In efforts to understand the potential impacts of the Marcellus Shale extraction activities on stream health, we performed a baseline study on a focal pair of small streams in the Tenmile Creek watershed in Greene County, Pennsylvania. Bates Fork had intensive Marcellus Shale well drilling activity and several violations upstream from our study site. A tributary, Fonner Run, served as a control stream site with no drilling activity. Through two years of monitoring, we established baselines for water chemistry and biological communities of bacteria, fish and salamanders. In addition, we compared population genetic diversity of two darter species with microsatellite markers. Although no conclusive differences were found between the stream-pair, we established baseline parameters and gained insight into refining tools to detect the signature of Marcellus Shale extraction impacts on small streams in southwestern Pennsylvania. We conclude this chapter with lessons learned from this case study, future directions and suggestions for improved monitoring and detection of Marcellus Shale impacts on streams in southwestern Pennsylvania.

Historical data can be used to evaluate water impacts from unconventional oil and gas extraction. “Grey” literature measurements of water quality before, during, and after unconventional extraction activities offer a potentially powerful resource for the evaluation of water quality impacts, and these data have rapidly expanded with regulatory response to the unconventional boom. However, historical data are limited in the variety of measured constituents and require substantial effort to reconstruct, revisit, and re-evaluate. Ultimately, available data were limited as data from only a single county (Bradford) included constituents necessary to use the vast majority of these elemental ratio systems. Further, even when data were available, they were often measured with relatively poor sensitivity, precluding their use as early indicators of contamination. This case study accentuates the continued need to establish background conditions, particularly in regions that have accumulated historical impacts, and further, ensure these characterizations incorporate sensitive testing for known chemistries associated with emerging and novel processes.

My first interaction with Lynn was when I took her Evolution course in the spring of 1978. I had started graduate school in the biology department at Boston University the previous fall, as a master’s student. The department had listed my field of interest as “Exobiology,” as I had used the term in my application essay. It was taken from the title of Cyril Ponnamperuma’s edited volume (Ponnamperuma 1972), that I had fortuitously discovered in the biology department library of my alma mater, Fordham University. But I honestly had no idea that Lynn was involved with NASA. When we met in her office to talk about my interests, I told her I wanted to look for evidence of life in meteorites. She responded that I needed to go work with Bart Nagy, who was then at the University of Arizona. Seeing as I had just moved to Boston, I wasn’t too keen on going anywhere else. Thankfully, Lynn took me on and I was accepted into the PhD program.

The United States has an abundance of shale plays and unconventional oil and gas drilling now occurs in over 30 states. Major development has occurred in North Dakota, Texas, Louisiana, Arkansas, Michigan, Oklahoma, Wyoming, Colorado, Pennsylvania, Ohio, and West Virginia. The technological advances included the combination of horizontal drilling and hydraulic fracturing, new slick water formulations, and improvements in drilling technologies and fracking design such as “zipper fracking”. The upstream sector includes pre-drilling activities, pad preparation, drilling, hydraulic fracturing, and completion. The midstream sector includes pipeline construction and maintenance and processing facilities that separate the products of mixed gas. These processing facilities can be quite extensive, especially in Southwestern Pennsylvania, Eastern Ohio, and the panhandle of West Virginia where wet gas predominates. This review presents an overview of unconventional gas extraction in the Appalachian Basin as currently practiced in Pennsylvania, Ohio, and West Virginia.

The Energy Information Administration (EIA) has assessed 46 countries for their technically recoverable unconventional oil and gas reserves. They estimate the global shale gas reserves at 7,577 Tcf (trillion cubic feet) and the global shale oil reserves at 419 billion bbl (barrels). The 10 largest reserves for shale gas are in China, Argentina, Algeria, United States, Canada, Mexico, Australia, South Africa, Russia, and Brazil. The European Union also has significant deposits with the majority located in Poland and France. The 10 largest reserves for shale oil are in the United States, Russia, China, Argentina, Libya, United Arab Emirates, Chad, Australia, Venezuela, and Mexico. To date, only the United States and Canada have reached commercial level production for shale gas and oil, followed to a lesser extent by China and Argentina. Australia has seen its efforts concentrate on liquified natural gas (LNG) and export. Most other countries remain in the exploratory phase or have halted development. This chapter provides a brief review of the major shale gas and oil plays based on the extensive assessment done by the EIA, and the current status of their development.