Sounds like a case of "it's too expensive to deal with this wastewater, so let's just put it in a big pond and hope the dam bursts and we can claim it was all a big accident" Mining industries are especially famous for this - there are ponds of waste that are 70 years old, just waiting for their moment to escape...
There's not much that can be done with it because essentially (not basically) it is acid. Phosphate mining uses sulfuric acid to extract the phosphates. These are large scale operations and produce a lot of water with a pH of 1.5-2. There's no comparable industrial process that can consume it as input. So it sits. The gypsum stacks are the other waste byproduct. But it's less problematic because it doesn't flow, it j…
Haha, I see what you did there...lol. Touche, good sir.