Radioactive Sources - An Invisible Hazard

The 2011 earthquake and follow-on tsunami disaster in Fukushima, Japan, highlighted both the impact a radiological disaster can have on the local community and the inability of even the best emergency managers to effectively plan for such incidents. In order to properly plan and respond to disasters, emergency managers must be fully aware of where, specifically, radioactive materials can be found within their communities.

Among the primary sources of radioactive materials, and probably the best known by the general public, are nuclear power plants. Because these plants are often owned and operated by private power companies, they usually have their own emergency managers and plans. By closely coordinating with the company’s emergency management division, therefore, community and/or state emergency managers can learn what those managers know about radioactive hazards and the proper responses needed to cope with various hazards or other problems the power plant may experience. Nonetheless, as was demonstrated at Fukushima, an unexpected nuclear power incident can very quickly overcome the capabilities of local responders, and assistance from higher levels of government may be required.

An additional concern is that most nuclear waste is typically stored, at least temporarily, at or near the nuclear power plant producing the waste. As the plants are refueled, the spent fuel is stored in on-site facilities until it can be transported to a long-term storage facility. Most low-level waste also is stored on-site, which represents an additional hazard that must be taken into account during and after an on-site fire, flood, or other crippling disaster.

Although not necessarily widespread, smaller research and test reactors can be found at many local colleges and universities; very few of them, however, are even close to the size of the reactors in civilian power plants. For example, the reactors at the Calvert Cliffs Nuclear Power Plant in Lusby, Maryland, have a collective power capacity of approximately 870 megawatts; the capacities of smaller test reactors, though, typically fall within a range of less than one megawatt up to about 20 megawatts – but average approximately 1.8 megawatts. A major concern is that those responsible for the smaller reactors may not have the support of a designated response team – or even the plans needed to cope with an unexpected emergency situation. Therefore, emergency managers should be aware of the facility’s plans and response capabilities, and take them into consideration when devising their own disaster response plans for nearby communities.

Medical & Industrial Sources of Radiation

The most likely sources of radioactivity that would be encountered by responders and receivers in most local jurisdictions are the systems, devices, and equipment used in and by the medical community. Radioactive sources are used in a variety of procedures ranging from radiation therapy in the treatment of cancer and clogged blood vessels to diagnostic uses in imaging body parts or determining bone density. Radioactive sources can be found in a variety of medical facilities – the most likely being fully equipped hospitals, but many doctors’ offices also have in their equipment inventory relatively small imaging units and/or radiation therapy devices. In addition to hospitals and medical specialist offices, dental and veterinary clinics may house a few frequently ignored radioactive sources as well. Although the amount of radioactive material found in these machines is relatively small, there are still some risks associated with their use.

In modern nations, many industrial facilities – including shipyards and metal fabricators – have equipment and processes that use radioactive sources. Radiography machines, for example, are used (for the quality assurance of metalwork) to inspect welds and metal parts for defects. Irradiators, frequently used for X-rays and other medical/therapeutic purposes, have a number of other uses – for example, the sterilization of medical supplies, as well as the preservation of milk, fruits, and vegetables – but also expose the products to gamma radiation.

One specific concern regarding medical and industrial radioactive sources is their security. Although there have been no radioactive dispersal devices (otherwise known as dirty bombs) used against the United States, there have been numerous situations involving stolen radioactive material, including but not limited to the following: (a) two radioactive bomb threats reported in Russia, near Chechnya, in 1995 and 1998; (b) 19 small tubes of cesium stolen from the Moses Cone Memorial Hospital in Greensboro, North Carolina, in 1998; and (c) a former Russian KGB officer in London assassinated by radiation poisoning in 2006.

A significant example of how stolen radioactive material can be accidentally used occurred in Goiânia, Brazil, on 13 September 1987 when two scavengers entered an abandoned hospital and found a radiation therapy unit. Apparently thinking it would have some scrap value, they took it home and started to dismantle it. Eventually, they freed the radioactive source, but by that time they had already started to personally experience some symptoms of radiation poisoning (including vomiting, dizziness, and radiation burns on their skin). The unit was sold shortly thereafter and further dismantled, spreading the radioactive cesium dust among various friends and family members. Eventually, the incident was discovered – after four people had died and 249 others were significantly contaminated with radioactive particles. Even without any evil intent, there is still a significant danger when radioactive sources are not properly secured.

The Proper Disposal of Radioactive Waste

There are two major categories of radioactive waste: low-level and high-level. The most common is low-level waste – contaminated rags, for example, as well as a varying array of filters, injection needles, medical tubes, tools, and other medical or dental equipment items. The radioactivity of this waste can range from just above the background levels found in nature to higher levels of radioactivity in certain cases such as parts from inside nuclear reactor vessels. Low-level waste comprises 97 percent of the volume, but emits only 8 percent of the radioactivity, of all radioactive waste. Such waste is typically stored on site by the producers of that waste until it has either decayed – and can be disposed of as normal trash – or is shipped to a low-level waste disposal site.

The second category is high-level waste, which consists primarily of spent fuel from reactors. Some countries – for example, France, the United Kingdom, Russia, India, and the United States – reprocess varying quantities of spent fuel, but the processing itself creates additional types of high-level waste. The latter are typically stored at the site that produced them because there are at present (so far as is known) no national or regional repositories that can be safely used to store high-level waste.

This type of radioactive waste is then transported – by truck, rail, and sometimes by purpose-built ships using robust and secure containers – to various areas, fairly distant from highly populated communities, for storage and disposal. Containers made from layers of steel and lead have been used in more than 3,000 shipments of spent fuel with no apparent impact on the containers themselves from the radioactive contents. Low-level waste is transported in containers considered to be appropriate for the levels of radiation found in the waste. As with any other type of hazardous/dangerous material, the transport vehicles themselves are clearly labeled with the name of the hazardous material inside, a common-sense precaution that permits the quickentification of the material when an accident does occur.

Because of the continuing proliferation of radioactive materials throughout many modern nations, emergency responders must be prepared at all times for the possibility of encountering radioactivity – in fires and/or floods and many other types of disasters, both natural and manmade. By always knowing specifically where these materials are stored, emergency planners, responders, and receivers will be much better prepared to cope effectively with an invisible but nonetheless dangerous radioactive threat.

Stephen Jolly

Stephen Jolly has served more than 20 years as a nuclear operator and trainer in the Navy’s Nuclear Power program. He was the nuclear training program manager in his most recent post, the nuclear-powered aircraft carrier USS Dwight D. Eisenhower (CVN-69), where he was responsible for the continuous training of more than 350 Navy officers and enlisted personnel. He also serves as an instructor on the Anne Arundel County (Md.) Community Emergency Response Team (CERT).



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