By Bridget Carter, IAEA Department of Technical Cooperation and Gerald Nieder-Westermann, IAEA Department of Nuclear Energy

China has begun constructing its first underground research laboratory in the Gobi Desert, to determine the area’s suitability for future geological disposal of high level radioactive waste (HLW), including spent nuclear fuel, generated in China’s 51 operational nuclear power plants. Its construction follows more than three decades of research with the support of the IAEA. Scientists will use the laboratory to characterize and assess the geological, hydrological, geochemical and engineering characteristics of the rocks at the site.

China has been working on identifying a suitable site for a HLW repository since 1985, and since 1999 those efforts have been supported by the IAEA. “The safe disposal of high level radioactive waste is one of the critical missions for the sustainable development of China’s nuclear industry,” said Liang Chen, Vice President of the Beijing Research Institute of Uranium Geology (BRIUG), which is constructing the underground research laboratory.

The country’s strategy for HLW disposal consists of three stages, with stage one – laboratory studies and preliminary site selection – completed in 2020. The second stage, underground in-situ testing, is set to take place from 2021 to 2050, following the construction of the underground research laboratory. The final stage – the construction of the disposal facility – is planned to take place from 2041 to 2050, assuming the in-situ testing confirms the area’s suitability.

High-level radioactive waste can remain radioactive from thousands to hundreds of thousands of years. The internationally accepted solution for its safe and secure long term management is geological disposal in a facility several hundred metres underground. A geological disposal facility is under construction in Finland.

As part of the support from the IAEA, under the technical cooperation programme, 35 Chinese and 11 international experts took part in a six-week virtual expert mission earlier this year to provide input, guidance and recommendations to support plans for the in-situ laboratory.

“The construction of an underground research laboratory is an opportunity for advancement in the science and engineering of geological disposal facilities and an essential component in a sustainable energy future for countries,” said Head of the Disposal Team at the IAEA, Stefan Joerg Mayer. “Despite the constraints of the pandemic, we were able to design, organize and lead an innovative virtual mission to provide expert assistance to China in the construction of this new R&D facility.”

The virtual mission took place from 25 February to 9 April. In a series of 14 online, interactive meetings, the experts reviewed and assessed the plans for the construction of the underground research laboratory. They also reviewed the preparations being made for the development of a safety case for the disposal facility as well as for stakeholder engagement.

“BRUIG requested the IAEA to provide support on characterisation of the rock mass, as well as scientific research, prior to the construction of the URL.,” said  IAEA Programme Management Officer, Petra Salame. “Through this innovative way of organizing the expert mission, we were able to bring together a team of senior experts who addressed a broad range of topics that were proposed by our Chinese counterparts.”

“We discussed in-depth the interdependencies between the different thematic topics, from repository designs to radioactive waste management and their corresponding requirements on the properties of the site currently investigated,” said an international expert from Switzerland participating in the review, Piet Zuidema.

The broad range of areas covered resulted in recommendations related to construction, but also guidance related to the implementation of its laboratory R&D plans during the construction phase.

“This virtual Expert Mission was very timely as construction of the underground laboratory began this summer and it provided critical support to this effort,” said Chen. “It has made a great contribution in promoting the sustainable development of China’s nuclear industry.”