I'm 55 years old, and I remember how polluted it used to be. When I was a kid, Lake Erie was dead. The river near our house (near Verona, PA) was full of trash and industrial waste.
Most every family on our road would burn their trash in the creek to get rid of it. The creek was foamy with runoff from the new housing up on the hills. Older homes flushed their toilets directly into the creek. Fishkills were common (Google "Bruin Lagoon"). Riverfront property did not have great value like it does today.
When my folks would take us to Pittsburgh for baseball games or to the museum, we would have to roll the car windows up. Dad would have to turn the headlights on in the middle of the day, because the smoke from the mills was so bad.
Whenever I hear that businesses want government to soften or rollback the hard won environmental policies we have now, I think to myself, "Have they forgotten how bad it can get?"
Perhaps most are just too young and have never experienced it, or maybe the well-to-do are just insulated from it. If you don't know about this stuff or don't believe me, take a moment to look up Bruin Lagoon, or Love Canal or read Rachel Carson's "Silent Spring." Never forget!