Natural Gas Q&A with Bill deRosiers – Part I

Questions raised by ordinary citizens about natural gas provide an excellent opportunity for some natural gas Q&A. The following questions arose during a recent Careers in Energy program at Valley View High School by a student who has an interest in responsible energy development but with some legitimate concerns about natural gas. I thought my answers might be useful to others with similar concerns. Therefore, I am restating his questions and my answers below and in subsequent posts.

Hydraulic fracking uses millions of gallons of water.  A staggering 85% is stripped from the hydrologic cycle and permanently blasted into the shale.  Wastewater, one of the largest causes of water pollution, can at least be treated, but fracking actually removes this water entirely! I find this disturbing that an industry has the authority to take water out of the water cycle… a delicate system that no one should “own” as every living thing depends on it for survival. From a cardinal at Goose Pond Scout Reservation, to the freshwater paramecium, to a child in the Congo, every living thing depends on water. I understand the combustion of methane yields CO2 (a greenhouse gas by the way) and some water vapor, but how is the industry making up for this 85% lost water?

Good question. Every company handles water sourcing and wastewater management a little differently, but you would be surprised that the majority of the companies in Pennsylvania recycle and reuse. Cabot works with a company called Comtech Industries, which specializes in treating all sorts of fluids. Right now, 99% of the fluid that comes out of a Cabot well (approximately 20% in the first few weeks and another 20% over the life of the well) is treated and reused. Through the use of this process Cabot has been able to offset its fresh water tremendously since we voluntarily started reusing waste water a few years back.

The process Cabot uses to treat its water is called chemical precipitation. It’s one of many different treatment processes; other companies use reverse osmosis or distillation. Since we are reusing the water now and for the foreseeable future, Cabot cleans the water to a certain spec but not drinking water quality.  Basically, barium, calcium, and sand/shale cuttings that come back up with the water are identified and removed through the treatment process. While salt is present, there is no point in removing it since we are reusing it in a formation with high salinity. Individuals touring our facility common ask: why don’t we treat for the fracturing chemicals? The reason, they are so diluted the water quality spec is not impacted; really they’re not even detectable.

This video is a demonstration of Cabot’s treatment process at Comtech’s field lab in Dimock. I shot the video three years ago, but the process has remained the same since:

Given the rate of innovation in this industry, it is foreseeable that companies like Comtech could work to develop a process to treat the water back to a different, drinking quality spec. Comtech and many of its counterparts in the waste water treatment industry are experienced in treating complicated fluids from a variety of different sources. Think about waste water treatment facilities that process medical waste and industrial waste or everything that is poured down the sink or flushed in the toilet in your town or city. Waste water fluids from numerous industries are a part of our everyday society. In the oil & natural gas business these fluids are managed and treated responsibly under the direction of the proper state and federal regulations.

Now for a quick discussion on your concerns about water being removed from the water cycle, I can tell you it’s quite the opposite when you look at the chemistry behind the combustion of natural gas. When you burn natural gas (CH4) it will produce carbon and water molecules; this is a scientific fact easily verified. To calculate just how much, go to this document from the Colorado School of Mines. I won’t go into all of the science here, the basics are presented below:

CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O(I)

To quantify this equation, over 1 billion cubic feet (Bcf) of natural gas, when combusted, will produce 11,088,859.6 gallons of water into the atmosphere. A conventional well in West Virginia might produce 1 Bcf of gas during its lifetime but a Cabot Marcellus Shale well will, according to our reservoir engineers, yield production of 16 Bcf on average over its multi-decade life. This means more than 100,000,000 gallons of water could potentially be put back into the water cycle once all of the gas is combusted from a typical Cabot Marcellus well; far more than originally used to stimulate the well.

Furthermore, Cabot produces over 1.5 Bcf per day in the Marcellus. In Pennsylvania, combine production is over 16 Bcf. So, scientifically speaking, I think we are more than compensating for the water usage.

If you are still really concerned about responsible water use, which you should be, I encourage everyone to visit the Susquehanna River Basin Commission’s (SRBC) website. The SRBC is the regulator agency responsible for permitting and monitoring water use throughout Cabot’s operations in the Marcellus. The regulations set forth by this interstate compact are very strict and if it’s drought conditions, operators cannot take any water.

Now that we have discussed the industry use of water, management of wastewater and the reintroduction of water back into the environmental cycle, I think it’s important to recognize how much water is drawn by other industries and users in the same geographic region: golf courses, agriculture and non-oil and gas industries, by far, are larger users of water. What’s more concerning is that agriculture introduces fertilizers and golf courses introduce pesticides into the water which naturally work their way back into lakes, streams, rivers and aquifers. But the proper regulatory agencies monitor these sources of waste consumption and wastewater creation too, protecting our environment and health. I’m not trying to point fingers; instead, I’m looking to foster perspective.

Potential Gas Committee Reports Resource Evaluation
Economic Impacts of the Atlantic Sunrise Pipeline Project
Bill desRosiers

Raised in Highland Falls, New York, William desRosiers learned about responsible resource development, firsthand, as a part of his family's mining business. William received his B.S. in Management, B.A.in History and MBA from Misericordia University. He currently serves in External Affairs for Cabot Oil & Gas Corporation. His primary responsibilities include strengthening media relationships, managing company-run fundraising programs, building better community relations and representing Cabot every chance he has.

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