It has long been known that natural gas was trapped in the tiny pore spaces that comprise shale rock, but that knowledge was useless. Until recently there was no economically feasible way to extract this gas. However, in the past decade our ability to recover natural gas buried a mile or more beneath the earth in these shale deposits has increased. Advances in horizontal drilling which allows a vertical well to turn and run thousands of feet laterally through the earth combined with advances in hydraulic fracking, the pumping of millions of gallons of water laced with proprietary chemicals into shale at high pressure to release the natural gas stored in the pore spaces have increased our ability to recover natural gas from that shale. This combined with the increase in the price of natural gas has spurred the race to develop wells to exploit the natural gas from a series of major shale gas deposits in North America that could not have been viable without these advances in drilling and fracking. The Fayetteville shale, the Haynesville shale, the Marcellus shale reserves all in the United States and the Horn River shale in Canada are now accessible. At the current rate of natural gas consumption North America is reported to have a 100-year supply (at the current rate of use) of proven, producible reserves.
Natural gas is now seen as an abundant domestic energy resource. When it burns, natural gas emits the lowest amount of carbon dioxide per calorie of any fossil fuel and burns cleanly because of this natural gas could be the “bridge fuel” in the long-term transition away from fossil fuels to renewable energy or whatever the future and science will discover. In the 1990’s natural gas, sold for $2 per million BTUs after peaking in 2005 natural gas is now about $4 per million BTUs, making the extraction of shale gas viable and profitable. The U.S. uses natural gas to produce 21 % of its electricity. Coal is used to product 48 % of electricity in the United States and is still much cheaper than natural gas for generating electricity, but new regulations by the EPA on carbon emissions could decrease that financial advantage because coal burns dirtier than natural gas. Recent ambitious plans to convert the nation to renewable energy: build nuclear plants and solar and wind farms, were made under the assumption that natural gas prices would average $7 to $9 per million BTUs. At that level, electricity prices would have been high enough to make wind and nuclear power look affordable. Now, with natural gas at $4 per million BTUs and more gas reserves announced each year, many of these projects suddenly look too expensive. Shale sourced natural gas could profoundly change the future of our nation and world we live in; however we need to remember that the gas still is a limited resource and be cautious about what other impacts fracking might have on our other resources especially the hydraulic balance.
Though there has been tremendous concern for the potential direct adverse impact that fracking may have on drinking water, geologists and engineers believe that there is little risk that the fracking “water,” a mix chemicals and water, will somehow infiltrate groundwater reserves though a fissure created by the fracking. It is believed though not documented and tested that the intervening layers of rock would prevent a fissure from extending thousands of feet to the water table. There are other risks in how we build wells and fracture the shale. Documented contamination to drinking water wells due to seepage of fracking water into drinking water wells through improperly sealed or abandoned drilling wells can be controlled to some extent by recommendations made in the report of the Shale Gas Subcommittee of the Secretary of Energy Advisory Board. The report had a rational approach to regulation recommending disclosure, testing, evaluation and modification of regulation and practices based on the information and data obtained. It assumes information and data will be gathered and analyzed. That is not being done.
Though the energy companies are beginning to gather baseline data for drinking water wells in the areas being fracked, the data collection is not ongoing nor broad enough. The data that is being collected is not adding to the base of knowledge, but rather I suspect to demonstrate that stray gas was a pre-existing condition of the drinking water wells. What is needed is an ongoing monitoring and data collection of the potential impacts to our water supply from hydraulic fracking. Drilling requires large amounts of water to create a circulating mud that cools the bit and carries the rock cuttings out of the borehole. After drilling, the shale formation is then stimulated by hydraulic fracking, using up to 3 million gallons of water. Data needs to be gathered on the impact to water resources of supplying water for the construction of thousands of wells per year. For gas to flow out of the shale, nearly all of the water injected into the well during fracking must be recovered and disposed of. Though less than 0.5% by volume, the proprietary chemicals are 15,000 gallons in the waste from the typical 3 million gallon hydro fracking job. The chemicals serve to increases the viscosity of the water to a gel-like consistency so that it can carry the propping agent (typically sand) into the fractures to hold them open so that the gas can flow. Determining the proper methods for the safe disposal of the large quantities of this fracking fluid that may also contain contaminants from the geological formation including brines, heavy metals, radionuclides and organic contaminants and monitoring the impact from this disposal must also be done. The impact of so much waste water on our water resources must be measured and monitored. Finally, care must be taken to avoid degradation of watersheds and streams from the industry itself as large quantities of heavy equipment and supplies are moved on rural roads and placed on concrete pads. The watersheds must be monitored. http://pubs.usgs.gov/fs/2009/3032/pdf/FS2009-3032.pdf
U.S. Geological Survey (USGS) collects, monitors, analyzes, and provides scientific understanding about natural resource conditions, issues, and problems. The USGS employs 10,000 scientists, technicians, and support staff that serve the Nation by providing reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect our quality of life. The USGS is an amazing national resource that we have failed to fully utilize in the understanding of the impacts of hydraulic fracking. The USGS should determine the parameters that need to be monitored for a base line and on an ongoing or periodic basis and industry should provide that data in a usable format to the USGS. For once let’s develop a resource carefully and correctly without scaring the earth or damaging our water supply. We’ve lost our margin for error.
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