The problem is we're not talking about small amounts of hazardous waste by-products whre you have a once a month pickup. We're talking about all of the ore that they process, potentially hundreds of thousands or millions of tons. Moving that anywhere else would be a huge and expensive undertaking, and negates any advantages of having the mill close to the mountain. Putting it all in buildings is equally problematic. They need to be able to dispose of it on site.