In February of 2017, Mountain Watershed Association (MWA), Clean Air Council (CAC) and the Delaware Riverkeeper Network (DRN) filed a legal appeal of the Mariner East 2 permits issued by the Department of Environmental Protection (DEP). After over a year of litigation the case was settled in early August 2018. This article details the outcomes and significance of the settlement that was achieved between the environmental groups and the DEP.