It hasn't counted when it's "accidental" - eg: pretty much all of the US uranium leach well mining resulted in tainted water in a "yeah we know, but don't care" process.

Also radioactive tailings dam collapses and hard rock mining consequences:

On Poisoned Ground

  The largest accidental release of radioactivity in the United States did not occur in 1979 at Three-Mile Island. That very same year a collapsing dam released a flood of radioactive debris into the Navajo Nation.

'We didn't know we were poisoning ourselves': the deadly legacy of the US uranium boom

  Tsosie was one of thousands of Navajos who took jobs in the mines, starting in the 1940s. They worked without masks or ventilation to disperse the lethal radon gas, and they were never told the rocks they were handling – leetso in the Diné language, or yellow dirt – were deadly.