Pollution is the introduction into the environment a substance that has harmful or poisonous effects. Some pollutants, like uranium, last essentially forever.
The old saying that “an ounce of prevention is worth a pound of cure,” that it is easier to stop something from happening in the first place than to repair the damage after it has happened. This is certainly true when dealing with pollution.
Prevention is the only way to deal with the issue of uranium mining, milling, and waste.