The natural gas used to cook our food and/or heat and cool our homes is 90 percent clean-burning methane, the simplest form of hydrocarbon. But that's not the case for natural gas as it comes out of the ground. Depending on the location of the well and the geologic conditions that created the gas in the first place, contaminants such as water, sulfur and natural gas liquids (including ethane, propane and butane) may be present. So-called “gathering pipelines” collect natural gas from wells in a given region and deliver it to local processing plants. The processed gas then enters the interstate pipeline distribution system.»next
Special thanks to the Interstate Natural Gas Association of America (INGAA) and the Natural Gas Supply Association (NGSA) for helpful technical advice and assistance with this segment.