Stanford Geophysicist Sets the Record Straight on Safety of Hydraulic Fracturing

Dr. Mark Zoback is a Stanford geophysicist and one of the world’s leading authorities on in situ stress, fault mechanics, and reservoir geomechanics with an emphasis on shale gas, tight gas and tight oil production. He was also a member of the National Academy of Engineering’s Deepwater Horizon investigation.

This week, the Los Angeles Times featured a Q&A with Dr, Zoback discussing issues ranging from his stance on regulatory issues surrounding resource development, drilling moratoria to the recent flurry of allegations connecting hydraulic fracturing and seismic activity. Here are some of his responses:

LAT: Do we know enough about fracking to draw up good regulations in the first place?
Zoback: “Absolutely. More than 100,000 horizontal and multi-stage “fractured” wells have been drilled in the U.S. and Canada. We know exactly what to do. It’s just a matter of making sure industry follows best practices, that we have good regulations in place, and those regulations are enforced.”

Sound familiar? America’s top regulators agree. Environmental Protection Agency Administrator Gina McCarthy echoes Zoback’s comments, “There’s nothing inherently dangerous in fracking that sound engineering practices can’t accomplish.”

LAT: California is considering a moratorium on fracking.
Zoback: “That’s very daunting, and moratoria just say this is bad, let’s stop doing it. Moratoria tend to make a political statement, but I’m not sure we need political statements. We need good science, good engineering, good regulations and good enforcement.”

Zoback’s statement here is one that many opponents of shale development simply can’t wrap their collective head around. The simple truth is this: the U.S. Energy Information Administration (EIA) forecasts that in 2040, eighty percent of U.S. energy consumption will still be based in fossil fuels. It makes sense to develop those fossil fuels here at home under the world’s toughest environmental regulations rather than to import oil from politically fraught regions with a higher carbon footprint. This would also create tends of thousands of jobs and create tens of millions of dollars (or more) in economic activity and new tax revenue.

LAT: Fracking-related earthquakes were reported in Oklahoma, and Ohio now requires seismic monitoring. Does fracking cause earthquakes?
Zoback: “There have been well-documented cases around the country where wastewater injection [post-fracking] has triggered slip on preexisting geologic faults that would have produced an earthquake someday anyway. You need to avoid injection into potentially active faults. […] The fear of fracking is being used as a scare tactic. There are environmental impacts, and our job is to do everything possible to minimize them, not just scare the public.”

The National Research Council (NRC) concurs that the practice of underground injection has been occurring for decades, is tightly regulated by the U.S. Environmental Protection Agency (EPA), and poses a marginal risk. The NRC concludes:

“Injection for disposal of wastewater derived from energy technologies into the subsurface does pose some risk for induced seismicity, but very few events have been documented over the past several decades relative to the large number of disposal wells in operation.”

The Los Angeles Times article further illustrates that scientists dismissed the recent attempts to draw connections between shale development and seismic activity well before the fear-riddled headlines began appearing. Zoback is quoted three years ago in the Stanford Reporter and the message remains the same:

“There have been fears that hydraulic fracturing fluid injected at depth could reach up into drinking water aquifers. But, the injection is typically done at depths of around 6,000 to 7,000 feet and drinking water is usually pumped from shallow aquifers, no more than one or two hundred feet below the surface. Fracturing fluids have not contaminated any water supply and with that much distance to an aquifer, it is very unlikely they could.”

The message resonated again during a Senate Committee on Energy and Natural Resources hearing in 2012:

“These microseismic events [from hydraulically fracturing a well] affect a very small volume of rock and release, on average, about the same amount of energy as a gallon of milk falling off a kitchen counter.”

Dr. Zoback, whom the Los Angeles Times notes is a dedicated environmentalist, agrees with most of the world’s leading scientists and with regulators when it comes to shale resource development. It is important to rely on the scientific method when tackling the world’s most pressing issues; and it is to the Times’ credit that it shared the insight of someone who truly understands the complex questions and processes that surround activists’ favorite scary word: fracking. Hopefully this will inspire other media outlets to follow suit and to involve independent scientists, regulators and other experts in their stories on shale development, rather than focusing on activists and their scare tactics.

No Comments

Post A Comment