BP employees discovered an uncontrolled natural gas leak that was accompanied by the spray of crude oil.
On Saturday night, workers were able to enter the wellhouse and slowly reduce the pressure.
Alaskan and federal officials had identified two leaks spewing methane gas which is linked to climate change.
The volume of the leak had not been determined and the cause of the release was unknown, according to a statement from the state's Department of Environmental Conservation.
The total amount of oil spilled and whether the crude affected the snow-covered tundra nearby isn't yet clear, though authorities have expressed confidence the crude contamination is contained with a gravel area directly surrounding the well site.
The spokesperson Brett Clanton, from BP's official team present there said the crew members used infrared cameras to see the condition of the leakage, which is found to be not that severe. There had been no injuries and no reports of harm to wildlife. BP and other groups were still working on a response plan for the leak on Sunday, according to the report.
The North Slope is home to the biggest legacy conventional oil fields in the United States and has recently seen a revival after energy firms made a decision to try and extend these fields' productive lives and possibly even tap hitherto undiscovered deposits. This leak came due to that only. North Slope production was up to 565,000 barrels a day in March, its highest level since December 2013. This increase is like another sign along with the discoveries of multibillion barrels in the recent months that the North Slope area is on the way to reverse decades of declining volumes and huge investments. Alyeska Pipeline Service Co.is a joint partnership between North Slope's producers Exxon Mobil Corp., BP Plc, and ConocoPhillips.
Alaskan North Slope crude was valued at $1.80/bbl over USA benchmark West Texas Intermediate on Monday, according to data compiled by Bloomberg.