Coal pollution mitigation to encourage the introduction of coal pollution mitigation and other technologies to reduce environmental impact. Combustion of coal--which is mostly carbon--produces carbon dioxide as a product of combustion. According to the United Nations Intergovernmental Panel on Climate Change, the burning of coal, a fossil fuel, is a significant contributor to global warming. (See the UN IPCC Fourth Assessment Report). For 1 ton of coal burned, 2.86 tons of carbon dioxide is created. Carbon sequestration technology has yet to be tested on a large scale and may not be safe or successful. Sequestered CO may eventually leak up through the ground,
Carbon capture and storage (timeline) Sleipner field produces natural gas and light oil from the Heimdal sandstones, which are about 2,500 m below sea level. The natural gas produced at Sleipner contains unusually high levels (about 9%) of carbon dioxide, but the customers require less than 2.5%. To encourage companies to cut their carbon emissions, the Norwegian government imposes a carbon tax equivalent to about $50 per ton of CO released into the atmosphere. To avoid paying the tax, and as a test of alternative technology, all of the CO extracted since 1996, when gas production started at Sleipner, has been pumped back deep underground.