The Nuclear Waste Management Organization has resumed drilling in the Ignace area, with work continuing on the fourth borehole.
The drilling, coring and testing is the next step in the search for a suitable site for an underground repository.
Work is also underway to set up the area in preparation for initiating drilling on the fifth borehole.
Director of Geoscience Sarah Hirschorn says this is one of the important ways to collect information about the geology and underground setting and allows them to learn more about the rock and water deep below ground.
The NWMO has also started to drill the first borehole at the second potential site in the South Bruce area.
Field activities can take up to nine months per borehole.