What is an ‘impaired’ waterway and why are there so many of them in Pennsylvania?

Link: https://www.pennlive.com/news/2019/04/what-is-an-impaired-waterway-and-why-are-there-so-many-of-them-in-pennsylvania.html?utm_source=CDRW+Members&utm_campaign=3f477f905c-EMAIL_CAMPAIGN_2017_08_04_COPY_01&utm_medium=email&utm_term=0_6209edbbbc-3f477f905c-5

Workgroup: Abandoned Mine Drainage, Agriculture, Pathogens and Point Source, Stormwater