After nearly four decades of use, Saskatoon’s nuclear reactor is one step closer to being shut down.

The Saskatchewan Research Council (SRC) has defueled its Slow Poke nuclear reactor and safely moved the fuel to the United States.

The reactor has been vital in research to the mining industry. It’s been used by scientists and companies to complete about 240,000 tests.

The reactor is only one of seven in Canada.

The SRC has been in the process of shutting down Slow Poke since 2017 because it’s too costly to maintain and there’s more modern technology to get the same testing done.

It costs about $6 million to shut down the reactor.