Ohio Study Warns of Pennsylvania Wastewater
Akron Beacon Journal
23 January 2013
By Bob Downing
AKRON, Ohio -- The volume of drilling wastes from Pennsylvania's
Marcellus Shale is growing and threatening to overwhelm existing
waste-handling infrastructure in Ohio and other states, according
to a study released Tuesday.
Ohio's 179 injection wells for disposing of briny waste might not
be sufficient for the Pennsylvania waste, plus wastes from Ohio's
developing Utica Shale, said Brian Lutz, assistant professor of
biogeochemistry at Kent State University, who led the analysis
while he was a postdoctoral research associate at Duke University.
"The overall volume of water that now has to be transported and
treated is immense," he said. "It threatens to overwhelm the
region's wastewater-disposal infrastructure capacity."
The wastes in play include flow-back water, produced immediately
after hydraulic fracturing, or fracking, plus brine, or production
water, generated after the fracking is done and the well goes into
production. Such wastes generally are similar with a few key
differences.
The liquid wastes can contain significant amounts of salts and
total dissolved solids; low-level radiation and toxic heavy metals
picked up from underground rocks; oils and grease; leftover toxic
chemicals used in fracking; and certain volatile organic
compounds, including benzene.
Pennsylvania has about 6,400 Marcellus Shale wells that have been
drilled and another 3,500 that have been permitted. In comparison,
Ohio has about 500 wells permitted in the Utica Shale, of which
200 have been drilled.
Mr. Lutz said Pennsylvania generated about 20 million barrels
(each holding 42 gallons) of wastewater in 2011. About 7 million
barrels were shipped to Ohio injection wells.
Ohio is projecting that its injection wells handled nearly 14
million barrels in 2012, up from 12.8 million barrels in 2011.
(Final figures have not been compiled). More than half of that
volume came from Pennsylvania and West Virginia.
Ohio cannot ban such wastes because they are interstate commerce
protected under the U.S. Constitution. It is unknown exactly how
much injection capacity the state can handle.
"This is the reality of increasing domestic natural gas
production," said Martin Doyle, a professor of river science at
Duke. "There are significant trade-offs and environmental impacts
whether you rely on conventional gas or shale gas."
Mr. Lutz reported that Marcellus Shale horizontal wells that have
been fracked are producing less wastewater per unit of gas than
conventional wells would produce.
Fracked natural gas wells in the Marcellus Shale produce only
about 35 percent as much wastewater per unit of gas recovered as
conventional wells, according to the analysis that appears in the
journal Water Resources Research.
"We found that on average, shale gas wells produced about 10 times
the amount of wastewater as conventional wells, but they also
produced about 30 times more natural gas," said Mr. Lutz, who only
recently came to Kent State. "That surprised us, given the popular
perception that hydraulic fracturing creates disproportionate
amounts of wastewater."
The researchers at Kent State and Duke analyzed gas production and
wastewater generation for 2,189 gas wells in Pennsylvania, using
data reported by the industry to the state's Department of
Environmental Protection.
Mr. Doyle said the researchers were surprised that drillers
classified most of the wastewater as brine, not fracking flowback
water.
Studies have shown that brine can be as difficult to treat as many
of the chemicals used in fracking fluids, he said.