Pennsylvania's Marcellus Shale Research Articles

Environmental justice and well waste disposal from oil and gas development in Pennsylvania

BACKGROUND AND AIM: Community socioeconomic deprivation (CSD) may be related to increased oil and natural gas development (OGD). We tested for distributive environmental injustice by examining whether waste disposal from OGD occurred disproportionately in areas with higher CSD in the Pennsylvania Marcellus Shale. METHODS: Data on well waste type, disposal method, and disposal location from 2005-2019 were downloaded from the Pennsylvania Geologic Survey’s Exploration and Development Well Information Network database. Analyses were restricted to waste disposed in-state and analyses were performed at the county subdivision level (n=1848). A CSD Index was created using 2005-2009 American Community Survey data. Regression analyses tested for nonlinear relationships, controlled for population density and well drilling prior to 2005, accounted for spatial dependence, and were stratified by urban/rural status. Logistic and linear regression analyses evaluated associations between CSD Index and receipt of any versus no well waste and cumulative volume of well waste deposited. RESULTS: Between 2005-2019, we identified 7.0 million tons of solid waste and 19 million barrels of liquid waste disposed of in Pennsylvania, with the highest volumes occurring in 2017-2019. We observed that a higher CSD Index was linearly associated with any well waste disposal (urban county subdivisions: OR= 1.13, 95% CI: 1.00, 1.28; rural county subdivisions: OR= 1.02, 95% CI: 0.97, 1.08) and with cumulative volume of waste disposed (urban: β = 5627 bbl-equivalent, 95% CI: -1957, 13211; rural: β = 6198 bbl-equivalent, 95% CI: 2007, 10390). Conclusions: We observed distributive environmental injustice with respect to well waste disposal in county subdivisions across the Pennsylvania Marcellus Shale. These results point to potential downstream disparities from OGD; future studies should investigate mechanisms that explain these disparities. KEYWORDS: Environmental Justice; Social Factors; Hydraulic Fracturing; Natural Gas

Towards better shale gas production forecasting using transfer learning

Deep neural networks can generate more accurate shale gas production forecasts in counties with a limited number of sample wells by utilizing transfer learning. This paper provides a way of transferring the knowledge gained from other deep neural network models trained on adjacent counties into the county of interest. The paper uses data from more than 6000 shale gas wells across 17 counties from Texas Barnett and Pennsylvania Marcellus shale formations to test the capabilities of transfer learning. The results reduce the forecasting error between 11% and 47% compared to the widely used Arps decline curve model.

Environmental enforcement and compliance in Pennsylvania’s Marcellus shale gas development

The rapid development of shale gas in the United States raises potential concerns about environmental impacts. This paper examines how environmental regulations are enforced in shale gas development in Pennsylvania's Marcellus Shale development and the resulting compliance behaviors, employing the economic literature of crime and punishment as the analytical framework. A three-level hierarchical linear model (HLM) is used to analyze the enforcement and compliance performance of regulators and shale gas operators, respectively, employing data spanning from 2011 to 2017. Significant variation in the environmental non-compliance exists between both wells and operators. The empirical results suggest progressive directions for adjusting environmental enforcement strategies in Pennsylvania and provide implications and references for other regions with similar shale gas ambitions.

The effect of firm size on fracking safety

Large firms are becoming increasingly dominant in the natural gas production industry. At the same time, regulators and environmental groups are concerned about potential environmental damage associated with hydraulic fracturing. However, small firms are protected from the full extent of their damages, while large firms must internalize a greater portion of their social costs. This paper examines the effect of firm size and liability on environmental safety in the context of hydraulic fracturing in Pennsylvania's Marcellus Shale across three dimensions of size. Impacts of firm size on safety are found across legal, regulatory, and brand dimensions of size with the largest effects being driven by changes in regulatory liability. These safety gains are sizable as violation rates would be approximately twice as high if firms at remained at 2008 sizes.

Agricultural Implications of Unconventional Natural Gas Development: Divergent Perceptions of Sustainable and Conventional Farmers

AbstractThis study explored sustainable and conventional farmers’ perceptions of unconventional natural gas development (UNGD) as it relates to agricultural production and distribution. Farmers (n = 200) in Pennsylvania's Marcellus shale region with gas drilling infrastructure on or near their farmland completed questionnaires; a subset (n = 16) of survey respondents participated in semi‐structured interviews. Findings revealed sustainable farmers faced unique negative impacts from UNGD, including greater sensitivity to environmental impacts, risks to organic certification and market participation, declining consumer confidence, and depreciating value of sustainable operations. UNGD‐related income and increased wealth within communities appeared to benefit agricultural production and sales, yet the most cited impact of UNGD on agricultural productivity was a decrease in crop production as farmland was used for UNGD. Findings also highlighted potential impacts on nascent local food markets in areas with UNGD, farmers’ expectations for outside oversight of UNGD, and limited transparency of environmental safety violations.

Busted amidst the Boom: The Creation of New Insecurities and Inequalities within Pennsylvania's Shale Gas Boomtowns

AbstractIn the middle of the first decade of this century new technological innovations enabled the extraction of natural gas through the use of hydraulic fracturing within gas‐bearing shale and other unconventional energy reserves. As a consequence, many places, often in economically lagging rural areas, saw dramatic change as they were socially and economically transformed through rapid natural resource development. Although scholarship on so‐called boomtown development has long explored social disruption associated with the sudden influx of workers and rapid economic development, this literature has tended to overlook the ways in which such development can create new poverty in the very midst of economic expansion. This article, through an examination of key informant interviews with low‐income residents and human service providers within Pennsylvania's Marcellus Shale region, discusses the contradictory processes by which new insecurity and social exclusions may be created precisely as a consequence of economic expansion associated with rapid natural resource development.

Geomechanical lithology-based analysis of microseismicity in organic shale sequences: A Pennsylvania Marcellus Shale example

Using an innovative workflow incorporating microseismic attributes and geomechanical well logs, we have defined major geomechanical drivers of microseismic expression to understand reservoir stimulation response in an engineering/geologic context. Microseismic data from a hydraulically fractured Marcellus well in the Appalachian Basin, central Pennsylvania, were sampled vertically through the event cloud, crossing shale, limestone, sandstone, and chert. We focused our analysis on the Devonian organic shale and created pseudologs of moment magnitude (Mw), b-value, and event count. The vertical moving-average sampling of microseismic data was completed such that the sample interval matched that of the geophysical well logs. This technique creates robust, high-resolution microseismic logs that show subtle changes in microseismic properties and allow direct crossplotting of microseismic versus geophysical logs. We chose five geomechanical properties to form the framework against which to interrogate the microseismic data: Young's modulus (YM), Poisson's ratio (PR), brittleness, lambda-rho, and mu-rho. Additionally, we included natural gamma as a useful measure of organic content. Having defined this microseismic-geomechanical crossplot space, we derived insights into the response of these units during hydraulic fracturing. Observations include: (1) larger magnitude microseismicity occurs in high PR rocks, and high event counts are found in low PR rocks; (2) low b-value (high in situ stress) is consistent with the occurrence of larger magnitude events and low event counts; and (3) YM and brittleness act as bounding conditions, creating “sweet spots” for high and low Mw, event count, and stress. In our crossplot space, there is a meaningful link between microseismicity and the elastic properties of the host rock. In light of this dependence of stimulation potential on elastic properties, the calculation of microseismic pseudologs at stimulation sites and application of our crossplot framework for microseismic-geomechanical analysis in unconventional shale will inform operators in planning and forecasting stimulation and production, respectively.

Fracked ecology: Response of aquatic trophic structure and mercury biomagnification dynamics in the Marcellus Shale Formation.

Unconventional natural gas development and hydraulic fracturing practices (fracking) are increasing worldwide due to global energy demands. Research has only recently begun to assess fracking impacts to surrounding environments, and very little research is aimed at determining effects on aquatic biodiversity and contaminant biomagnification. Twenty-seven remotely-located streams in Pennsylvania's Marcellus Shale basin were sampled during June and July of 2012 and 2013. At each stream, stream physiochemical properties, trophic biodiversity, and structure and mercury levels were assessed. We used δ15N, δ13C, and methyl mercury to determine whether changes in methyl mercury biomagnification were related to the fracking occurring within the streams' watersheds. While we observed no difference in rates of biomagnificaion related to within-watershed fracking activities, we did observe elevated methyl mercury concentrations that were influenced by decreased stream pH, elevated dissolved stream water Hg values, decreased macroinvertebrate Index for Biotic Integrity scores, and lower Ephemeroptera, Plecoptera, and Trichoptera macroinvertebrate richness at stream sites where fracking had occurred within their watershed. We documented the loss of scrapers from streams with the highest well densities, and no fish or no fish diversity at streams with documented frackwater fluid spills. Our results suggest fracking has the potential to alter aquatic biodiversity and methyl mercury concentrations at the base of food webs.

Redox Conditions Alter Biodegradation Rates and Microbial Community Dynamics of Hydraulic Fracturing Fluid Organic Additives in Soil–Groundwater Microcosms

One of the environmental risks associated with use of hydraulic fracturing stimulation technologies for oil and natural gas recovery is the potential release of used fluids into surface waters, soils, and groundwater that could contaminate drinking water resources. To better characterize biodegradability of organic additives, we developed a synthetic fracturing fluid (SFF) based on industry-disclosed formulas, compared its organic carbon composition to fluids used in Pennsylvania's Marcellus shale, and amended agricultural soil–groundwater microcosms with three different SFF concentrations to determine organic carbon degradation rates, changes in system biogeochemistry, and microbial community dynamics under aerobic and anaerobic conditions. Microorganisms indigenous to soils and groundwater were able to degrade between 70% and 92% of the amended dissolved organic carbon within 39 days, suggesting significant mineralization, transformation, or biomass assimilation of organic additives across anaerobic and aerobic redox conditions. Sequencing analysis of the 16S rRNA gene revealed a greater abundance of Pseudomonas in aerobic treatments and a higher relative portion of Desulfovibrio in anaerobic treatments amended with SFF, indicating that these taxa may be involved in SFF biodegradation processes under specific redox conditions. Results provide insight into biodegradability of hydraulic fracturing fluid organic additives in shallow agricultural soils and groundwater and biogeochemical processes that may attenuate their migration if accidentally released or spilled at the surface during hydraulic fracturing activities.

Fracking-Related Collective Action in Pennsylvania's Marcellus Shale Play

Fracking-Related Collective Action in Pennsylvania's Marcellus Shale Play

“If You Talk Badly about Drilling, You're a Pariah”: Challenging a Capitalist Patriarchy in Pennsylvania's Marcellus Shale Region

AbstractResearch on energy development is largely gender neutral, creating a need to illuminate how gender structures life in contemporary energy boomtowns. This study demonstrates how gender and the local economy are intertwined to perpetuate a capitalist patriarchy, which structures life for residents in these communities. The purpose of this article is to show that this economic‐gender structure creates tensions between those men and women whose gender performances reinforce hegemony and those who perform gender in direct opposition to resource extraction. I argue that men and women unconstrained by the capitalist patriarchy are better able to challenge its dominance than residents employed in the local economy. I use qualitative interviews (N = 39) with community residents and observations of community events in northeastern Pennsylvania's Marcellus Shale region as the primary methods of data collection. This study complements previous research by demonstrating the relationship between masculinity and femininity, showing the variability of gender in natural‐resource‐based settings and defining the hierarchal relationship among masculinities and femininities during periods of rapid energy development.

Spatial and temporal trends in freshwater appropriation for natural gas development in Pennsylvania's Marcellus Shale Play

AbstractWe characterize the appropriation of surface water for the extraction of natural gas from Pennsylvania's Marcellus Shale, and we examine the influences of these diversions on stream flows at 300 sites. Our analysis reveals that permitted withdrawals range from 50 m3/d to more than 18,000 m3/d and that water is taken from streams of all sizes, from headwater streams to eighth‐order rivers. Flow alteration varies inversely with watershed area and, for larger streams, is compounded by upstream withdrawals. The ratio of daily permitted withdrawal to median stream flow ranges from 0.0001 to unity, although low flows in most, but not all, smaller streams are protected by pass‐by flow requirements. Temporal changes in surface water withdrawals track gas well completion activity, rather than changes in operational strategies, and while reuse of wastewater has increased since 2009, freshwater accounted for 75% of water used in hydraulic fracturing through the peak in gas well completion activity.

A Localized Masculine Crisis: Local Men's Subordination within the Marcellus Shale Region's Masculine Structure

AbstractRural economic decline in the United States has contributed to new situational conditions under which men construct masculinity. Under these conditions, men define jobs and activities that were feminized during periods of economic stability as masculine. One exception to rural economic decline for men is economic growth associated with oil and natural gas development in geographical hot spots throughout the United States and around the world. Employment opportunities in the oil and gas industry largely favor men; however, it is unclear what effect this development has on local men because itinerant extralocal male workers complete most of the labor. This article conceptualizes masculinity as a social structure, and uses economic reports and theoretically distinct literatures on natural‐resource‐based masculinities and energy boomtowns to illuminate how multinational energy companies and a predominantly extralocal, male itinerant workforce in Pennsylvania's Marcellus Shale region cause adverse situational conditions for local men's constructions of masculinity. Within the new masculine structure, extralocal men's constructions of hegemonic masculinity become more important for defining the local socially dominant masculinity, which subordinates local men's constructions of nonhegemonic masculinities in their own communities. The article concludes with a discussion of how the oil and gas industry's hegemonic masculinity impedes sustainable economic development and community well‐being.

Techno-economic assessment of industrial CO2 storage in depleted shale gas reservoirs

The long-term storage of carbon dioxide (CO2) via injection into deep geologic formations represents a promising technological pathway to reducing greenhouse gas emissions to the atmosphere. Geologic storage in deep saline aquifers has been studied extensively, and the injection of CO2 for enhanced oil recovery (EOR) from conventional (porous and permeable) formations has been practiced for decades. This study is focused on developing a preliminary assessment of the economic feasibility of storing CO2 in depleted unconventional natural gas-bearing shale formations. Using a surrogate reservoir model (SRM) and a flexible environment for techno-economic analysis, this paper presents site-scale estimates of long-term CO2 sequestration costs in depleted shale gas formations and discussion of the likely major cost drivers. This analysis focuses on the transportation of CO2 from industrial point sources in the Pennsylvania Marcellus Shale region, and the transition of Marcellus wells from production to CO2 injection. This approach couples techno-economic analysis with reservoir simulation models to estimate costs associated with transportation, injection, CO2 separation and post-injection monitoring of CO2 storage permanence from large industrial point sources in depleted shale-gas reservoirs. We also consider potential revenue from incremental CH4 recovery (effectively enhanced gas recovery) in reservoir scenarios where such production is significant. The techno-economic model boundary includes pipeline transport from an industrial source (excludes the cost of capture of CO2 at that source), site preparation and CO2 flooding operations, and long-term monitoring and post-injection site care (PISC) at the storage site. Under an operational scenario where a Marcellus shale gas well is in primary production for 42years prior to the initiation of CO2 injection, it is estimated that CO2 could be transported and stored at a levelized cost of $40–$80 per metric tonne, in present value terms. These costs are shown to be highly sensitive to assumptions regarding well spacing, bottomhole pressure, CO2 transport distance and the future price of natural gas. In most of the scenarios considered, transportation and injection costs were dominant factors, while CO2 separation, pore space acquisition and post-injection site care/monitoring did not significantly influence levelized costs.

Opportunity, Ambivalence, and Youth Perspectives on Community Change in Pennsylvania's Marcellus Shale Region

Across vast swaths of mostly rural Pennsylvania, dramatic social, economic, and environmental transformations have occurred in the last five years as these regions have experienced a new natural resource boom in the form of unconventional natural gas extraction from the Marcellus Shale formation. While Pennsylvania's former Governor, Tom Corbett, and shale industry advocates hailed these developments as an economic godsend for Pennsylvania, others have raised serious concerns about the potential social, environmental, and economic consequences. In this paper, we examine youth perspectives in shale gas communities and how young people weigh their education and future prospects in light of local economic, environmental, and community change. We find that youth career decisions are often characterized by a deep ambivalence about the gas industry, its longevity, its capacity to provide desirable and local employment, and its ultimate effects on the livability and social sustainability of Pennsylvania's shale ...

Assessing impacts of unconventional natural gas extraction on microbial communities in headwater stream ecosystems in Northwestern Pennsylvania.

Hydraulic fracturing and horizontal drilling have increased dramatically in Pennsylvania Marcellus shale formations, however the potential for major environmental impacts are still incompletely understood. High-throughput sequencing of the 16S rRNA gene was performed to characterize the microbial community structure of water, sediment, bryophyte, and biofilm samples from 26 headwater stream sites in northwestern Pennsylvania with different histories of fracking activity within Marcellus shale formations. Further, we describe the relationship between microbial community structure and environmental parameters measured. Approximately 3.2 million 16S rRNA gene sequences were retrieved from a total of 58 samples. Microbial community analyses showed significant reductions in species richness as well as evenness in sites with Marcellus shale activity. Beta diversity analyses revealed distinct microbial community structure between sites with and without Marcellus shale activity. For example, operational taxonomic units (OTUs) within the Acetobacteracea, Methylocystaceae, Acidobacteriaceae, and Phenylobacterium were greater than three log-fold more abundant in MSA+ sites as compared to MSA− sites. Further, several of these OTUs were strongly negatively correlated with pH and positively correlated with the number of wellpads in a watershed. It should be noted that many of the OTUs enriched in MSA+ sites are putative acidophilic and/or methanotrophic populations. This study revealed apparent shifts in the autochthonous microbial communities and highlighted potential members that could be responding to changing stream conditions as a result of nascent industrial activity in these aquatic ecosystems.

School and Community Impacts of Hydraulic Fracturing Within Pennsylvania's Marcellus Shale Region, and the Dilemmas of Educational Leadership in Gasfield Boomtowns

Innovations associated with gas and oil drilling technology, including new hydraulic fracturing and horizontal drilling techniques, have recently led to dramatic boomtown development in many rural areas that have endured extended periods of economic decline. The Marcellus Shale play, one of the world's largest gas-bearing shale formations, lies beneath approximately two-thirds of Pennsylvania, including some of the state's most economically lagging rural areas. Spurred by a state-level policy environment favorable to unconventional gas extraction, drilling activity in the last five years has rapidly increased, often with profound social, economic, and environmental implications for communities. In this paper we use schooling as a particular analytic lens for understanding the dynamics of natural resource boomtown development, community change, and how these changes may affect educational and instructional decision making. Using data from interviews and focus groups with educators and administrators in Pennsylvania communities experiencing intensive natural gas development, we discuss the multiple organizational, curricular, and educational dilemmas school leaders face in the context of both rapid, unpredictable community change, and an educational policy environment unfavorable to place-sensitive educational responses to local change.

Field survey of health perception and complaints of Pennsylvania residents in the Marcellus Shale region.

Pennsylvania Marcellus Shale region residents have reported medical symptoms they believe are related to nearby Unconventional Natural Gas Development (UNGD). Associations between medical symptoms and UNGD have been minimally explored. The objective of this descriptive study is to explore whether shale region Pennsylvania residents perceive UNGD as a health concern and whether they attribute health symptoms to UNGD exposures. A questionnaire was administered to adult volunteers with medical complaints in a primary-care medical office in a county where UNGD was present. Participants were asked whether they were concerned about health effects from UNGD, and whether they attributed current symptoms to UNGD or to some other environmental exposure. There were 72 respondents; 22% perceived UNGD as a health concern and 13% attributed medical symptoms to UNGD exposures. Overall, 42% attributed one or more of their medical symptoms to environmental causes, of which UNGD was the most frequent. A medical record review conducted on six participants who attributed their medical symptoms to UNGD revealed that only one of these records documented both the symptoms in question and the attribution to UNGD. The results of this pilot study suggest that there is substantial concern about adverse health effects of UNGD among Pennsylvania Marcellus Shale residents, and that these concerns may not be adequately represented in medical records. Further efforts to determine the relationship between UNGD and health are recommended in order to address community concerns.

Local Impacts of Unconventional Gas Development within Pennsylvania’s Marcellus Shale Region: Gauging Boomtown Development through the Perspectives of Educational Administrators

Using survey and interview data gathered from educators and educational administrators, we investigate school and community impacts of unconventional gas extraction within Pennsylvania's Marcellus Shale region. Respondents in areas with high levels of drilling are significantly more likely to perceive the effects of local economic gains, but also report increased inequality, heightened vulnerability of disadvantaged community members, and pronounced strains on local infrastructure. As community stakeholders in positions of local leadership, school leaders in areas experiencing Marcellus Shale natural gas extraction often face multiple decision-making dilemmas. These dilemmas occur in the context of incomplete information and rapid, unpredictable community change involving the emergence of both new opportunities and new insecurities.

Wetland and stream mitigation: Application of a resource condition assessment protocol in the Pennsylvania Marcellus Shale

With the exploration and the production of the Marcellus Shale come inevitable unavoidable environmental impacts to the surface of the Earth and associated waters of the United States including wetlands and streams. Environmental impact assessment includes measurement of impacts to aquatic resources, much of which is associated with the production and transportation of Marcellus Shale gas to market. The Commonwealth of Pennsylvania has prepared a rapid resource condition assessment protocol that will be applied to determine the existing quality of Pennsylvania streams to assess impacts to those streams and to quantify appropriate compensatory mitigation for impacts to these water resources. This protocol, advanced by the Bureau of Waterways Engineering and Wetlands of the Pennsylvania Department of Environmental Protection, builds on prior work of the U.S. Army Corps of Engineers Norfolk District and the Unified Stream Methodology of the Virginia Department of Environmental Quality to provide a consistent and rapid condition assessment for projects to obtain water obstruction and encroachment permits, for water quality certifications, as well as general permits that affect waterways, floodways, and/or floodplains.