equipped with sensors to measure total emissions in a given
EDF anticipates all will be submitted for publication in
peer-reviewed journals. The overall effort is scheduled to be
completed in late 2014.
The initial study report noted that findings showed higher
emissions from pneumatic controllers and equipment leaks
than EPA emission estimates. There was significant geographic variability in emissions from pneumatic pumps and
controllers, researchers said.
The 190 onshore gas sites used for measurements involved the Gulf of Mexico coast, Rocky Mountains, and Appalachian regions.
Emission measurements were performed for 27 well completion flowbacks, 9 liquids unloadings, 4 well workovers,
and 150 production sites of which 489 wells involved hydraulic fracturing.
“One important result from the measurements…is that
current EPA estimation methods overpredict measured
emissions,” the study said in its findings on unloadings.
“There are multiple methods of unloading a gas well, some
of which do not result in emissions.”
The UT-led study involved sampling performed for un-
loadings in which an operator manually bypassed the well’s
Researchers said the overall implication is “a large uncertainty” in the national emissions from gas well unloadings.
“It is also clear from the data that properly accounting for
unloading emissions will be important in reconciling emission inventories with regional ambient measurements.”
Study finds no fracing problems
in Inglewood oil field
A comprehensive study of Plains Exploration & Production
Co.’s Inglewood oil field in southern California’s Los Angeles
basin found no adverse effects from two hydraulically fractured test wells.
Emphasizing that every basin has unique characteris-
tics and concerns, Daniel R. Tormey, who led the study by
Cardno ENTRIX of Los Angeles for Plains E&P and the Los
Angeles County Department of Regional Planning, said, “I
believe this is the first study to comprehensively look at the
effects of fracing.”
The peer-reviewed October 2012 study quantified 14 dif-
ferent categories of physical and environmental effects of
two specific frac jobs at the existing oil and gas field in Los
Angeles County’s Baldwin Hills area, Tormey said at a Sept.
12 Washington, DC, briefing.
The wells were vertically drilled, but used higher water
pressures common in modern frac jobs, he noted during the
briefing cosponsored by the American Petroleum Institute
and the US Chamber of Commerce’s Institute for 21st Cen-
Tormey and his study partners, Megan Schwartz and
Molly Middaugh, found unique conditions in their study
area that might not necessarily apply elsewhere. “When you
take a close look, the LA basin pops out as the exact opposite
of rural Pennsylvania, where so many people have their own
private water wells,” he explained. “Two thirds of the water
used in the LA basin comes from the Colorado River or the
Sierra Mountains in northern California.”
They still had to measure drinking water because of
concerns residents raised after seeing a homeowner set
fire to water from an indoor tap in the documentary movie
“Gasland,” Tormey said. “Facts have a longer row to hoe than
fear,” he observed.
Not a source
Groundwater beneath the 1,000-acre Inglewood oil field,
which Standard Oil discovered in 1924 and Plains E&P
has operated since December 2002, is not a drinking water
source but must meet that standard, according to the study.
“Routine tests by the water purveyor show the community’s water supply meets drinking water standards, including
the period of high-rate gravel packs and conventional hydraulic fracturing as well as the first high-volume hydraulic
fracture in September 2011,” it said. Tormey said about 20
groundwater monitoring wells there have been taking measurements from various depths for about 4 years.
“Apart from arsenic, which is naturally high [in LA basin
groundwater], the analyzed constituents meet drinking wa-
ter standards,” the study said. “Before-and-after monitoring
of groundwater quality in monitor wells did not show im-
pacts from high-volume hydraulic fracturing and high-rate
To study ground movement and seismicity, Tormey and
his associates did microseismic and vibration monitoring
and used data from a nearby California Institute of Technol-
ogy accelerometer. “The microseismic intensity was not suf-
ficient to induce seismicity,” he said. “Where it occurred, it
was linked to produced water injection.”
Tests conducted before, during, and after fracing and
high-rate gravel packing showed no effects on the wells’ steel
and cement casings, the study said. Plains E&P has an on-
going well integrity test program under way at the field, it
“Methane analyzed in soil gas and groundwater, as well as
carbon and hydrogen isotopic rations in methane at the