The author purpose is to say Mining companies release pollute water that contained toxic and poisonous chemical into neutral been closed but no one know who to blame or how it happen .They no exact way to say who is the bad person because there are a lot of way for water to release down to creek river the how I know the author purpose is
that the author try to explain the way that water could come out and the possibility of each companies to be release the water since they blame each other because the topic it said that "Big Tunnel Funnelled Poisons Into Water and"Mine Owners Blame Each Other, EPA" another reason is in the text the author focus on who did it not what happen because in the text it mostly about the mining companies when it closed? How it happen?What dose worker say?.Lastly if you notice that only the first paragraph say something about what happen which is only one sentence but still in is came back to what I say in the start Mining companies release pollute water that contained toxic and "poisonous chemical into neutral" but all other part is connected to what I said in the beginning no one know who to blame or how it happen? In conclusion the author purpose is to say does this thing happen and who did it ?