Tuesday, 17 January 2012

PROSPERITY UNTO DEATH – FACTS ABOUT URANIUM MINING (PART ONE)

Currently, three major exploration companies – African Energy Resources (AER), Denison Mine Zambia Limited (DMZL) and Lumwana Mining Company (LMC) – have acquired concessions for uranium exploration and subsequent mining in Zambia.

AER is operating in the Chirundu area, where it holds a 70% interest in the Chirundu Joint Venture project, with Albidon Limited (ASX: ALB) holding the remaining 30%. The Company is also involved in another venture called the Kariba Valley Joint Venture Project, where it holds a 30% interest, with Albidon Limited holding 70%.

DMZL is currently developing its Mutanga- Dibwe Project located in Siavonga District of Southern Province. LMC uranium mining activities fall within the confines of the Company’s copper exploration and mining operations at Malundwe and Chimiwungo copper, cobalt, gold and uranium deposits 95 km west of Solwezi. So far, these companies have reported findings of commercially viable deposits, with AER and DMZL having delineated some commercial deposits in their Siavonga District concessions, and the latter targets to commence production in 2012. LMC, on the other hand, is already stock-piling uranium ore that comes as a by-product of its copper mining activities.

Uranium is the heaviest naturally occurring element on earth. It is quite widespread in the earth’s crust, but concentrated in certain rock formations. As the uranium atoms slowly disintegrate over time, a host of radioactive by-products are formed – thorium- 230, radium-226, radon-222 and the infamous radon daughters, including lead-210 and polonium-210.

Canada is the world’s largest producer and exporter of uranium. The commercial value and the dangers of uranium are based on two extra-ordinary properties which it possesses and these are: a) radioactivity, and b) that the element is fissionable. The two properties are quite different.
 
Radioactivity
Uranium’s property of radioactivity was discovered by Henri Becquerel in 1896. Afterwards, Marie Curie observed that even after chemically separating uranium from the rest of the crushed rock, the crushed rock remained very radioactive – much more so than the uranium itself. Essentially, most of the radioactive decay products (about 85%) of the uranium remain in the crushed rock, when uranium is separated from the ore. This tallies with the research findings of Marie Curie that most of the radioactivity is left behind in the residues. In her research, Curie discovered that this phenomenon was because of two elements – polonium and radium – that are by-products of uranium.

Radioactive substances have unstable atoms which can, and will explode microscopically, and when they do, they give off a burst of energy (Edwards, 1992). This process is called radioactive disintegration or radioactive decay. When radioactive atoms explode, they give off highly energetic charged particles of two types: alpha and beta. These are particles and not invisible rays. They are like pieces of shrapnel (metal balls) from an explosion. And this microscopic shrapnel does great damage because of the high energy of the particles which are given off. Edwards (1992) explains that when a radioactive atom explodes, that atom is changed permanently into a new substance. And radium turns out to be one of the results of exploding uranium atoms.

Wherever uranium is found on the earth, radium will always be found with it because the latter is one of about a dozen so-called decay products of uranium. When uranium disintegrates it turns into a substance called protactinium, which is also radioactive. And when that disintegrates it turns into a substance named thorium, which is likewise radioactive. When thorium disintegrates it turns into radium; when radium disintegrates it turns into radon gas. And when radon gas atoms disintegrate, they turn into what are called the radon daughters, or radon progeny, of which there are about half a dozen radioactive materials, including polonium. Finally this progression ends up with a stable substance, which in itself is highly toxic – lead.

Fission
In 1938, it was discovered that uranium is not only radioactive, but that it is also fissionable, which makes it unique among all naturally occurring radioactive materials. When uranium atoms undergo the fission process, large amounts of energy are released. Unlike the process of radioactive decay, which cannot be turned on and off, nuclear fission can be controlled.

The energy release caused by fission can be speeded up, slowed down, started or stopped. It can be used to destroy cities in the form of nuclear weapons, or to boil water inside a nuclear reactor (Edwards, 1992). Uranium atoms are radioactive and will disintegrate with time if they are left alone. However, if uranium atoms are neutrons – elementary particles without electric charge – much more violent disintegration of the atom takes place, which is called fission. When fission occurs, the uranium atom does not just disintegrate, it actually breaks apart into two or three large chunks (Edwards, 1992). In the process, it gives off some extra neutrons and about 400 times as much energy as is produced by a radioactive disintegration event.

Based on the facts about Uranium,
  1. Does Zambia, as a country, have the technical expertise to regulate and supervise the exploitation of the deadly metal – uranium?
  2. Do the socio-economic benefits accruing to the affected communities outweigh the health risks associated with this exploitation and mining activities?
  3. What roles do the rural communities that are directly affected by uranium exploitation and mining, play in the decision-making processes leading to commencement and operation of these activities?
  4. Did AER, DML and LMC do community programs to raise its awareness on the benefits and challenges arising from uranium mining and processing, and how they can safeguard themselves against any adverse health effects arising from these activities?

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