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Known knowns, known unknowns, and unknown unknowns

Vol. 14, No. 10 — May 9, 2012

Former Secretary of Defense Donald Rumsfeld was talking about the Iraq War when he famously said, "[T]here are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns — there are things we do not know we don't know."

This same thinking could apply to the potential impact of the unconventional natural gas industry on air quality in Pennsylvania.

There are known knowns.

Drilling for shale gas differs significantly from shallow gas drilling. The development of unconventional shale gas involves larger rigs, more diesel-powered engines to run the rigs and fracking operations, more methane pollution during completion wells, more trucks to service the well pads, more tanks with vents that store production fluids, more pipelines to transport the gas, more compressor stations and pneumatics to move the gas along the pipelines, and more treatment facilities to separate liquids before delivery of the gas to the marketplace. All of these activities contribute pollutants to the air that we breathe.

We know that the primary air contaminants generated by shale gas development are nitrous oxides (NOx), volatile organic compounds (VOCs), very fine particulate matter (PM2.5), methane (CH4), and air toxics such as benzene, toluene and formaldehyde. And we also that these pollutants harm public health — NOx and VOCs form ozone that increases asthma attacks; particulate matter causes heart attacks and strokes; methane contributes to global warming; and air toxics are, well, toxic.

Finally, we know that other areas of the country have documented that shale gas development has impacted local and regional air quality. Extensive oil and gas development in parts of rural Wyoming and Utah, where little other industrial activity occurs, has led to dangerous ozone levels — higher than those recorded in some of the most heavily polluted United States cities. Last year, families in Wyoming's Upper Green River Basin experienced over 40 days in which ozone concentrations exceeded the current health standard. In Utah's Uintah basin, residents experienced twice this number of unhealthy ozone days, with one monitor located in Ouray recording 40 exceedances alone. A 2009 study found that summertime emissions of smog-forming pollutants from oil and gas sources in the Barnett Shale were roughly comparable to emissions from all of the motor vehicles in the Dallas-Fort Worth area. In 2010, the Texas Commission on Environmental Quality (TCEQ) measured acute concentrations of toxic benzene that exceeded the state's health-based risk levels at two exploration and production sites in the Barnett Shale area of Texas.

Unlike rural Wyoming and Utah, Pennsylvania air, of course, is already less than pristine because of pollution from coal-fired power plants and heavy industrial activities. That means there is a smaller margin between healthy and unhealthy air, as compared to overall air problems observed in rural Wyoming and Utah.

This brings us to the known unknowns.

Eight years into development of our own shale gas play, Pennsylvania citizens still have no accurate data on air emissions from the shale gas industry, and no system in place to comprehensively monitor overall air quality throughout the Marcellus and Utica shale regions of the state. The new oil and gas act, Act 13, requires the gas industry to submit an annual inventory of air pollution from operations and explain how the data was calculated or estimated. However, neither Act 13 nor DEP's recent request for that data establishes a uniform methodology for estimating air emissions from natural gas operations.

In forming a working group to address estimates of greenhouse gases, the American Petroleum Institute freely acknowledged that development and use of uniform methodologies was critical to accurately estimating air pollution from the natural gas industry. With no quality assurance being exercised by DEP, and no uniform methodology required by Act 13, the data that was to be submitted by March, but is now delayed, may be of questionable use in any case. To complicate matters, because DEP continues to exempt drilling operations from any permitting requirements under its regulations, it has no accurate measurements of air emissions. And DEP still has not put in place a comprehensive, long-term monitoring program to measure air quality throughout the shale gas play areas of Pennsylvania. So, we not only lack accurate estimates of what pollution is released into the air from natural gas operations, we also have no accurate picture of existing air quality in those areas undergoing the most active shale gas development.

Other states have done substantial work on methodologies for estimating air pollution from the gas industry, and measuring air quality in and around shale gas development. The California Air Resources Board has published test protocols that it has developed with industry to accurately estimate emissions from the natural gas industry. And the Texas Commission on Environmental Quality established a comprehensive monitoring system that makes use of automated gas chromatography (GC) samplers — as well as other sampling techniques — to measure, analyze the level of pollutants — including air toxics (VOCs) — throughout its major shale gas regions, and report that information to the public. In the Barnett shale area of Dallas/Fort Worth alone, Texas has 13 GC monitors that sample and analyze the air for toxic pollution every hour of the day continuously. Texas makes this data available to the public through its website in real time. Both California and Texas offer examples of fair and reasoned approaches to get valid data about the affects of natural gas development on local and regional air quality.

Natural gas promises to reshape our energy landscape and Pennsylvania's economy. And developed with the right environmental safeguards and monitoring of impacts, natural gas offers distinct air quality benefits — especially when compared to the alternative of coal-fired power plants. But that mantra can only be recited in a vacuum for so long. The DEP lags far behind other states in obtaining accurate estimates of air pollution by the shale gas industry, and even further behind in monitoring existing air quality in areas most likely affected by that industry. Until we determine these known unknowns, we cannot even fathom what the unknown unknowns might be.

Eight years after it opened its doors to shale gas development, Pennsylvania continues to assert that public health and the environment are being protected. Eight years later, it is fair to ask whether that assertion is based on good facts and science, considering what the DEP knows to be unknown.

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