34
The most common frack fluid chemical additives are methanol, isopropanol,
crystalline silica, 2-butoxyethanol, ethylene glycol, hydrotreated petroleum distillates, sodium hydroxide, hydrochloric acid, ammonium chloride, ammonium and
sodium persulfate, glutaraldehyde, and polyacrylamide (Soeder et al. 2014). The
additives serve to clean perforations, reduce friction losses, provide corrosion resistance, inhibit scale build-up, and suppress microbes.
The EPA compiled a consolidated list of over 930 chemical compounds used or
found in hydraulic fracturing, including 132 chemicals present in produced waters
(USEPA 2016). Sources included federal and state government documents, industryprovided data, and other reliable information. Listings of frack additives on a wellby- well basis are also posted on the FracFocus website (http://fracfocus.org/), a
cooperative venture between the Ground Water Protection Council and Interstate
Oil and Gas Compact Commission. The information is posted voluntarily by service
companies in some cases, and it is required by state permit in others.
The claim that “hundreds” of chemicals are added to frack fluid is a misunderstanding. While a great many chemicals have been tried over the history of hydraulic fracturing, no service company adds hundreds or even dozens of chemicals to
any individual frack. Different chemicals may be used in different stages, but
advances in hydraulic fracturing technology have reduced the total number of
chemicals used to less than half a dozen in a single frack stage (Soeder et al. 2014).
Many of the chemicals present in groundwater that people blame on hydraulic fracturing are actually coming from elsewhere (McMahon et al. 2015, 2016, 2017, 2019).
There are a number of concerns about chemical additives to fracks. Many of
these compounds are new, and little is known about how they will react in the environment. Most of the formulations are proprietary trade secrets, so information
about what is being added and in what quantities is not readily available to researchers. Although many of the additives are posted on the FracFocus website, the
descriptions are often vague and generic.
The process by which an organic chemical breaks down over time in the environment is called natural attenuation (NA), and knowing the individual steps, daughter
products, and reaction rates is important for remediating a contamination event. NA
information currently exists for things like hydrocarbon fuels, chlorinated solvents
and other organic compounds, but it is very sparse for the chemical additives to
hydraulic fracturing fluid. The response to a spill or a leak of frack chemicals would
be problematic at best with the current lack of understanding about how they behave
in the environment. This will be explored further in coming chapters.
One other frack additive that has some issues is sand. Hydraulic fracturing in
shale requires less proppant than other kinds of fracks because “asperities” or natural rough spots are created on fracture walls that help prop open the fractures when
pressure is released. However, because of the high volume of hydraulic fracturing in
shale, even these so-called “light sand” fracks end up requiring a lot of proppant. To
work well as a proppant, the sand must be composed of evenly-sized, well-rounded
quartz grains with a high compressive strength.
The Jordan Sandstone in Wisconsin is one of the few formations in the U.S. that
consistently meets the standards for frack sand. Concerns have been raised by the
2 What Is Fracking?
The most common frack fluid chemical additives are methanol, isopropanol,
crystalline silica, 2-butoxyethanol, ethylene glycol, hydrotreated petroleum distillates, sodium hydroxide, hydrochloric acid, ammonium chloride, ammonium and
sodium persulfate, glutaraldehyde, and polyacrylamide (Soeder et al. 2014). The
additives serve to clean perforations, reduce friction losses, provide corrosion resistance, inhibit scale build-up, and suppress microbes.
The EPA compiled a consolidated list of over 930 chemical compounds used or
found in hydraulic fracturing, including 132 chemicals present in produced waters
(USEPA 2016). Sources included federal and state government documents, industryprovided data, and other reliable information. Listings of frack additives on a wellby- well basis are also posted on the FracFocus website (http://fracfocus.org/), a
cooperative venture between the Ground Water Protection Council and Interstate
Oil and Gas Compact Commission. The information is posted voluntarily by service
companies in some cases, and it is required by state permit in others.
The claim that “hundreds” of chemicals are added to frack fluid is a misunderstanding. While a great many chemicals have been tried over the history of hydraulic fracturing, no service company adds hundreds or even dozens of chemicals to
any individual frack. Different chemicals may be used in different stages, but
advances in hydraulic fracturing technology have reduced the total number of
chemicals used to less than half a dozen in a single frack stage (Soeder et al. 2014).
Many of the chemicals present in groundwater that people blame on hydraulic fracturing are actually coming from elsewhere (McMahon et al. 2015, 2016, 2017, 2019).
There are a number of concerns about chemical additives to fracks. Many of
these compounds are new, and little is known about how they will react in the environment. Most of the formulations are proprietary trade secrets, so information
about what is being added and in what quantities is not readily available to researchers. Although many of the additives are posted on the FracFocus website, the
descriptions are often vague and generic.
The process by which an organic chemical breaks down over time in the environment is called natural attenuation (NA), and knowing the individual steps, daughter
products, and reaction rates is important for remediating a contamination event. NA
information currently exists for things like hydrocarbon fuels, chlorinated solvents
and other organic compounds, but it is very sparse for the chemical additives to
hydraulic fracturing fluid. The response to a spill or a leak of frack chemicals would
be problematic at best with the current lack of understanding about how they behave
in the environment. This will be explored further in coming chapters.
One other frack additive that has some issues is sand. Hydraulic fracturing in
shale requires less proppant than other kinds of fracks because “asperities” or natural rough spots are created on fracture walls that help prop open the fractures when
pressure is released. However, because of the high volume of hydraulic fracturing in
shale, even these so-called “light sand” fracks end up requiring a lot of proppant. To
work well as a proppant, the sand must be composed of evenly-sized, well-rounded
quartz grains with a high compressive strength.
The Jordan Sandstone in Wisconsin is one of the few formations in the U.S. that
consistently meets the standards for frack sand. Concerns have been raised by the
2 What Is Fracking?