Elevated levels of radium show up near oil rigs in the Gulf of Mexico, according to Eckerd College student
During the oil extraction process, radium is released through what's called "produced water" – it’s the water that comes up with a mixture of oil when the rigs pump.
After a research excursion with the "Scientist at Sea" program back in May, an Eckerd College student has released results showing elevated amounts of radium near oil rigs in the Gulf of Mexico.
When sediment gets stirred up, like at river mouths, the activity releases radium, which is a naturally occurring radioactive metal.
During the oil extraction process, radium is released through what's called "produced water" – it’s the water that comes up with a mixture of oil when the rigs pump. It mixes with sediments that have been stored for thousands of years in the Gulf floor.
Silje van Mierlo, a junior at Eckerd, said radium can be used as a tracer for produced water.
"So that sediment is really rich in radium and then when the water mixes with that sediment, it reintroduces radium into the water column, which then gets released into our waters," she said.
Van Mierlo discovered that the radium content was actually higher in deep areas of the Gulf near oil rigs than near river mouths.
“If you're closer to a river mouth, there's more water activity, and more resuspension between water and sediment, so there'll be a higher radium activity,” she said. “But if you're out in the deep ocean, there's less water activity and resuspension at the bottom of the ocean because there's not much going on there, so technically, there should be a lower radium activity … further out in the ocean away from rivers.”
Her project received the Presidential Award during the Scientist at Sea Symposium in November.
“I have been working really hard on this project and I really like it, but I didn't expect to actually be getting an award for it,” she said. “But it felt very good to see that people understood what I was researching, and they saw the importance of it.”
She plans to continue her radium research until she graduates with her bachelor’s degree in 2024, and would eventually like to update a 40-year-old data set documenting how much radium is coming from produced water.
"Within 40 years, especially in the Gulf of Mexico, there's been a huge increase in oil variants, so I don't believe that that radium activity that was measured 40 years ago is representable, of what it's like today," she said.
“Then based on that … if it's really a big, major contributor to a radium content, I would love for there to be a bigger restriction on how to minimize how much radium has been released.”