Where to Put the Hydrofracking Wastewater?
Where to put the hydrofracking wastewater?
by Marla Coppolino, August 11, 2010
With an average of approximately 3 million gallons of hydrofracking solution used per frack, and with an average of 10% of wastewater returning to the surface as flowback wastewater (approximately 300,000 gallons), there is genuine concern in New York state about what will be done with the large amounts of wastewater generated from fracking operations. (See "Water worries: An introduction to some of the water issues associated with shale gas drilling" for information related to this article.)
This wastewater is unique among municipal and most industrial wastewaters, as it contains extremely high levels of salts, technically known as total dissolved solids (TDS). The dissolved solids include substances such as calcium, sodium, magnesium, chlorine, carbonate, and sulfate. The waste water often has TDS concentrations as high as 300,000 parts per million, or five to six times greater than the TDS of seawater. The wastewater contains so many salts due to its passage through rock layers bearing salts that occur between the shale and the ground surface. On its return to the ground surface, the water flushes up the salts, as well as a variety of other solid matter.
Hence, one of the greatest problems with hydrofracking wastewater is that its high salt content can potentially harm terrestrial and freshwater aquatic ecosystems. Even a small amount of salt in freshwater can disrupt an ecosystem. Unable to cope with high salinity levels, freshwater organisms suffer and eventually die. Then, among many problems, the altered habitat allows for invasive organisms that normally thrive in brackish waters to enter the area and flourish. One example of this situation occurred in Pennsylvania's Monongahela River, where golden algae (Prymnesium parvum) invaded and now has a stronghold as the dominant plant in an area adversely affected by fracking wastewater. According to the West Virginia Department of Environmental Protection (WV-DEP), this toxic bloom of algae was linked to a fish kill in Dunkard Creek, a tributary of the Monongahela River (http://www.uppermon.org/Dunkard_Creek/Algae.html).
Naturally occurring radioactive elements are also flushed up in fracking wastewater; Scientific American sources indicate concentrations as high as 267 times greater than the allowable limit for drinking water (http://www.scientificamerican.com/article.cfm?id=marcellus-shale-natural-gas-drilling-radioactive-wastewater).
The issues surrounding wastewater extend to air quality. According to Deborah Goldberg, Northeast Managing Attorney for Earthjustice, even a well-managed, centralized fracking wastewater impoundment can send volatile organic compounds into the air, potentially affecting human health.
Given the issues of high salinity, radioactive elements, and altered air quality, we return to the central question: what are some ways to manage fracking wastewater? We can look to our neighboring Pennsylvania for examples of methods that have or have not been effective means of dealing with this wastewater.
In early stages of gas drilling in Pennsylvania, the fracking wastewater had been dealt with in several ways. Initially, it was treated at sewage treatment plants and diluted, then discharged into the Monongahela River, upstream of the water source of approximately 350,000 people. The problems with this method of wastewater disposal were first noticed not by the general public, but by industries that noticed the total dissolved solids (TDS) levels in their intake were much higher than they should have been, which can cause damage to the industries' processes. The Pennsylvania Department of Environmental Protection (PA DEP) placed restrictions on this way of dealing with wastewater by allowing no more than 10% of a sewage plant's intake to be from hydrofracking wastewater.
Pressures were placed on gas companies to find an alternative, and thus new industrial plants were constructed to process their wastewater. However, permits were issued only if the facility was not discharging its treated water into streams or rivers. The treated water is instead diluted with clean water and sent back to the drilling fields for re-use in other wells.
A third method to deal with Pennsylvania's fracking wastewater came about when gas companies treated the water at the fracking site. The water was contained in pools known as impoundments, and over time the solids would settle and crystallize. One concern was that the ground surfaces of these impoundments were not inspected by the DEP before the linings were placed in. An inspection of the ground by the DEP would ensure that the surface is smooth, free of debris, and would safely support the liner without causing tears in it. The water in impoundments, less saline after being treated at the sites, was then sent through pipes to another fracking site. Some issues developed here when some of the PVC pipes, set over the ground, started leaking. With no regulations to oversee the gas companies' processes to treat their own water and send it to another site, the potential for unrecognized problems became a concern of citizens. Another method was created, called "invisible transportation systems," comprising metal pipes to transport water. They were called "invisible" because they were buried under the ground. This process also lacks regulations.
Finally, another option used by Pennsylvania was simply to transport the wastewater out of the state by truck - mostly to Ohio, and some to West Virginia, where it was handled by injecting it underground, where it would stay.
At present, there remains a dearth of options for wastewater storage and treatment for New York State.
While there are currently no set plans on how to treat wastewater in New York State, some possible options similar to those used in Pennsylvania have been discussed, and these are as follows:
1) Deep well injection. Wastewater is injected into a large well drilled specifically for that purpose, or into an old oil well. This was proposed by one gas company for a town near Keuka Lake. Though the well would be permitted and regulated by the Environmental Protection Agency (EPA), the plan was later abandoned because of citizen concerns related to whether the water had potential to seep into the nearby lake because of being situated in close proximity to it (http://www.fingerlakesmedia.com/news.php?viewStory=1127).
2) Shipping the water out of NYS. There are eleven plants in Pennsylvania and one in Ohio that are considered potential sites to which New York's wastewater could be shipped, but many of these sites are already processing waste water at near capacity levels.
3) Building new treatment plants. Gas companies are investigating the construction of new wastewater treatment plants. This option might represent the best choice if all safety standards are met and seems to hold favor with both community members and industrial representatives.
4) Treatment at municipal plants. This option is not considered to be viable, as existing municipal plants are not able to handle the amount of water, nor are they equipped to deal with industrial wastewater, as was learned in Pennsylvania.
It has been suggested that if gas companies could pre-treat wastewater, removing chemicals most problematic to municipal plants, then wastewater could perhaps be ultimately sent to municipal plants. While this step could eliminate a few of the treatment issues, there would still be excessive overload on the municipal facilities.
6) Wastewater impoundments. Such impounds could potentially contain 16 million gallons and have been discussed as an option in for New York State. An analysis of the plan was performed by a panel of experts that included a petroleum engineer, a toxicologist, a hydrogeologist, and general environmental consulting firms. Collectively, they found the proposed wastewater impoundments to be inadequate in terms of safety.
Perhaps the only general consensus we can reach is that fracking wastewater should be managed in a responsible, tightly regulated way. But can new technologies to manage this particular wastewater be developed in time? As of this writing, the question remains unresolved.