contractor did not estimate properly? correct. how much water was behind that mine. correct. he shut down an old mine, ground water from underneath building up in that mine. they did not properly estimate how much water had backed up in there at huge pressure. so when they began moving the rock, dealing with what was capping it, trying to get a pipe in there to get that water out, it blew out like a volcano, 3 million gallons of this horrible stuff. and what is in this horrible stuff and what is the damage to fish, to other wildlife, and to humans being able to swim, boat, raft? this water contains heavy metals. that s the real problem. we re talking about lead, arsenic, possibly copper. this is what you would expect in that water. and these heavy metals don t deteriorate in the water. they flow downstream. depending on the stream rate flow, they will settle in. they get into the sediment. they can be fed by bottom