8
evidence is called religion, not science. Pop culture and social media tend to treat all
viewpoints as valid, but considering an idea like the flat Earth to be a valid alternative viewpoint when it is based on zero evidence only ends up overshadowing many
of the real scientific problems in the world. An anti-science response to issues like
climate change, plastic in the oceans, loss of tropical rainforest, spread of contagious disease, the extinction of species, and yes, even fracking with policies based
on beliefs rather than data can have serious consequences. At best, the very existence of the problem is denied, and nothing gets done. At worst, governments and
regulators may focus on fixing the wrong thing and people die from disasters or
diseases.
1.2 Perceptions of Risk
Many of the concerns about the perceived contamination risks to groundwater from
fracking seem to come from a misunderstanding of the subsurface, and how fracking actually works. Many O&G wells are in fact not hydraulically fractured. If the
rock in contact with the wellbore is permeable enough to flow economical amounts
of hydrocarbons, the well is completed and produced without fracking. These are
known as “conventional” wells. Some oil and gas bearing rocks need a little help,
however. Hydraulic fracturing is used in these wells to create cracks into the formation and stimulate production. These cracks provide an easier flowpath for hydrocarbons to get out of the rock and flow into the well. High-volume hydraulic
fracturing (HVHF) is used on very low permeability rocks like shale to create
numerous cracks deep into the formation to allow for economical rates of O&G
production. Formations that require fracking to produce are called
“unconventional.”
The fracking operation is described in detail in the next chapter, but for the sake
of this discussion, a liquid filling a well (usually water) is placed under pressure
until the rock cracks. It may seem like a fantastic amount of pressure is required, but
it’s actually not that great. Rocks are not as strong as most people think, especially
when being pulled apart. The fracture grows out away from the wellbore to a distance of about 1000 feet (300 m). The height and length of the fracture are carefully
controlled for several reasons. Extending a fracture too far will prevent the proppant
material (sand) from traversing the length of the crack, and the opening will simply
close back up as soon as the pressure is released. Also, fracking “out of zone” into
overlying or underlying non-productive rock layers is a waste of both materials and
the client’s money. Word gets around quickly in the oil fields, and a hydraulic fracture operator who is not capable of keeping the fracture within the productive rock
units won’t be in business for long.
An early assessment of the environmental concerns being raised on the HVHF
process used on gas shales revealed that some of the perceived risks were being
treated as actual risks, while many of the actual risks were being ignored (Soeder
and Kappel 2009). One of the most significant of these perceived risks was that
1 Introduction
evidence is called religion, not science. Pop culture and social media tend to treat all
viewpoints as valid, but considering an idea like the flat Earth to be a valid alternative viewpoint when it is based on zero evidence only ends up overshadowing many
of the real scientific problems in the world. An anti-science response to issues like
climate change, plastic in the oceans, loss of tropical rainforest, spread of contagious disease, the extinction of species, and yes, even fracking with policies based
on beliefs rather than data can have serious consequences. At best, the very existence of the problem is denied, and nothing gets done. At worst, governments and
regulators may focus on fixing the wrong thing and people die from disasters or
diseases.
1.2 Perceptions of Risk
Many of the concerns about the perceived contamination risks to groundwater from
fracking seem to come from a misunderstanding of the subsurface, and how fracking actually works. Many O&G wells are in fact not hydraulically fractured. If the
rock in contact with the wellbore is permeable enough to flow economical amounts
of hydrocarbons, the well is completed and produced without fracking. These are
known as “conventional” wells. Some oil and gas bearing rocks need a little help,
however. Hydraulic fracturing is used in these wells to create cracks into the formation and stimulate production. These cracks provide an easier flowpath for hydrocarbons to get out of the rock and flow into the well. High-volume hydraulic
fracturing (HVHF) is used on very low permeability rocks like shale to create
numerous cracks deep into the formation to allow for economical rates of O&G
production. Formations that require fracking to produce are called
“unconventional.”
The fracking operation is described in detail in the next chapter, but for the sake
of this discussion, a liquid filling a well (usually water) is placed under pressure
until the rock cracks. It may seem like a fantastic amount of pressure is required, but
it’s actually not that great. Rocks are not as strong as most people think, especially
when being pulled apart. The fracture grows out away from the wellbore to a distance of about 1000 feet (300 m). The height and length of the fracture are carefully
controlled for several reasons. Extending a fracture too far will prevent the proppant
material (sand) from traversing the length of the crack, and the opening will simply
close back up as soon as the pressure is released. Also, fracking “out of zone” into
overlying or underlying non-productive rock layers is a waste of both materials and
the client’s money. Word gets around quickly in the oil fields, and a hydraulic fracture operator who is not capable of keeping the fracture within the productive rock
units won’t be in business for long.
An early assessment of the environmental concerns being raised on the HVHF
process used on gas shales revealed that some of the perceived risks were being
treated as actual risks, while many of the actual risks were being ignored (Soeder
and Kappel 2009). One of the most significant of these perceived risks was that
1 Introduction