Brandon Ellingson (NRC)
Abigial Nash (Sustainable Food and Farming)
Irina Polunia (Environmental Science)
For the people of Aztec, New Mexico, the introduction of hydraulic fracturing, or fracking, brings promises of job creation and lower energy prices (Barbee, 2015). Hydraulic fracturing is the process of extracting oil and natural gas from rocks in tight geological formations through high pressure pumping of water and various chemicals (McJeon et al., 2014). The resulting so-called ‘transitional fuel’ obtained via fracking is arguably cleaner than coal, emitting 45% less carbon dioxide per energy unit than coal production (Lomborg, 2012). For the United States, fracking provides an opportunity to achieve energy self-sufficiency and reduce carbon dioxide emissions. Furthermore, hydraulic fracturing is cheaper than coal production (Schneising et al., 2014). Despite the idealistic promises of the fossil fuel industry, fracking instead exceeds the threshold where it would contribute less greenhouse gas emissions than coal production (Heath et al., 2013, Sanchez et al., 2015) and leads to substantial air pollution due to natural gas leakage around extraction sites. This is the case for Aztec, New Mexico, where fracking is a hazard to human health and puts the climate and community benefit of fracking into question (Barbee, 2015).
The local residents of Aztec, New Mexico call the hydraulic fracturing sites a “toxic tour of hell” (para. 6) and many have come together to take action against the 20,000 natural gas wells that surround their community (Barbee, 2015). A local grandmother, Shirley McNall, describes many issues due to the air pollution: from a nauseating smell that plagues their community to a plethora of ailments, like asthma. McNall cites a study done in Colorado that found high concentrations of methane and other volatile organic compounds in people living close to fracking sites. These dangerous gases could potentially cause cancer, birth defects, and asthma, amongst other things. McNall concludes: “we need the energy, we need the jobs, but we need our health. If we don’t have our health, all the jobs and money aren’t worth a damn” (Barbee, 2015, para. 19).
As hydraulic fracturing becomes more extensive around the United States, the resulting natural gas, composed mostly of methane and other hydrocarbons, can serve as transitional fuel as the world moves toward green energy (Howarth et al., 2014). However, in 2010, the Environmental Protection Agency (EPA) issued an alarming report that put the climate benefit of fracking into question, stating concern about the release of fugitive methane emissions (Howarth et al., 2014). This has since prompted a surge of studies investigating hydraulic fracturing. Although most studies are not yet conclusive (Lan et al., 2015, Townsend-Small et al., 2015, Lavoie et al., 2015, McJeon et al., 2014, Karion et al., 2015, Lyon et al., 2015), many show that fracking has potential to cause substantial harm to the environment through fugitive methane emissions (Krupp, 2014).
Fugitive methane emissions are emissions of methane from pressurized equipment due to leaks and other unintended or irregular releases of the gas from industrial activities (Hope, 2014). Methane gas is a greenhouse gas that is 84% more potent than carbon dioxide, meaning that upon release, it absorbs more heat from the sun. Even though methane gas stays in the atmosphere for a shorter period than carbon dioxide, it is a dangerous greenhouse gas that increases the rate of climate change (UC San Diego, 2002). Therefore hydraulic fracturing, an emitter of methane gas, has potential to cause substantial harm to the environment through the increase in global temperature from methane emissions.
Methane escaping from hydraulic fracturing sites result from a number of factors. First, methane gas leaks from equipment, such as wells and pipelines, found in fracking sites. And second, methane gas escapes during the hydraulic fracturing process through various techniques (Howarth et al., 2014). A study conducted by Tollefson (2013) looked at multiple fracking wells in Colorado and found that a single well loses a total of 4% methane gas to the atmosphere. Howarth et al. (2014) found similar results; a total of 3.6-7.9% methane gas from shale-gas production escapes to the atmosphere over the lifetime of just one well.
Equipment, such as wells and pipelines, used at hydraulic fracturing sites are one source of methane leakage into the surrounding atmosphere (Krupp, 2014). A study conducted by the Government Accountability Office, or GAO, (2010) concluded that “0.3% to 1.9% of the lifetime production of a well is lost due to routine venting and equipment leakage” (pg. 13). A typical well consists of 55-150 connections to equipment like heaters, meters, dehydrators, compressors, and vapor-recovery apparatus, of which many have potential leaks (Howarth et al., 2014). Moreover, GAO (2010) found that pneumatic pumps and dehydrators were a major part of the problem since they were designed to purposefully vent gas. Routine venting refers to the process where methane is purposefully released into the atmosphere as a byproduct in well completion, well maintenance, pipeline maintenance, and tank maintenance. A typical well can last for about 40 years, sometimes even less depending on well location, and therefore well completions and maintenance are ongoing.The longer the well is run, the more a well can experience equipment leakage and would require venting for maintenance (Earthworks, 2013). The 0.3% methane emissions found by GOA (2010) reflects the best available technologies and techniques that are expensive and rarely used by natural gas companies unless required to do so by the state. This data, all collected within the U.S., does not include estimates in cases of accidents or emergencies, all of which are yet to be studied (GAO, 2010). On a global scale, Howarth et al. (2014) found that pipeline leakage alone releases ~2.5-10% of methane gas. These estimates are found using a technique that involves measuring the difference between the volume of gas at the wellhead and the quantity of gas actually purchased and used by the consumer (Howarth et al. 2014).
The Environmental Protection Agency, or EPA, conducted a similar study that focused on the methane released from specifically the valves and compressors used in fracking. The EPA determined that previous data greatly underestimated the methane leakage from valves and compressors. In fact, chemical injection pumps that are wellheads used to keep pipelines flowing and for neutralizing corrosive material, emitted methane that was twice as high as EPA’s previous estimates. The EPA concluded that high methane leaks from valves and compressors were most likely due to poorly constructed well casings and weak cement (Krupp, 2014). With so much inconsistency in the data, is truly difficult to understand the full spectrum of methane emissions from wells and pipelines, although it is proven to be a considerable amount.
The actual techniques used in the hydraulic fracturing process are another contributing methane emitter. The EPA (2012) estimated that around 1.9% of methane gas is lost from just the fracking process. The study attributes this loss to two particular processes, flow-back fluids and the ‘drill-out’ stage. As large quantities of water are pumped into the rocks, a significant amount of water called flowback fluids return to the surface after a few days or weeks that contains high quantities of methane. This methane then can evaporate and add emissions to the global system. This process is the leading cause of methane leakage in the fracking process alone.
The EPA (2012) study also found the ‘drill-out’ stage to be a contributor to methane emissions. In the ‘drill-out’ stage, “the plugs set to separate fracturing stages are drilled out to release gas for production” (p.281). This results in 0.33% methane emissions attributed to the ‘drill-out’ stage alone. Combining methane losses associated with both flow-back fluids (1.6%) and ‘drill-out’ stage (0.33%), the EPA concluded that a total of 1.9% methane is emitted as a result of the fracking process alone (Howarth et al., 2014).
Aside from the techniques used in the fracking process, small amounts of methane can leak out through the processing, transport, and storage of natural gas. Although the processing of natural gas occurs only in specific natural gas sites; in areas of occurrence, the resulting fugitive methane emissions is around 0.19% (Shires et al., 2009). The methane emissions for transport and storage is difficult to quantify, for there are more factors to consider. Moreover, there are limited studies in this area; however a study conducted by Lelieveld et al. (2005) computed an overall loss rate of 1.4%-3.91%. This is most likely a lower limit due to the limited data available.
In summary, methane emissions from the well and pipeline leaks is between 0.3-1.9%, from the techniques used in the fracking process is around 1.9%, and from processing, storage and transport about 1.4-4.1%. In total, the amount of methane emitted from hydraulic fracturing per well is about 3.6-7.9%. (Howarth et al. 2014) All three sources, individually, produce seemingly little amounts of methane emissions per well, however methane emissions are additive. There are approximately 1.7 million hydraulic fracturing wells in the United States as of 2015, therefore the total methane emissions from the United States alone is colossal (Kelso 2015).
According to the National Oceanic and Atmospheric Administration (NOAA), methane concentrations are increasing, with 2014-2015 being greatest increase in global methane concentrations at about 11.5 ppb/year, compared to 5.7 ppb/year previously observed from 2007-2013 (Butler & Montzka, 2016). A recent study conducted by Harvard University concluded that “the United States alone could be responsible for between 30-60% of the global growth in human-caused atmospheric methane emissions since 2002 because of a 30% spike in methane emissions across the country” (Magill, 2016, para. 1). The sudden increase in methane concentrations are likely from many sources, however, the largest source of methane emissions is from natural gas and petroleum systems (EPA, 2010). Despite the overwhelming impact of methane, oil and natural gas industries continue to expand. The evidence shows that methane gas leaks from fracking techniques, equipment, storage, and distribution. In fact, it is safe to say that almost every aspect of hydraulic fracturing releases some methane gas. In order to deter and reduce the United States contribution to greenhouse gas emissions, we propose a multi-part solution, focusing on the fracturing components and new fracturing sites.
We, first, propose a 5 year ban the development of new hydraulic fracturing sites, with existing sites serving as sites for research. This approach will allow the current economic activity surrounding these fracturing regions to continue while further research into methane mitigation is examined. Within the last 5 years, multiple states put forth effective bans, however these regulations faced major resistance and would likely be difficult to instill nationwide. New York and Vermont, along with several towns in Colorado, placed a temporary ban on hydraulic fracturing (Krupp, 2014). Lafayette, Colorado placed a ban on the creation of new gas and oil wells, while allowing the current sites to continue (Krupp 2014). While a full ban is more effective at reducing fugitive methane emissions from fracturing, it would not be feasible to spread nationwide. We anticipate that banning the spread of fracturing wells will be met with much less resistance and will be successful at initiating this ban on a large scale. Our proposal focuses on finding the middle ground between commercial interests and environmental risk, while allowing research to determine the effect fugitive methane emissions, and most importantly to mitigate the risk of increased contribution to global greenhouse gas emissions
In May 2016 the EPA proposed a set of regulations to prevent air pollution and further fugitive methane emissions. This plan describes effective methods of reducing fugitive emissions caused by malfunctioning equipment (EPA, 2016). We believe these regulations would be effective nationwide while providing benefit both the fracturing industry and the environment. These regulations along with our proposed temporary ban will be the best option to mitigate the harm associated with fracturing while also allowing this industry to prosper.
The EPA would require owners of natural gas sites to develop and implement a leaks monitoring plan using optical gas imaging equipment or other approved methods. This proposal also requires owners or operators of well sites to conduct surveys of a variety of components including valves, connectors, pressure-relief devices, closed vent systems, compressors and storage tanks. For recently modified wells the survey must be completed within 60 days of the change, and for existing sites this must happen twice per year. If any violations are found the well has thirty days to fix the issue or will be forced to stop production. Lastly. the EPA’s rules create a pathway for the EPA to approve alternative leak monitoring technology that proves to be just as effective. For instance, if a company proves the effectiveness of their technology it may be approved by the EPA (EPA, 2016). In order to reduce push back against the EPA’s regulations we propose that grants shall be given to fracturing wells to install the technology necessary for monitoring of leaks.
We acknowledge the apparent economic benefits associated with the fracturing boom within the United States. “The U.S. fracking revolution has caused natural gas prices to drop 47% compared to what the price would have been prior to the fracking revolution in 2013” (para. 2) Similarly, on average, the United States citizen is saving 150$ a year as a result of this natural gas fracturing boom (Dews, 2015). There is no question whether or not increased fracturing benefits both the natural gas industry and the energy consumer. The proposed regulations will not deter those benefits but rather enhance production efficiency for the natural gas companies.
As previously stated, Howarth et al. (2014) concluded that an average of 6% of methane per well from shale-gas production escapes to the atmosphere. Therefore, by reducing these fugitive emissions, fracking companies will not only reduce their contributions to greenhouse gas emissions, but will have larger profit margin due to increased production. From 2011 to 2014 the U.S. Energy Information Administration (EIA) monitored the production of 7 of the largest fracturing regions in the U.S.. These 7 regions constitute above 92% of the overall production for the U.S., and represent the large majority of fracturing activity nationwide. The average daily production for these 7 regions per well is 5237 thousand cubic feet. About 6% of this daily average would equate to ~314 thousand cubic feet of methane per well lost to the atmosphere. In 2016, the EIA estimated the average cost for a thousand cubic feet of natural gas directly from the producers to be $3.61, therefore the average monetary loss per well per day is $1,133.54 or $413,000 annually (EIA, 2016). The costs of implementing monitoring technology and replacing ineffective equipment should be miniscule compared to the loss of profit most wells are currently experiencing. Once taking into consideration the help of federal grants to reduce the installation cost of monitoring technology and the projected reduction of methane loss from leakage, we believe our proposed regulations will receive less opposition from natural gas companies and prove to be an effective mean of climate change mitigation.
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