Hydraulic fracturing, or "fracking," has gained popularity over recent years, and given the controversy over this practice, new research decided to lay out some of its environmental pros as well as cons.

Fracking involves blasting huge amounts of water, sand and chemicals deep into underground rock formations to access valuable oil and natural gas. While this is a form of alternative energy, it also has harmful environmental implications, influencing local air pollution, earthquakes and, especially, clean water supply.

A group of environmental scientists from Stanford University set out to answer some common questions about fracking.

"Society is certain to extract more gas and oil due to fracking," Stanford environmental scientist Robert Jackson, who led the new study, said in a statement. "The key is to reduce the environmental costs as much as possible, while making the most of the environmental benefits."

Fracking's hefty consumption of water is especially concerning considering that much of the United States is currently suffering from drought. Fracking requires more water than conventional gas drilling; but when natural gas is used in place of coal or nuclear fuel to generate electricity, it ends up saving water.

The impact of hydraulic fracturing on both climate change and local air pollution is similar to its impact on water, according to the study, published in the journal Annual Review of Environment and Resources.

Those living near fractured wells are potentially at risk of health threats given the increased amount of volatile organic compounds and air toxins in the area. On the flip side, when natural gas replaces, say coal as a fuel for generating electricity, the benefits to air quality include lower carbon dioxide emissions than coal and almost none of the mercury, sulfur dioxide or ash.

In terms of global climate change, however, scientists are still unsure of what role fracking's resulting toxins play in the greenhouse gas effect.

"While the increased gas supply reduces air pollution in US cities downwind from coal-fired power plants, we still don't know whether methane losses from well pads and pipelines outweigh the lower carbon dioxide emissions," Jackson explained.

But possibly the most cited issue associated with fracking is its impact on groundwater contamination.

"Wastewater disposal is one of the biggest issues associated with fracking," added co-author Avner Vengosh of Duke University.

Previous research has shown that 10 to 40 percent of the chemical mixture injected into the ground during fracking flows back to the surface during well development, Nature World News recently reported.

Although further research is needed to conclusively determine fracking's role in groundwater contamination, as well as climate change and air pollution, scientists behind this new study highlight several policies and practices that could optimize fracking's environmental cost-benefit balance.