The Nuclear Waste Management Organization has started drilling test boreholes in South Bruce, an important step to determining if the location is suitable to store used nuclear fuel underground.
The first of two boreholes was started northwest of Teeswater in recent weeks and has reached a depth of about 20 metres as the NWMO evaluates the potential of the site as a deep geological repository.
“It is kind of a crucial step for us and for the project,” said Martin Sykes, senior geoscientist with the NWMO. “It is that next step, from understanding what is on the surface to understanding what is at depth.”
The drilling of the borehole from ground level to about 900 metres underground will take about three to four months, followed by three or four months of testing. The whole process is expected to last about nine months. A second borehole, further west along Concession Road 8, northwest of Teeswater, is scheduled to begin in September and will also take about nine months.
“This is where we get a lot of our data around the actual safety and suitability of the site so the borehole drilling has really been a big milestone in the project,” he said.
South Bruce is one of two locations being proposed for NWMO’s proposed deep geological repository.
The other location is in the Township of Ignace in northern Ontario, where borehole drilling began in 2017.
The NWMO has secured approximately 1,500 acres of land at each location and anticipates selecting a single preferred site in 2023. They are the last remaining sites of 22 where officials expressed an interest in being home to the DGR when the process began more than a decade ago.
The ultimate aim of the DGR project to create a long-term storage solution for spent fuel rods currently stored above ground at nuclear sites.
The proposal would include a $23 billion buried storage vault for used fuel rods and a testing centre for technologies needed for the project.
The project requires 250 acres for facilities on the surface, with the estimated footprint of the underground storage area about two kilometres by three kilometres (1,480 acres), depending on a number of factors, such as rock characteristics and features and the amount of used fuel to be stored.
That storage area would be located about 500 metres below the surface depending on the rock characteristics of the site.
The NWMO timeline of the project anticipates the regulatory approval process to take about a decade, followed by construction beginning in 2033 and taking 10 more years, with operation starting in 2043.
The formation being targeted as potential for the repository in South Bruce is known as the Cobourg Formation, a limestone formation expected to be about 670 metres deep, Sykes explained.
The rocks in the area are around 450 million years old. The formation is made up of argillaceous limestone, a rock that is very strong, has very little or no ground water in it and has shown to be consistent over a large area, Sykes explained.
“You can see it in boreholes in the area at 670 metres depth and you can also see it in quarries in Bowmanville where it has similar properties where it is actually at the surface,” Sykes said. “Our work here is to build on our understanding of this formation and confirm some of the characteristics.”
The borehole drilling will help the NWMO understand the geology above, below and at the depth of the potential repository site, so they have a good understanding of the local geology, including rock type and groundwater in the area.
The borehole drilling also ties into all the other fieldwork studies being conducted in South Bruce required to put together the data needed to understand the geology, safety and suitability of the location, Sykes explained.
Last month the NWMO announced it had begun an expanded water well sampling program in South Bruce, a first step in implementing its environmental baseline monitoring program co-designed with the municipality.
The program is to provide residents with assurance that their water will be safeguarded and will help landowners and the NWMO better understand water resources and quality in the area around the potential repository site, according to NWMO.
Sykes said other studies are also planned, including seismic studies.
NWMO already has a good regional understanding of the geology, as the area has had a lot of boreholes drilled for other industries and that data can be integrated into their model for the site, Sykes said.
“It gives us a good idea of where we expect to see the different formations and the different geology at depth,” said Sykes. “We have a good basic understanding of the regional geology and this project is going to help us understand the local geology of that site.”
Sykes said that along with their community engagement work, the technical work being done is a key part of the project, and the borehole work is an exciting step for NWMO.
Meanwhile, as the technical work continues, earlier this month the Municipality of South Bruce launched the process of consulting the community to determine its willingness to play host to the DGR.
The municipality has hired a consulting firm – GDH Limited – to determine how they would like that willingness to be measured. The NWMO is also developing a willingness criteria, but South Bruce and Saugeen Ojibway Nation are working independently to each decide how they will determine community willingness.
The project has had opposition in the community, with the Protect Our Waterways – No Nuclear Waste organization speaking out against the project, distributing signs and gathering thousands of signatures. A separate group, South Bruce DGR – Willing to Listen, is said to be made up of people who are neither for or against the project, but are “committed to learning more” about the proposal.
Beginning next month, South Bruce plans to provide opportunities for the public to express how they want their willingness measured, including virtual workshops, an online survey, monthly drop-in Zoom calls and one-on-one discussions with GHD consultants.
The municipality plans to mail out information to residents this month on how to participate in the process. It will also regularly update information at southbruceswitchboard.ca/
A report is expected back to the community in the fall to validate the information collected, with a report by GHD going to South Bruce council in November.