The following study was found to show emissions from natural gas pipelines according to this article: Compressors on natural gas pipelines measured releasing high concentration plumes of gas
“The study was conducted by Bryce Payne and Bob Ackley, of Gas Safety,Inc., with A. Paige Wicker, Zacariah L. Hildenbrand, Doug D. Carlton Jr. and Kevin A. Schug, of the University of Texas at Arlington1. Measurements were made on public roads in the area of 9 compressors in Pennsylvania and New York. Compressors are needed about every 50 miles to push the gas along the pipelines, using turbines and usually pipeline gas driven motors; all those studied were gas driven.
The study reveals rogue methane a full mile from the compressor stations tested. Only methane was measured, but is a proxy for the mixture that is natural gas. While these plumes are composed predominantly of the greenhouse gas methane, which accounts for 80 to over 90% of natural gas, they also can contain nitrogen oxides, particulate matter, sulfur dioxide, radon and volatile organic compounds, among other materials.”