(John Kemp is a Reuters market analyst. The views expressed are
By John Kemp
LONDON Dec 12 It is time to stop
demonising hydraulic fracturing. Oil and gas production is a
messy, dirty business that produces all sorts of harmful waste.
But the chemicals used in hydraulic fracturing are no more
dangerous than those frequently used in acidizing and other
conventional well treatments.
Fracking poses no more risk to the environment than
production from conventional wells, which the industry and
regulators have learned to manage successfully in recent decades
to minimise the impact on local communities.
Much of the political opposition to fracking seems to be
driven by general hostility to fossil fuels, and a lack of
understanding about how oil and gas are produced from
conventional wells, rather than by any special dangers
associated with hydraulic fracturing itself.
The risks commonly cited by opponents (contamination of
drinking water, disposal of salty waste water and chemicals from
fracked wells, and seismic activity) are just as much of a
problem when drilling ordinary wells.
FRACKING NOT NEW
Differences between conventional and fracked wells are
overstated. Fracking went mainstream long ago. It is part of a
spectrum of techniques for improving flow rates and the ultimate
amount of hydrocarbons recovered from a broad range of oil and
The oil industry has been using explosives to fracture
reservoir rocks and improve oil flow to the foot of wells since
From the middle of the 20th century, the dangerous practice
of dynamiting wells was gradually replaced by hydraulic
fracturing using high pressure fluid injection. The first frack
job was performed in Kansas' Hugoton field as long ago as 1947.
By 2002, long before shale gas and oil had emerged on the
political radar, hydraulic fracturing had been used a million
times in the United States, according to a recent survey by the
National Petroleum Council (NPC).
Up to 95 percent of wells are now fracked, accounting for 43
percent of total U.S. oil production and 67 percent of natural
gas production, according to the NPC ("Prudent Development:
Realising the Potential of North America's Abundant Natural Gas
and Oil Resources," September 2011).
Fracking is routinely used to improve recovery from a wide
range of oil and gas wells, not only those drilled into tight
formations such as the Barnett shale in Texas and North Dakota's
Critics claim fracking poses a heightened risk to freshwater
water aquifers that provide vital supplies for households and
In most cases, however, oil and gas-bearing formations occur
thousands of feet below the drinking water aquifers and are
separated from them by one or more impermeable layers of rock
capping the reservoir. If they were not, the oil and gas, being
lighter than water, would already have migrated up into the
freshwater zone or even escaped at the surface.
Fracking risks damaging cap rock and allowing oil, gas or
fracking fluids to flow up into the drinking water layer. But
given the large distance separating the oil and gas layers from
freshwater, and the large number of other stresses on oil and
gas reservoirs, including formation damage from drilling, the
risks are not significantly higher than for conventional wells.
Critics have expressed concern about chemical additives used
in fracking. In many cases, fracking companies have tried to
keep the cocktails commercially confidential, adding to the
suspicion, though this is changing with voluntary and mandatory
disclosure via registries such as FracFocus.
But the industry has long pumped all sorts of unpleasant
chemicals down conventional wells. Hydrochloric and hydrofluoric
acids are commonly used to enlarge the natural pores in the
reservoir or fracture the formation. After an acid job, spent
acid, dissolved rock and sediments are pumped out of the well
during the backflush.
The drilling mud used in every well routinely contains
diesel or synthetic oils, as well as chemical additives such as
foaming agents, thinners, bactericides and emulsifiers to
regulate various aspects of performance, which must be carefully
removed from the well after use and disposed of safely.
A typical frack job uses 43,000 gallons of frack fluid and
68,000 pounds of sand, according to Professor Norman Hyne of the
University of Tulsa. But a massive frack job could employ more
than 1 million gallons of fluid and 3 million pounds of sand
("Petroleum Geology, Exploration, Drilling and Production",
Carefully disposing of huge volumes of waste water is
therefore essential to avoid contaminating surface watercourses
and subsurface aquifers. But again the waste disposal problem is
In every oil and gas formation, hydrocarbons are mixed with
large amounts of salty water, which is brought to the surface
along with the oil and gas. Oilfield brine shares the pores in
the reservoir rock with the oil and gas, and can have up to 20
times the salt content of sea water.
Conventional wells produce huge amounts of oilfield brine,
which is typically re-injected into deep salt-water aquifers to
ensure safe disposal (often as part of a programme to maintain
pressure and production rates in the oil reservoir). Waste water
produced by fracking poses exactly the same problems.
Hydraulic fracturing has been blamed for a swarm of small
earth tremors in Oklahoma and near the town of Blackpool in
northern England. But managing subsidence and other problems
associated with oil and production (as well as sub-surface
mining) is another well-established problem that is not special
Even without fracking, extraction of oil and water from the
giant Wilmington oil field in Long Beach, California, caused the
surface of the town to subside 9 metres. Oil production left
much of the city below sea-level, until a massive
water-injection programme was undertaken to prevent further
slippage, and dikes were be erected to protect it from
In the North Sea, the Ekofisk production platform had to be
jacked up in the 1980s after the seabed subsided several metres,
leaving its boat deck below the water line.
Fracking operations are often more visible and have a larger
surface footprint in local communities than conventional oil and
gas wells. Hundreds of trucks and tankers are needed to haul
water and sand to the site and carry waste away afterwards.
Fracking has also opened up oil and gas formations in parts
of North America and elsewhere that have not experienced
large-scale drilling before, or at least not for many decades.
Nevertheless, drilling is not impossible even in highly
One of the most prolific petroleum basins on the planet lies
under the cities of Los Angeles, Long Beach and Beverly Hills in
California. The Beverly Hills High School has 19 oil wells on
campus pumping several hundred barrels of oil per day.
There will be occasional spills and accidents. No form of
energy production is without some risk. The challenge is to
contain it to an acceptable level and compensate the victims
when things go wrong.
For the industry and regulators, the biggest challenge will
be maintaining and improving standards during the largest
drilling boom in 30 years. But that is a challenge caused by
rapid growth, not the fracking technology itself.
(Editing by Jason Neely)