Marcellus Shale 101
Marcellus Shale. While the topic has been in the news a great deal lately, many people are not up to speed on this highly charged energy and environmental issue, and from all indications it will continue to be a big news story in Pennsylvania. Shale gas has become an increasingly important source of natural gas in the United States over the past decade, and some analysts expect shale gas to supply as much as half the natural gas production in North America by 2020. Millersville University has several professors who have expertise in areas that involve Marcellus Shale.
Dr. Lynn Marquez, a professor of geology in earth sciences, gives us the basics.
What is it?
Shale is a type of sedimentary rock. It is a fine-grained material. Marcellus is the name of the formation where it was originally found or described. The Marcellus Shale formation in Pennsylvania is named after a town in New York.
How is it formed?
The natural gas in the shale originated with microscopic plant life from the Devonian time period. Sediments were laid down when the Appalachian Mountains were forming — 355 to 415 million years ago. Shale gas is natural gas produced from shale. The natural gas is produced as the organic matter is heated to temperatures of around 150 degrees Celsius.
We’ve known about the Marcellus Shale formation for a long time but companies didn’t know how to get the gas out in a cost effective way. As technology has improved, it has become economically viable to drill it.
Will oil shale be viable as well?
Oil shale will not be economically viable anytime in the near future because it requires so much energy to separate oil from shale. Oil is different from natural gas. Oil is more viscous – making it more difficult to separate from the fine-grained particles of shale. Gas is easier to capture through the hydraulic fracturing, or fracing (pronounced “fracking”) process. More details on this process follow.
Huge amounts of water (approximately five million gallons per well) will be used and contaminated to extract the natural gas from the shale. The environmental consequences will be severe in some areas. Associated with that is the question, how will Pennsylvania pay for clean-up? According to the Pennsylvania Budget and Policy Center, roughly half of the natural gas is likely to be extracted from a well in the first five years with a typical life span of a well to be 40 years. The gas companies are asking for severance tax on a producing well to be delayed three years or more, which is a huge mistake in my opinion because it provides no revenue for environmental clean-up. The natural gas producers will continue to make money on the Marcellus Shale even with a severance tax that most states including West Virginia and New York, employ.
Dr. Sam Earman, professor of geology in earth sciences has expertise in fracing.
Is it fracking or fracing?
First, “fracking” (with the “k”) is a pretty recent construction, mostly used in lay articles. Most geologists and petroleum engineers use “fracing” (no “k” but pronounced the same way).
What is fracing?
Fracing is short for hydraulic fracturing. In fracing, fluid is injected into a well at very high pressures, and the fluid flows out from the well and creates fractures in the rocks it moves through. Fracing is used in “tight” rocks. A tight rock is one in which the open spaces that oil or gas can move through are very small. An analogy for trying to pump oil or gas from a tight rock would be trying to get a stadium full of people out through a few large “dog doors”–even assuming people could wriggle through the dog doors, it would be difficult and take a long time. If we blasted open several large openings in the stadium walls (analogous to what is done in fracing), we will be able to get the stadium emptied out much more quickly.
Is fracing common?
Fracing is a very commonly used method for extraction of oil and natural gas, and has been used all over the world. Oil and gas can almost always be extracted without fracing, but the question is whether it is economical or not. A single deep well needed for oil and gas extraction can often cost into the millions of dollars to drill. If you only get a slow trickle of oil or gas from the well, you may not be able to recoup your exploration and drilling expenses during the life of the well. In some cases, fracing might make the difference between a well that will pay back its costs and one that will be a money loser by increasing the flow rate of oil or gas.
How much water is used?
Exactly how much water is used depends on a number of factors, but it’s not uncommon for millions of gallons of water to be used on a single well. The use of large amounts of water is a concern in and of itself (this water could otherwise be used for crop irrigation, domestic water supply, etc.), but the main environmental concerns relate to the various additives in the fracing fluid. Fracing fluids are almost always water-based, but they contain many additives.
‘Proppants’ (material such as sand that’s injected with the fluid to keep the fractures created during fracing open) are one common type of additive, but various chemicals are added for other reasons (e.g., to increase the viscosity of the fracing fluid or to help eat away at the rock). These additives can often be health hazards if consumed. In addition, many companies consider their blend of chemicals proprietary information, and don’t want to list everything that’s being used to prevent competitors from using their recipe.
Dr. John Wallace, a biology professor is interested from an aquatic standpoint.
What is your knowledge/involvement with Marcellus Shale?
I first became involved with this issue two years ago when I heard a Pa., Fish & Boat Commission biologist introduce the topic at a conference. The interest was just beginning, and there were very few wells dug at that time. The state agencies had little-to-no knowledge as to the impact on the environment two years ago. The political pressure was huge on Governor Rendell to fast track exploration of this “new” domestic energy resource, hence permits were being granted before the proper environmental policies were in place or research support generated to inform the public on the risks to the environment.
In the fall of 2009, I attended a Marcellus Shale Conference at Penn State University, sponsored by the Pennsylvania environmental watchdog organization, PennFuture. In January 2010, I assisted with planning the policy conference here at Millersville University last spring. We brought in Dr. Jay Parrish, state geologist, who spoke on Marcellus Shale geology and drilling as well as Michael Wood, who spoke on the economics of the Marcellus Shale with special emphasis on the severance tax.
Currently, I plan to consult with several professionals, some of whom were my former students now working with a local environmental engineering firm as well as a colleague, to identify six study sites and comparable control sites to begin an intensive monitoring program designed to evaluate biological, physical and chemical aspects in these streams to more fully understand the impacts, if any, of shale gas drilling or water withdrawal on ecosystem functioning and overall water quality. A team of students will accompany me this spring and summer to these sites and will assist with this project during their remaining time at Millersville University.
How are students involved?
Students are involved at multiple levels with my research in this area. First, there are the former students I mentioned earlier who are employed at a local environmental engineering firm; they are helping identify field sites and gain permissions to conduct this type of research. Second, I have a team of students in my lab who will be assisting with conducting the actual field research. This research will involve sampling macroinvertebrates, collecting water chemistry data as well as assessing the habitat (both instream and riparian) associated with drill site streams and control streams (i.e., streams not associated with Marcellus drill sites).
Finally, I am assisting a local high school student who will be conducting her science fair research examining the difference in diatoms and other algae between Marcellus Shale drill sites and non-drill sites in Tioga County. The idea with this multi-tiered project is to create a cadre of former, current and possibly future students collaborating on an applied research endeavor that will hopefully generate a database for other researchers in this field.
How much water is used?
Each drill pad requires approximately five million gallons of freshwater that is withdrawn from either nearby streams that meet state regulations for permission to withdraw without harming aquatic organisms. This water is trucked into the site and stored in a holding basin. Once the water is used to frac the shale, there are several problems associated with the “used” water. First, the additives used are extremely toxic to the environment. Second, initially, it was thought that wells retrieved approximately 25-30% of the used frac water, but, now that number is significantly lower, only approximately 10% or less is returned. Third, this water not only has the toxic heavy metals, etc., used to frac the shale, but it is extremely high in salinity and could be radioactive.
Companies are stating that they are recycling this used frac water, but if they are only getting 10% of the five million gallons, this effort is not proving to be comforting. Water that is lost appears to be reaching aquifers, with many locations already claiming to have severely compromised water quality. In fact, the Monongahela River near Pittsburgh was recently given a poor water quality rating due to the excessively high salinity values. If streams in these regions suffer too much withdrawal, the impact on these coldwater fisheries could be devastating. There have already been more than a thousand tanker trucks fined for violating numerous environmental regulations with regards to waste water storage, transport, etc.
What are concerns you have with this project?
Gas companies are threatening to leave if the state imposes a severance tax; this could not be further from the truth. Without a severance tax, the companies will not be held financially liable in the event (not if, but when) an environmental disaster occurs. Pennsylvania is one of 15 states without a severance tax. It would be a huge mistake to stop this legislation. The 2010 state administration enacted a moratorium on any future drilling permits until the necessary environmental research could be done to determine the risks to the environment. The governor-elect stated — no less than 24 hours after being elected — that he was going to lift this moratorium immediately once he took office.
Besides identifying field sites and initiating sampling procedures, I am co-organizing a symposium on human and associated health issues involving benthic aquatic organisms and their environment for the North American Benthological Society annual conference to be held in Providence, Rhode Island in May 2011. As one of the co-organizers, I will also be presenting a talk on the potential impacts of Marcellus Shale gas drilling on our streams and rivers. I also hope to be able to take one or more of these students to this meeting. Our research will be on-going with samples scheduled to be collected every spring in order to establish a long-term monitoring effort designed to evaluate the potential impacts on stream ecosystems in these regions.