Filter socks have been a major part of North Dakota’s energy industry news since its most recent oil boom. Abandoned truck beds were found a few weeks ago filled with filter socks outside of Watford City. Last year during an EPA inspection there was another deserted truck bed found on the Fort Berthold Indian Reservation with radioactive filter socks on it. Just this past week a massive amount of filter socks (5 times more than was on the truck beds outside of Watford City) were found tucked away in an old gas station in the small town of Noonan, ND. Each story mentions their potential radioactivity, but hardly ever goes into detail about what they are used for, why they are radioactive, or how this could potentially affect citizens of the surrounding areas.
What are filter socks?
Filter socks, sometimes referred to as ‘oil socks’ are pretty simple in definition. They are large, sock-like bags that are used to capture silica dust during the fracking process. During the drilling process, a lot of the wastewater used to break apart the shale deep beneath the earth comes back up to the rig. Oil socks filter out the solids that come up with it. Wastewater needs to be treated and cleaned after a drill operation because it contains chemical additives, and the flow back water contains elements found in the shale. The wastewater may include high levels of salt, metals, organic compounds, and naturally occurring radioactive material (NORM).
Why are they radioactive?
Each filter sock has a range of 5-80 picocuries per filter. Picocuries are the unit used to measure the intensity of radioactivity in an item. Each curie represents around one gram of radium, the primary radioactive component found in wastewater during the drilling process. Radium needs to be inhaled, ingested, or airborne to affect human beings. Several dozen tons of filter socks are used every day in North Dakota alone. There is nowhere to properly dispose of them in the state, and they are usually sent in bulk to radioactive disposal sites in Colorado. JMAC resources handles most of the solid waste disposal in the oil fields, and it is around 35-50 dollars to dispose of a barrel of solid oilfield waste. Around 75 tons of solid oilfield waste is created every day from all of the rigs in North Dakota. One-third of that waste is considered radioactive.
How does/could this affect the surrounding areas?
Since radium needs to be inhaled or ingested to affect human beings, it has the means to affect people if they make direct contact. It has the potential to cause cancer or other disorders because it emits alpha particles when it decays, and those particles kill and mutate cells in the human body. Radium is also chemically similar to calcium, so it has the potential to replace calcium in bones. If disposed of correctly, the filter socks would have little impact on citizens not working in the oil industry. However, there seems to be an influx of situations where filter socks containing the radioactive material are being left in various places where people could potentially come into contact with them. For example, in 2013 The Three Affiliated Tribes’ environmental division was concerned about children playing with abandoned filter socks on the reservation, because they closely resemble small nets. Many socks have been found in city dumpsters in Williston, which presents a danger to the citizens of the city. The varying radioactivity levels of each filter sock makes it hard to determine how many of them are too dangerous for human contact, but a large amount of them are moderately- heavily radioactive.
The disposal issues that North Dakota faces in dealing with these oil socks has been plaguing the state’s oil industry and its citizens for over a year. Many of these problems could be remedied if there was a system in place that monitored their removal. Currently there are large Geiger counters at local landfills that catch people trying to transport the filters into them. If a filter sock is found in a load attempting to get into the landfill, there is a $1,000 fine per sock. Most of the time it is unknown what happens to the socks after the fine is administered, and there is currently no way to track the waste within the state. The oil industry is fantastic for the economy and has benefited the state in many ways however, the speed that the industry has grown has caused regulation of oil waste to take a backseat to the production.