in 2014, waste management of pennsylvania, inc. was issued an erosion and sediment control permit for which the receiving waterbody is derr run. in 2007, the us gypsum company was issued a permit to build, maintain, and operate a long natural gas pipeline crossing the stream in two places, as well as crossing other streams. however, one of the crossings of derr run was planned to involve no impact to the stream; the other was planned to impact .