Yeah anything that's flushed through dirty industrial cooling pumps is going to pick up lubricants, dust, pesticide, microplastics from parts rubbing against each other, basically all the industrial stuff that works it's way into the system which will get worse with age, and they'll have to put nasty chemicals in it to keep slime from growing.

Basically it's not drinkable and you wouldn't want to shower in it and nothing except slime can live it until its diluted enough.

Will they clean it before dumping it back into the environment every time they flush the system? The answer is no. They won't.

And the idea that it won't use that much water because they'll "recycle" it in a closed system is also bullshit. They will have to flush it all the time because water that's kept like that will foul no matter what you to do it and it will start to clog filters and cause issues. So yeah lots and lots of clean water in and lots and lots of nasty water coming out.

Oh yeah, and when the dumped dirty water evaporates, all the contaminates are left on the ground and will start to concentrate until it starts to be a bigger and bigger problem. It will get blown around into people's yards and crops and into food, pets, etc.