Lake contaminated by treated wastewater
The rapid growth of hydraulic fracturing in the US is raising concerns about what to do with the billions of gallons of wastewater produced by the process, a study in ACS’ Environmental Science & Technology journal has highlighted.
Researchers now believe that the current chosen method of treating and releasing the wastewater into surface waters has led to radioactive material and endocrine-disrupting chemicals contaminating a Pennsylvania watershed.
While the use of fracking to extract oil and gas is on the rise in America, resulting in a shift away from coal and helping to reduce greenhouse gas emissions, the process also produces large amounts of wastewater.
This wastewater contains radioactive materials, salts, metals, endocrine-disrupting chemicals and polycyclic aromatic hydrocarbons - which could pose risks to both the environment and human health.
The facilities that collect the wastewater provide only limited treatment before it is released back into surface waters.
To test what impact releasing the wastewater in this fashion might be having on the environment, researchers sampled porewaters and sediments from a lake downstream from two facilities that treat fracking wastewater in Pennsylvania.
Peak concentrations of radium, alkaline earth metals, salts and organic chemicals were all detected in the same sediment layer by the analysis.
Nonylphenol ethoxylates, which are endocrine-disrupting chemicals, and polycyclic aromatic hydrocarbons, which are carcinogens, were the two types of major organic contaminants discovered.
Researchers say that while the risks associated with this contamination are unknown, tighter regulations on wastewater disposal could help to protect both the environment and human health.