Adelphia Gateway is a plan to convert an old/existing 84-mile oil pipeline stretching from Northampton County, PA through Bucks, Montgomery, and Chester counties, terminating in Delaware County at Marcus Hook, into a natural gas pipeline–flowing Marcellus gas to southeast PA. Roughly half of the pipeline was previously converted and already flows natgas. In December the Federal Energy Regulatory Commission issued final approval for the project (see FERC Issues Final OK for Southeast PA Adelphia Gateway Pipeline). In March 2019 Adelphia filed a request with the PA Dept. of Environmental Protection for a federal Clean Water Act 401 permit to cross streams and wetlands. The DEP finally issued the 401 permit this past week.