Containment booms surrounding a flooded oil well near the confluence of the Missouri and Yellowstone rivers appear to be holding back oil that leaked from a tank from flowing into the rivers, the North Dakota Department of Health said Saturday.
Crews used two boats to deploy about 6,200 feet of absorbent booms Friday evening to contain oil from a well site owned by Zavanna that had breached the dike.
“They believe they got all the oil contained,” said Kris Roberts, environmental response team leader with the Health Department’s Division of Water Quality.
The oil leaked from a tank that had floated and piping attached to the tank broke, causing oil to spill and breach the dike, said Travis Pfaff, production manager for Zavanna. The oil did not reach the actual river channel, Pfaff said.
The tank contained an estimated 33 barrels of oil, or 1,386 gallons, but crews don’t believe that entire amount released, Roberts said. “We’re pretty certain it was a lot less than that,” Roberts said.
Pfaff said the tank still has a volume of oil in it, but they haven’t been able to determine how much. Another tank at that same location tipped over but did not spill, Pfaff said.
Zavanna, with headquarters in Denver, has three cleanup crews working in the area, coordinated by a production supervisor who works in Williston, Pfaff said.
Crews have surrounded three additional wells with absorbent booms as a precaution, and none had released oil past their dikes as of Saturday afternoon, Pfaff said.
One of the flooded wells had booms surrounding it because it still has a workover rig on the location.
Crews didn’t have time to remove it because they focused on removing chemicals from the well locations, Pfaff said.
“When the ice jam came in, it flooded the area within a couple of hours,” Pfaff said. “The timing just ran out on us and we couldn’t operate in the middle of the night.”
Zavanna crews began securing wells and taking precautions at 10 p.m. Wednesday, Pfaff said.
Lynn Helms, director of the state Department of Mineral Resources, said his office issued a warning several days earlier to owners of about 50 wells in the area that ice jams downstream were causing flooding. Operators received word to shut down the wells and secure their tanks to prevent them from floating, Helms said.
“They were told well before the 12th that there were problems coming,” Helms said.
A Zavanna crew suffered mechanical issues on their boat and ended up stranded Friday, which hindered some of their efforts, Pfaff said. One of the crew members was there for seven hours, he said.
“It became a safety issue, trying to get our individuals safely out of the area,” Pfaff said.
Roberts said he noticed other wells during his aerial tour Friday that had equipment on site, including a Bobcat and sensitive electronic equipment, that crews didn’t have time to remove.
“Water levels come up very, very quickly. You can’t take your time. Some crews got caught,” Roberts said.
The Missouri River at Williston was at just under 26 feet late Saturday afternoon, which is considered major flood stage, the National Weather Service said.
After Monday, the river was going to start trending down, said meteorologist Bill Abeling with the weather service in Bismarck.
However, ice on the Yellowstone or Missouri rivers could create ice jams and cause fluctuations that are difficult to forecast, Abeling said.
During the aerial tour Friday, state officials counted 38 oil wells that have potential for flooding and nine that ended up inundated with water, the Health Department said.
Savanna crews continue to monitor 12 wells in the area, Pfaff said. As waters recede, they will remove any remaining chemicals or crude oil from the well sites, he said.
As a result of the flooding, Savanna officials are considering shutting down the wells during certain times of year, Pfaff said.