The Health Impact Assessment of New Energy Sources: Shale Gas Extraction
Natural gas extraction from shale rock formations, which includes hydraulic fracturing (commonly referred to as “hydrofracking”), is increasingly in the news as the deployment of the technologies has expanded, rural communities have been transformed overnight, public awareness has increased, and regulations are developed. The expanding use of shale gas extraction across the United States occurs in a context in which there are demands to reduce greenhouse gas emissions, desires to decrease dependency on foreign energy, controversies over other energy sources like offshore drilling, nuclear energy, biofuels and the proposed Keystone pipeline, and slower advancements of renewables like wind and solar energy technologies. Public health was not brought into discussions about shale gas extraction at earlier stages; in consequence, the health system finds itself lacking critical information about environmental public health impacts of the technologies and able to address concerns by regulators at the federal and state levels, communities, and workers employed in the shale gas extraction industry.
Shale gas extraction in the United States is an opportunity because of the existence of of thermagenic methane reservoirs in geologic formations such as the Marcellus and Utica shale formations. Formerly inaccessible, the higher cost of petroleum based fuels has motivated efforts to extract and market this methane at depths up to 7,000 feet. Because of the geology of the shale—at depths of at least 100 ft and with gas stored within natural fractures or joints rather than in large pools—conventional gas extraction techniques are not effective. Hydrofracturing utilizes technological advances in horizontal drilling and fracturing techniques. It differs from conventional gas extraction techniques in that it involves: higher volume of fracking fluids (millions of gallons of fluid versus less than 100,000 gallons of fluid) to stimulate gas release; directional drilling to access more natural joints; the use of “slickwater” to allow for pumping over 1.5 to 2.0 miles of horizontal pipe; and multi-well pads. Combining these technologies has made gas extraction from organic-rich shale formations economically feasible in the last 15 years.
In many states, the number of permits issued for fracking has increased exponentially in the last few years. Other states, such as New York, have required an individual, site-specific environmental review while the state formulates its own guidance or even, in the case of Maryland, issued a moratorium on permits until such approaches can be developed. Generally regulators have focused on the potential hazards with the fracturing fluid (“slickwater”), which is water with chemicals added to reduce the friction of the water in underground channels. Hydrofracking chemicals include those designed to keep fracture channels opened (proppants and biocides), gelling agents (to increase the viscosity), anti-corrosives, friction reducers, and acids. Regulators also have been concerned about how the expansion of shale gas extraction activities increases noise, air, and light pollution in an area, and the potential for accidental releases of hazardous material into the air and groundwater. Also, these activities have been known to create local seismic activity. In public health, there is an increasing awareness of the importance of a “health in all policy” approach to protecting human health while ensuring economic growth. Central to this is the use of health impact assessments to inform decisions by providing a structured process that uses scientific data, professional expertise, and stakeholder input to identify and evaluate the public health consequences of proposals. In 2011 the NRC published a report “Improving Health in the United States: The Role of Health Impact Assessment” that provides recommendations for how properly-conducted health impact assessments can help minimize adverse health effects and optimize beneficial ones. If anything, the pressures that have led to the rapid deployment of hydrofracturing for shale gas extraction – high costs of energy, economic pressures, and the need to reduce greenhouse gas emissions – will only grow more acute with time. The advancement of new technologies for energy production requires a holistic approach to sustainable economic growth that fully considers health impacts.
This workshop will focus on shale gas extraction to explore the health impacts of emerging energy technologies and the use of health impact assessments to assess and identify ways to mitigate potential health impacts. Through presentations and discussions, it is expected that Roundtable members, scientists, decision makers, and other participants will become better informed on the potential health impacts of hydrofracking, be updated on the learn lessons from ongoing health impacts assessments, and be better positioned to consider safeguards to protect the public's health from emerging energy and other technologies.
This workshop is one in a series of workshops sponsored by the Roundtable on Environmental Health Sciences, Research, and Medicine. The Roundtable was established in 1998 to provide a mechanism for parties from the academic, industrial, and federal research perspectives to meet and discuss sensitive and difficult environmental health issues in a neutral scientific setting. The purpose is to foster dialogue and is not intended to provide recommendations.
A live webcast of the workshop will also be available for those who are unable to attend.