Fossil fuels
are rich in hydrocarbons, which are naturally occurring compounds. Coal and oil are two fossil fuels that powered the Industrial Revolution and continue to be widely used today. They are energy-rich hydrocarbon fuels that are generally considered to be nonrenewable, forming over long periods of geologic time. They cannot be expected to regenerate in a human lifetime.
The advantage of coal and oil is that they occur in high density, concentrated sources. Obtaining and using the fuels, however, is fraught with opportunities for pollution. Hydrocarbon pollution is multifaceted. One example is oil drilling and extraction. There is the initial site disturbance, whether at sea or on land, of establishing a facility to begin to pump the oil out. This disturbance in itself is a form of pollution in the broadest sense. Once oil extraction begins, accidental spills are inevitable. Whether on land or sea, crude oil is a harsh pollutant.
Coal has its own pollution problems. Techniques for extracting coal from the ground include mountaintop removal. This is a destructive process that radically alters the landscape and results in toxic runoff from impurities, such as selenium, that are a byproduct of coal removal.
Again, concerning oil, the risks of pollution are ever-present, not only during the extraction process but during transport. The most infamous example is that of the Exxon Valdez, the oil tanker that spilled millions of gallons of oil in Prince William Sound in Alaska in 1989.
Oil is transported to refineries where various chemical processes are conducted to transform it into more usable forms. A refinery facility itself occupies a sizable swath of land and has a decided effect. The refining process has both on-the-ground and atmospheric emissions and effects that qualify as pollution. Once the oil is refined into various products, such as diesel fuel, home heating oil and gasoline, there is additional transport and potential for spilling. These events can and do occur. Oil trucks and rail-based tanker cars are involved in accidents where fuel is spilled, running onto the ground and into waterways.
Once the fuels---whether derived from oil or coal---arrive at their final points of use, the pollution stream continues. Burning coal, heating oil, diesel fuel and gasoline results in an array of compounds that pollute the air. Although not an especially toxic compound, carbon dioxide is a high-profile example of one pollutant. Being the potent greenhouse gas that it is, carbon dioxide is widely implicated in global climate change. Other compounds, such as sulfates and nitrates that result from burning fossil fuels, cause air and water pollution.
Finally, disposal of products manufactured from oil---including plastics---represents yet another part of the waste stream.
Tags: carbon dioxide, diesel fuel, fossil fuels, fuels that
