Can living near oil or natural gas fields affect drinking water?

​New York: Living near oil or natural gas fields may not necessarily affect your drinking water unless the well is poorly constructed or there are problems associated with hydraulic fracturing or fracking. “We have found a number of homes near active wells with very high levels of natural gas in the tap water," said Rob Jackson, professor of earth system science at Stanford University.

“Where the chemistry suggests contamination, the problem usually lies with the integrity of the well, either the cementing used to isolate it from the surrounding rock and water or the steel casing that allows gas and oil to flow upwards,” he explained. Most documented cases of groundwater contamination were caused by poorly constructed wells, he said.

Besides structural issues, Jackson and his colleagues have identified problems associated with hydraulic fracturing, or fracking. The technology uses pressurised sand, water and chemicals to crack open rocks and release trapped reservoirs of oil and gas. Fracking wells are often installed a mile or more below the surface, far from underground sources of drinking water.