través de la línea del río Esequibo, tomando éste desde su nacimiento hasta su desembocadura en el Océano Atlántico...”

Actualmente en los territorios de la Guayana Esequiba se encuentran entre seis y ocho mil mineros ilegales de nacionalidad brasileña conocidos como Garimpeiros y otros tantos Guyaneses denominados Pork-nockers (mineros ilegales guyaneses) que desbastan las selvas que no han sido controlados lo que hace insegura las aéreas de explotación minera donde ocurren continuos asaltos y asesinatos. Para poder controlar el uso del mercurio primero hay que controlar la minería ilegal, y el comercio del oro.