Saturday, October 17, 2009

shale and our water

NYTimes | New York State’s environmental regulators have proposed rules to govern drilling in the Marcellus Shale — a subterranean layer of rock curving northward from West Virginia through Ohio and Pennsylvania to New York’s southern tier. The shale contains enormous deposits of natural gas that could add to the region’s energy supplies and lift New York’s upstate economy. If done carefully — and in carefully selected places — drilling should cause minimal environmental harm.

But regulators must amend the rules to bar drilling in the New York City watershed: a million acres of forests and farmlands whose streams supply the reservoirs that send drinking water to eight million people. Accidental leaks could threaten public health and require a filtration system the city can ill afford.

Natural gas is vital to the nation’s energy needs and can be an important bridge between dirty coal and renewable alternatives. The process of extracting it, however, is not risk-free. Known as hydraulic fracturing, it involves shooting a mix of water, sand and chemicals — many of them highly toxic — into the ground at very high pressure to break down the rock formations and free the gas.

The technique is used in 90 percent of the oil and gas operations in the United States. And while most drilling occurs without incident, “fracking” has been implicated in hundreds of cases of impaired or polluted drinking water supplies in states from Alabama to Wyoming.

The dangers are particularly acute in the Marcellus Shale, which, unlike the relatively shallow formations found elsewhere, lies miles underground. Getting the gas out will require far more water and heavy doses of chemicals. While the rules would require drillers to take special precautions in the watershed, there are too many points — from the delivery of the fluid to the drilling site to the removal of spent fluid after it surfaces — where poisoned water could escape into the water supplies.

Quarantining the watershed also makes economic sense. The shale contains only one-tenth of the gas in the southern tier. One big accident could undo everything the city and state have done — buying up property, creating buffer zones around the reservoirs — to protect the watershed from development and pollution.

The hazards to fresh water posed by massive fracking are fairly well understood. Do we really have the luxury of poisoning this much of our freshwater supply in the name of natural gas development? The question needs to be asked again: What do we value more, energy to run our machines or water to sustain human life?