Singapore could manage its own nuclear waste without major technical hurdles if the nation adopts nuclear energy, according to a desktop study conducted by the Energy Market Authority (EMA) and SKB International. The findings suggest that deep geological repositories or deep boreholes may provide viable storage options for the small, densely populated country.
Why is nuclear waste management a priority for Singapore?
The EMA and the National Environment Agency (NEA) commissioned a study in 2023 to evaluate the implications of radioactive waste management for Singapore. This comes as the government mulls over nuclear power as a potential clean energy source.
Managing this waste is critical because radioactive by-products can remain hazardous for thousands of years. If not handled properly, these materials can cause serious damage to human health and the environment. For instance, high-level waste like used uranium fuel rods contains particles such as plutonium-239, which takes approximately 240,000 years to decay to lower levels.
The International Atomic Energy Agency (IAEA) is set to evaluate Singapore’s capabilities in managing radioactive waste in 2027. This will be one of 19 critical areas assessed by the UN nuclear watchdog to help the nation make an informed decision on nuclear energy deployment.
How much waste would a nuclear reactor produce?
The volume of waste generated depends on the type of reactor used. A traditional 1GW large reactor can produce about 370,000 litres of nuclear waste annually, which would fill roughly one-seventh of an Olympic-sized swimming pool. Of that amount, about 5 per cent is considered high-level waste.
In comparison, Singapore’s Semakau Landfill has a capacity of more than 11,000 Olympic-sized swimming pools. The study also noted that existing waste management approaches are feasible for small modular reactors (SMRs), which have a power capacity of up to 300MW.
What are the proposed storage solutions?
One option involves deep geological repositories, which are man-made networks of underground tunnels designed to isolate radiation from living things for hundreds of thousands of years. These facilities typically use multiple layers of defense, including corrosion-resistant copper canisters and buffer clay that swells to close rock fissures.
Mark Lim, chairman of the Institute of Electrical and Electronics Engineers Nuclear and Plasma Sciences Society’s Singapore chapter, noted that Singapore’s granitic formations, such as the Bukit Timah granite and rocks on Pulau Ubin, may be suitable. However, for successful geological isolation, the granite must be unfractured and free of fault lines to prevent groundwater from transporting particles.
Given Singapore’s land constraints, Lim suggested that the country could also consider drilling deep boreholes. This emerging method involves placing fuel canisters at the bottom of a 5km-deep hole, far below shallower groundwater aquifers, and sealing them with bentonite clay, cement, and asphalt.
What challenges remain for Singapore?
While the desktop study found no technical “showstoppers,” the EMA noted that additional surveys on the country’s geophysical environment are still required. Future studies will need to scrutinize rock samples, monitor groundwater movement, and assess environmental impacts.
Social perception remains a significant hurdle. Matthew Chew, nuclear competency and strategy lead at engineering consultancy HY, pointed out that public engagement will be essential. He noted that in Finland, it took nearly 20 years to select a site and another 20 years before operations could begin at the Onkalo site.
Frequently Asked Questions
What is the difference between low-level and high-level nuclear waste?
Low-level waste includes items like contaminated gloves and uniforms, while high-level waste refers mainly to highly radioactive used uranium fuel rods.
Is the current study’s finding final?
No. The findings were based on a desktop study that did not include on-site investigations. Future surveys will be needed to make a comprehensive assessment.
When will the IAEA assess Singapore’s nuclear readiness?
The Republic is scheduled to undergo an assessment by the UN nuclear watchdog in 2027.
How do you feel about the prospect of nuclear energy being part of Singapore’s future?
