The proliferation of oil wells in North Dakota’s Bakken Shale region has been a 21st Century Gold Rush for energy companies, but all the new oil production is taking a toll on the environment in ways previously unforeseen.
A recent decline in North Dakota’s oil production due to declining oil prices has allowed environmental experts to assess some of the ways Bakken shale development has damaged the environment, most notably the rich prairie soil and underlying aquifers. One of the biggest threats is the industry’s production of brine, which is churned up with oil in the drilling and extraction process.
According to Bloomberg BNA, the salt water comes up to the surface with crude oil in the extraction process. The salty water is then separated from the oil and transported for disposal via pipeline or surface transportation, and it is often spilled.
“Spilled brine can ruin soil chemistry and severely alter groundwater,” Bloomberg BNA explains, and these harmful effects linger much longer than spilled oil, which eventually becomes degraded by bacteria.
Salt, however, remains in the soil and groundwater until diluted or flushed out with fresh water – a process that can take up to 10 years to effectively complete. The most effective remediation for spilled brine is a complete removal of the contaminated soil and groundwater.
This problem is compounded by the nature of the brine from the Bakken shale. This water is 10 times saltier than seawater and three times as saline as the water typically produced in other U.S. oil and gas fields, according to U.S. Geological Survey data.
“The salty water causes clay particles in the soil to swell up enough to squeeze shut the pores that allow water to seep through.” Bloomberg BNA reported. “Brine also reduces the osmotic pressure that helps plants take in water through roots. Both factors mean that plants will die from lack of water in salty soil.”
Max Post van der Burg, a U.S. Geological Survey research ecologist based in Jamestown, N.D., told Bloomberg BNA that there has been an “exponential increase in brine spills” the Bakken region correlating to the explosive growth oil production there in recent years.
Data collected by the University of North Dakota’s Energy & Environmental Research Center shows that in 2014, approximately 71,000 barrels of brine were spilled in 855 incidents associated with oil and gas development in North Dakota – nearly 11.5 times more brine spills than in 2001 when 6,200 barrels were spilled.
The prairie grasslands have also been marred by access roads that connect hundreds of wells and buried pipelines. According to Bloomberg BNA, natural wetlands known as “prairie potholes” exist throughout the region, providing refuge for migratory birds. But many of those have been contaminated with oil and brine spills in recent years.
Source: Bloomberg BNA