Whitesburg KY
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Will natural gas ‘bonanza’ destroy our water supply?




To the Editor:

As our nation attempts to move toward increased energy independence, interest in “unconventional sources” has soared. Natural gas extraction from shale formations is one such example. Letcher County lies within the Appalachian Shale Basin and most everyone in the county has by now noticed all the orange and pink flags along their roadsides. Extensive seismic surveys are presently being conducted in our region. I have spoken with several survey crews and have come to the conclusion from these discussions that our region is now poised in the starting blocks for a tremendous boom in natural gas recovery.

Conventional gas reservoirs are characterized by large volumes of gas trapped within impermeable rock layers. These pockets of gas are fairly straightforward to exploit. Unconventional gas occurs in formations where gas is actually attached to clay and slate particles. The gas is thinly spread out within the bearing rock formation and must be hydraulically forced from those subsurface resting places into a centralized location in order to make it a commercially viable venture. This involves drilling bore holes down which liquid nitrogen is pumped into the formation. The process is called “fracking” because the liquid nitrogen literally fractures the rock. This enables the gas to be freed from the formation through countless artificially induced fractures.

After the formation is sufficiently fractured, commercial gas production from shale beds generally requires the formation to be “stimulated.” Stimulation involves using nitrogen-based foams and/ or a concoction called “slickwater” which is pumped into the formation in order to chemically liberate the gas and create a pressure gradient which mobilizes the gas towards a collection point.

Slickwater is a mixture of water, sand, and additives. The additives include biocides, surfactants, friction reducers, scale inhibitors and hydrochloric acid. The exact ingredients are considered proprietary by the gas companies and consequently are not subject to public review, despite being pumped under our collective feet. The quantities of water utilized for natural gas recovery via stimulation are tremendous and these stimulations are repeated multiple times for most recovery projects. It is estimated that about 10 percent of shale bed gas is initially recovered and that multiple restimulations produce another 10 percent. Each subsequent restimulation requires 25 percent more slickwater than the previous stimulation.

The Marcellus Shale Formation in Pennsylvania is currently undergoing intensive gas recovery operations. Many complaints are being expressed by the citizenry living in the region. Heavy truck road damage is substantial and a problem Letcher County has already experienced on a very limited scale. Uncontained “flow back” is the major concern. Flow back is wastewater that returns to the surface from the stimulated underground formation. All flow back is supposed to be collected and trucked to an approved disposal site or specially designed wastewater treatment facility because flow back is almost always high in salts and heavy metals. Currently in Pennsylvania there is a shortage of such approved disposal sites/facilities and legitimate concerns have been expressed about where these tremendous volumes of flow back are actually ending up. Complicating matters even more, the control of flow back for recovery and disposal is by no means a precise operation. Surface blowouts and seepage into streams and adjacent subsurface aquifers is proving to be a major problem.

Sulfides are common in and around shale beds. When sulfides buried deep underground are exposed to oxygen from fracking and stimulation operations, an acidproducing reaction takes place. Acidic waters from these operations then cause a phenomenon called “mental mobility.” The acidic waters dissolve naturallyoccurring quantities of the following metals present in the surrounding rock and soil: arsenic, cadmium, copper, cobalt, chromium, iron, molybdenum, nickel, mercury, vanadium, and zinc. Once toxic metals are mobilized, they contaminate surface and ground water as well as soils. No longer safely locked up deep underground by chemical bonds, these liberated heavy metals circulate through ecosystem pathways where they bioconcentrate in creatures high in the local food chain — primarily fish and creatures that feed on fish. A disorder known as endocrine disruption exchange develops in people and animals routinely exposed to concentrations of heavy metals.

It is crucial for Letcher County residents to be informed and clear-headed about the tradeoffs involved with unconventional natural gas recovery in shale bed formations. With these gas leases you will get predictable water quality problems associated with acidification and metal mobility. Tainted aquifer and surface waters do not recover quickly. Once sulfides and pyrites are exposed to oxygen through bore holes and fracking, the acid reaction will continue until all exposed sulfides are dissolved. Acidification and metal mobility may continue for hundreds of years. Aquifers lying above shale bed gas may form a hydrodynamic trap. This liquid lid of water containing the gas is simply drained.

Drinking water wells may go dry or recharge very slowly. Local citizens must monitor their wells and test their water periodically. Local government must be alert, responsive and proactive with respect to these important issues of public safety.

It is state and local government which ultimately controls access to gas lease well heads via the state/county road system. If this nation has learned one thing from our current economic crisis, it is that the “quick base” short-term profit motive (greed) leads to longterm ruin. Without a broader sense of responsibility, the profit motive alone is simply criminal behavior.

JAMES LEWIS Whitesburg


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