Geology Reference
In-Depth Information
The study also includes five places that have been hydrofracked—the Bakken
Shale in Kildeer and Dunn counties, North Dakota; the Barnett Shale in Wise
and Denton counties, Texas; the Marcellus Shale in Bradford and Susquehanna
counties, Pennsylvania; the Marcellus Shale in Washington County, Pennsylvania;
and Raton Basin in Las Animas County, Colorado. Results of the study are expec-
ted in 2014. “The value of these tests is that they are really the first independent
review of what's happening from start to finish. It is a data set that doesn't really
exist right now,” Briana Mordick, a Natural Resources Defense Council scientist,
has said. 56
People on both sides of the debate agree that a broad and rigorous measurement
of hydrofracking's impact on groundwater supplies is long overdue. Groundwater
lies in deep aquifers far from sight, recharges slowly through precipitation from the
surface, and can extend through subterranean chambers for hundreds of miles. (The
Ogallala Aquifer, the nation's largest groundwater source, extends some 174,000
square miles beneath eight states. It has been in the news recently because the pro-
posed Keystone XL pipeline was originally designed to cross over it in Nebraska,
raising fears that an oil spill could contaminate the aquifer.) Once polluted, ground-
water is notoriously difficult to clean. The crucial aspect to such a study would be
a systematic sampling of the site prior to drilling, during drilling, and after drilling.
This is accomplished with monitoring wells drilled in and around a hydrofracking
site. The EPA is now in the midst of such a study.
To gauge the impact of hydrofracking on water supplies, the EPA is conducting
a landmark nationwide study of 24,925 wells that were drilled with the process
between September 2009 and October 2010. The agency opens its report with
the assertion: “Natural gas plays a key role in our nation's clean energy future.…
However, as the use of hydraulic fracturing has increased, so have concerns about
its potential human health and environmental impacts, especially for drinking wa-
ter.” 57 The study includes 18 research projects that will attempt to answer import-
ant questions about the use of water in five distinct stages of hydrofracking: from
water acquisition to chemical mixing, well injection, flowback, and produced wa-
ter, to wastewater treatment and waste disposal.
The study includes extensive mapping, a review of published literature, data
analysis, scenario planning, computer modeling, laboratory studies, and case stud-
ies. It will focus on identifying ways that hydrofracking could contaminate drink-
ing water on the surface and underground, including the role of elevated levels
of methane. The study will not address other sensitive questions, such as possible
links between hydrofracking and earthquakes or geochemical changes, however.
Search WWH ::




Custom Search