Part 1 of 3 Parts
Researchers at Duke University have released a new report which was published in Environmental Science & Technology. The report found that thousands of oil and gas industry wastewater spills in North Dakota have resulted in “widespread” contamination including radioactive materials, heavy metals and corrosive salts. This contamination poses a very serious threat to public health and the environment.
Testing near the sites of wastewater spills shows that some rivers and streams in North Dakota currently contain levels of these contaminants that rise above the federal drinking water standards. Many cities and towns in North Dakota draw their drinking water from contaminated sources. Federal law mandates that drinking water be treated to remove contaminants. The researchers did not test the quality of tap water in affected cities.
High levels of lead and the radioactive element radium have been found near spill sites. Selenium in some of the water in North Dakota was more than thirty-five times higher than the federal thresholds that apply to fish, mussels and other wildlife. People eat many of these.
Contamination was found on land in addition to that found in water. High levels of radium were discovered in ground downstream from the original location of the spills. There were significant amounts of radium in soil that was further from the spill origin. This research shows that radioactive materials were soaking into the ground and concentrations in the soil were building up as the spills flowed over the ground.
The total number of spills in the past few years is surprisingly high. The Duke researchers mapped out almost four thousand accidental spills of oil and gas wastewater in North Dakota. At the oldest spill site that was tested, contamination remained. About three hundred barrels of wastewater were released four years before the samples were taken and tested. This indicates that any attempts at remediation of that spill site were not sufficient to remove the contamination.
Nancy Lauer is a Duke University PhD student who was the lead author on the report. She said, “Unlike spilled oil, which starts to break down in soil, these spilled brines consist of inorganic chemicals, metals and salts that are resistant to biodegradation. They don't go away; they stay. This has created a legacy of radioactivity at spill sites.”
The greatest concentration of radium found by the researchers measured over four thousand six hundred Bequerels per kilogram. This is more than two and one half times the level of radium found at a spill site in Pennsylvania which attracted national attention when it was discovered. North Dakota law states that waste that is more than one hundred and eighty-five Bequerels per kilogram is too radioactive to dump in regular landfills unless the dumper has a special permit. Such waste cannot even be transported over North Dakota roads without a special state license. The researched concluded that the radioactive contamination found in North Dakota will be present for thousands of years unless extraordinary efforts are made to clear it up.
In their conclusion, the researchers said that “The results of this study indicate that the water contamination from brine spills is remarkably persistent in the environment, resulting in elevated levels of salts and trace elements that can be preserved in spill sites for at least months to years. The relatively long half-life of [Radium 226] (∼1600 years) suggests that [Radium] contamination in spill sites will remain for thousands of years.”
Please read Part 2