CPACT Webinar on
Using a combined LIBS and Raman
spectroscopic approach to monitor spent nuclear fuel in a dry storage cask
environment
Rebecca
Clews1,
Louise Natrajan1, Dirk Engelbert1, Sean Woodall2
1 University of Manchester, 2 United
Kingdom National Nuclear Laboratory
21st
May 2026 at 3pm (UK time)
As part
of the Nuclear Decommissioning Authority’s (NDA) strategy outlined in 2021, the
majority of the UK’s spent nuclear fuel (SNF) inventory is set to be stored in
interim spent fuel containers pending its final disposal. There are two methods
in current operation for the storage – wet and dry. Dry storage has already
been widely deployed globally, in countries such as the USA, Canada, Belgium,
and Germany [1]. Although some sites in the UK such as Wylfa [2] and Sizewell B
[3], with Hinkley Point C following suit [4], have implemented dry storage for
their SNF, the most established technique in the UK, and globally, remains wet
storage [5]. However, wet storage has limitations for certain fuel types, and
so dry storage is being considered as a more versatile alternative.
Currently, there are no mature
monitoring techniques in the UK for the interim dry storage of SNF. This
project hopes to bridge this gap in knowledge by developing a combined LIBS
(Laser-Induced Breakdown Spectroscopy) and Raman spectroscopy approach to monitoring
the SNF. The two techniques would be deployed in-situ, with stand-off detection
of the key chemical species involved in the degradation of the fuel. By using a
combined approach, a full chemical analysis of any potential species present
can be performed.
During testing of the two
methods, several species of interest will be measured using the techniques.
LIBS will be used to determine the LOD of Xe and Kr in inert gas, which if
present during storage would indicate fuel cladding failure. Raman spectroscopy
will be used to determine the LOD of various polyatomic molecules:
·
H2/O2 – produced from the
radiolysis of water, the presence of these gases would indicate a penetration
of water into the container. This has concerns for pressurisation and localised
corrosion. The gases may also arise from inadequate drying of the fuel pre-disposal.
·
N2/air – these gases would only be
present if the cask integrity has been breached, allowing surrounding ambient
air to penetrate the container.
While
outside the scope of this project but forming the bulk of the motivation for
the work, the production and detection of H2 and O2 specifically,
during this storage, has significant implications for the formation of
oxidising impurities and pressurisation of the cask.
[1] El-Samrah,
M., Tawfic, A. F., Chidiac, S. Spent nuclear fuel interim dry storage; Design requirements, most common
methods, and evolution: A review. Annals
of Nuclear Energy. Vol 160. Sept 2021. doi.org/10.1016/j.anucene.2021.108408
[2] C.C.
Carter. 1995. Current and future applications of vault dry storage.
Proceedings of the International Conference on Fuel Management and Handling.
100-107. March 1995.
[3]
Sizewell
B. Office for Nuclear
Regulation. Available from: Sizewell
B | Office for Nuclear Regulation (onr.org.uk)
[4] Proposed change to how Hinkley Point C stores radioactive waste. Environment Agency. Gov.UK. July 2022. Available
from: Proposed
change to how Hinkley Point C stores radioactive waste - GOV.UK (www.gov.uk)
[5] Storage
and Disposal of Spent Fuel and High Level Radioactive Waste. IAEA.
Available from: Storage_and_Disposal_of_Spent_Fuel
(iaea.org)
This webinar will last no longer than one hour.
The webinar is for CPACT members only and is free to
attend.
Please register at https://universityofstrathclyde.webex.com/weblink/register/rfaa9873053181c267195100adf49edf0