The question is not about about "safely", the question is about "in a safer way than the alternatives". So, let's look at how we can safely store coal/oil wast

The question is not about about "safely", the question is about "in a safer way than the alternatives". So, let's look at how we can safely store coal/oil waste. We can't, it goes straight in the air, or in the sea. So in this sense, I'd argue even simply dumping our nuclear waste in the Mariana Trench would be safer.