Nuclear power would be great, and extremely efficient, but environmentalists protest that the byproduct--usually depleted Uranium pellets, I believe--still gives off radiation and will therefore destroy the entire planet. However, these pellets, upon having outlived their usefulness, are collected into tubes/rods that are designed not to let any radiation or toxins in or out. Those tubes are set into barrels, which are designed not to let radiation or toxins in or out. Finally, these barrels are buried VERY far underground--much farther undergound than the water table--in, you guessed it, a hole dug, walled, coated, and filled in ways that don't let any radiation or toxins in or out.