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The transportation of this waste poses an unacceptable risk to people and the environment.

Nuclear materials have been transported safely (virtually without incident and without harmful effect on anyone) since before the advent of nuclear power over 50 years ago. Transportations of nuclear materials cannot therefore be referred to as 'mobile Chernobylís'.

The primary assurance of safety in the transport of nuclear materials is the way in which they are packaged. Packages that store waste during transportation are designed to ensure shielding from radiation and containment of waste, even under the most extreme accident conditions. Since 1971, there have been more than 20,000 safe shipments of highly radioactive used fuel and high-level wastes (over 50,000 tonnes) over more than 30 million kilometers (about 19 million miles) with no property damage or personal injury, no breach of containment, and very low radiation dose to the personnel involved.

 

Plutonium is the most dangerous material in the world.

Plutonium has been stated to be 'the most toxic substance on earth' and so hazardous that 'a speck can kill'. Plutonium is indeed toxic and therefore must be handled in a responsible manner. Its hazard is principally associated with the ionizing radiation it emits. However, it is primarily hazardous if inhaled in small particles.

Comparisons between toxic substances are not straightforward since the effect of plutonium inhalation would be to increase the probability of a cancer in several years time, whilst most other toxins lead to immediate death. Best comparisons indicate that, gram for gram, toxins such as ricin and some snake venoms and cyanide are significantly more toxic. Consider also that all the cleaning products that we have in our kitchen are toxic if we absorb them, whilst some of the products that are spread onto crops are toxic as well.

 

There is a potential terrorist threat to the large volumes of radioactive wastes currently being stored and the risk that this waste could leak or be dispersed as a result of terrorist action.

High-level waste (HLW) and used fuel is kept in secure nuclear facilities with appropriate protection measures. Most high-level wastes produced are held as stable ceramic solids or in vitrified form (glass), designed to ensure that radioactive isotopes resulting from the nuclear reaction are retained securely in the glass or ceramic. Their structure is such that they would be very difficult to disperse by terrorist action, so that the threat from so-called 'dirty bombs' is not high.
The US Nuclear Regulatory Commission (NRC) has responded to suggestions that spent fuel is vulnerable to terrorist actions and should be put into dry storage casks after five years: "Nuclear power reactor spent fuel pools are neither easily reached nor easily breached. Instead, they are strong structures constructed of very thick steel-reinforced concrete walls with stainless steel liners. In addition, other design characteristics of these pools, not analyzed in the paper, can make them highly resistant to damage and can ease the ability to cope with any damage. Such characteristics can include having the fuel in the pool partially or completely below grade and having the pool shielded by other plant structures."



A report released on June 25, 2002 by the National Academy of Sciences, concludes that if a dirty bomb attack were to occur, "the casualty rate would likely be low, and contamination could be detected and removed from the environment, although such cleanup would probably be expensive and time consuming." The disruption caused by such an attack would result from public fear of anything 'nuclear', and thus "the ease of recovery...would depend to a great extent on how the attack was handled by first responders, political leaders, and the news media, all of which would help to shape public opinion and reactions."

The International Atomic Energy Agency (IAEA) has identified medical and industrial radioactive sources as posing considerable concern in terms of potential terrorist threats from their use in 'dirty bombs'. The need for stronger controls to prevent the theft or loss of control of powerful radiological sources and hence ensure their safety and security has been highlighted as of paramount importance.

 


Date: 2015-12-11; view: 645


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