Oil and water won’t mix on Oologah Lake if a pipeline repair goes as planned.
Enbridge Energy Co. is performing maintenance on an underwater oil pipeline that was in place before there was an Oologah Lake. The pipeline was built in 1949 and the lake was formed in 1963.
The Ozark Pipeline carries 200,000 barrels of light crude oil daily from Cushin to Wood River, Ill.
Before starting the maintenance work, Enbridge cleared the oil from the pipeline and then flushed it with nitrogen. Once the pipeline was clear, the valves on both sides of the lake were closed.
“It has been purged. That line is isolated and it’s empty,” said Enbridge project manager Corey Dahlin. “We’ve taken every precaution we could think of.”
The pipeline was shut down after a routine inspection of the line using a device called a “smart pig” uncovered a possible problem.
A recent “smart pig” report detected a feature that required further inspection. Enbridge is checking a 40-foot section of the 8,000-foot pipeline that runs under the lake.
Dahlin said, “We realize the importance of the integrity of this line. The goal is zero leaks. We’re trying to be proactive, not reactive.”
A barge has been anchored above the work area.
“The visibility is very low. They’re doing a lot of work by feel but they’re very experienced divers,” Dahlin said.
Enbridge tests water quality near the work area on a daily basis. So far, no oil has been present in the water.
“We’ve had no evidence of any kind of leak,” Dahlin said.
Once the divers uncover and inspect the pipeline they will report to engineers who will determine the maintenance needs and develop a plan. A minor crack in the line can be repaired.
Dahlin said the worst case scenario would be replacing a section of the pipeline. That would require building piers around the pipe to block off the lake water.