Before becoming suitable for nuclear energy, producers extract uranium from the ground and process it into uranium ore concentrate. UOC must then be transported to a facility to be converted to uranium dioxide (UO2) or hexafluoride (UF6) gas. The transportation process is extensive, presenting a host of formidable yet manageable risks.
Uranium is extracted, processed into UOC–which contains uranium oxide, primarily ammonium diuranate (ADU) and U3O8 (often called yellowcake), but also uranyl peroxide (UO4). Uranium rock from an open cut mine is milled, and then processed into UOC. The uranium is then precipitated and finally filtered, dried and packaged into 200 litre drums (400kg/881lbs) or four-ton hoppers ready for transport by land and/or sea to a conversion facility. During conversion, UOC is chemically and/or physically altered into either uranium dioxide (UO2) or hexafluoride (UF6) gas. Sometimes an intermediate product is then further transformed into (UF6), which is the feedstock for centrifuges at a uranium enrichment plant.
A drum of concentrated uranium can travel long distances because commercial conversion facilities are located in only five countries – Canada, China, France, Russia, and the United States. The United Kingdom closed its Springfields conversion plant in August 2014, after sixty-eight years of operation. Of these nations, Canada is the only non-nuclear weapon state. The other five are officially recognized nuclear weapons states under the Nuclear Non-Proliferation Treaty (NPT). The majority of the world’s uranium therefore passes through one of these countries before it is further processed as fuel for a nuclear reactor. For example, a drum of yellowcake leaving a mill in Australia can travel 5,000km (approx. 3,106mi) to China, 15,000km (approx. 9,320mi) to Europe or upwards of 20,000km (approx. 12,427mi) to conversion facilities in Illinois, United States or Ontario, Canada.
It should be noted that Iran, Israel, North Korea and Pakistan also have conversion facilities – these however do not commercially process UOC from (or to) abroad. Until recently, India also stood outside of the global trade in natural uranium until its 2008 exemption from Nuclear Suppliers Group trade restrictions. As of December 2014, India has purchased and processed uranium from France, Russia, Kazakhstan and Uzbekistan for use in Indian civilian nuclear reactors.
The transport of shipping containers of UOC from mine site to conversion facility creates a potential vulnerability, given the significant distances travelled, the number of transfers of authority that a shipping container goes through, often across several borders, requiring multiple approvals in multiple jurisdictions. Such vulnerabilities are addressed by the IAEA through their safety and security standards and industry best practice.
Physical protection practices can be quite rigorous — as mine owners in conjunction with transporters and in some instances governments put in place specific measures to manage and mitigate risk. Precautions often include designated routes requiring designated rest stops, requirements for additional drivers, and GPS tracking on trucks to monitor location and driving behavior. The fitting of container bolt seals to shipping containers or dry van trailers assists in detecting any tampering with cargo containers during intermediate or long term storage, a technique used for many high value cargoes.
A container carries around 20-35 drums, or approximately 10 tonnes of uranium, which is considered a “significant quantity,” i.e. the quantity for which the possibility of manufacturing a nuclear explosive device cannot be excluded. The “significant quantity” is the standard agreed to by the international community as the basis for IAEA safeguards.
Diversion or theft of a single cargo container of UOC is a valid concern from an international safeguards perspective. The IAEA has determined that the timeline for detection of a significant quantity of uranium is one year. However, industry and regulators have expressed that detecting unauthorized removal of a single drum over a one-month period is prudent.
As of mid-2014, no accident beyond level 1 on the International Nuclear Event Scale (INES) has ever been reported for nuclear material transportation. Of the 20 million transports of radioactive material that take place in the world each year, 95 percent are not fuel-cycle related. In the case of the remaining 5 percent, spent fuel transports are by far the most hazardous. Even if less than 1 percent of this material is made of uranium235(U235), which means it is a “low-activity material,” UOC transportation follows the international rules related to nuclear material transportation with respect to both containment and control. These measures should be continuously evaluated against threats to ensure a graded approach when suppliers are experiencing heightened security environments and the risk of sabotage and unauthorized acquisition requires increased protection, inspection and enforcement.
2010 UOC spill during Altona’s journey from Canada to China
Transportation is a lengthy and risky process, in large part because UOC has to pass through only five conversion facilities worldwide–Canada, China, France, Russia, and the United States. Existing conversion facilities face economic and efficiency challenges. Currently, countries are aiming or attempting to optimize conversion rates and cut costs as existing conversion facilities are aging.
For example, until recently three uranium conversion facilities in Russia had an annual output capacity of 25,000 tons, yet only 35-55 percent of that capacity was actually in use. The equivalent figure for large uranium conversion facilities in other countries is in the range of 70-85 percent.
As part of its optimization and cost cutting program, Rosatom state nuclear energy corporation has decided to concentrate all its UF6 production at a single facility. The new conversion facility will use natural as well as reprocessed uranium (RepU). Its projected output is 18,000 tU/year for natural uranium, and 2,000 tU/year for RepU and the launch of the new facility at SKhK is expected to slash Russian costs by 50 percent from $10 USD/kgU in 2014 to $5 USD/kgU.
Uranium consumption varies around the world. Some countries, such as Brazil
, produce uranium, export it for conversion, and then transport it back to their home country to be consumed, while others such as Australia, Namibia, and Kazakhstan export all the uranium they produce. Canada consumes approximately 15 percent of its own production, fueling 20 CANDU reactors at three separate locations in Ontario and one in New Brunswick. The rest, nearly 85 percent of Canada’s total uranium production is exported.
Secure transport of “yellowcake” is just one area of concern as uranium flows around the globe. Another is the path from “ore to bomb.”