Lately there has been a lot of controversy about natural gas and the hydraulic fracturing (“fracking”) needed to extract it. So, when someone in my grad program brought up the dangers of fracking in class, I decided to do a little digging.
First, why the big fuss over natural gas? Natural gas is considered a fossil fuel because it’s formed when organic material beneath the Earth’s surface (like plants and animal remains) are exposed to heat and pressure over thousands of years. It is categorized as a non-renewable fuel source because it cannot regenerate on a human time scale. What’s got people excited is the fact that natural gas is cleaner burning than oil and coal. Research indicates that burning natural gas emits half as much carbon dioxide as coal and about 70% as much carbon dioxide as oil. Burning natural gas also emits lower amounts of nitrous oxides, sulfur dioxide, particulates, and mercury than coal or oil.
Cleaner burning sounds great. So, what’s the problem? The real concern lies with how natural gas is extracted. According to the Natural Resources Defense Council (NRDC), most natural gas is extracted from the Earth through a process called hydraulic fracturing, or “fracking.” Essentially, gas companies inject large amounts of water, sand, and chemicals into the ground at high pressures via concrete-lined wells. The high pressure causes the rock formation containing the gas to fracture, thus releasing the gas and sending it up the well.
The primary concern with fracking is that it can (and often does) result in water contamination. The chemicals injected can leach into the ground water supply. Research shows that the cement casings around the well pipes are compromised by the activity; 6% begin to leach material immediately, and 50% are leaching chemicals after 30 years. Those weaknesses pose a tremendous risk that hazardous chemicals end up in ground water and, ultimately, the drinking water supply. See The Sky is Pink documentary (a powerful 18 minute documentary exposing the natural gas industry) and the EPA for more details.
Additionally: 1) fracking puts a strain on the supply of surface and ground water because such large quantities are used in the fracking process, and 2) fracking releases volatile organic compounds (VOCs), hazardous pollutants, and greenhouse gases into the air. Some scientists have also postulated that fracking has led to an increase in small earthquakes within the U.S.
When it comes down to it, I don’t think anyone considers natural gas the clean fuel of the future, but many are thinking it will serve as a good stepping-stone between fossil fuels and clean, alternative energy. I don’t agree. In order to achieve these reduced emissions, we are compromising public health by allowing harmful chemicals to contaminate drinking water. I don’t think that is a sacrifice any of us would voluntarily make. If natural gas extraction is going to continue, we need to find a much safer way to proceed.