"The Unified Command continues to monitor and respond to an oil discharge near the Main Pass Oil Gathering (MPOG) company's pipeline system ... Initial engineering calculations indicate potential volume of crude oil that could have been released from the affected pipeline is 1.1 million gallons," the Coast Guard said in a statement.
"The Unified Command is working diligently to determine the source of the release."
According to the statement, the Unified Command conducted multiple overflights on Friday and Saturday, observing visible oil moving southwest from the Louisiana shore and deploying three skimming vessels to recover surface oil.
"On Saturday and Sunday, overflights observed intermittent surface sheens. Additional surface observations are ongoing with two Coast Guard cutters on scene and additional overflights," the statement said.
The vehicles sent last week haven't found the source of the leak yet, but they will keep checking the pipeline if the weather allows, the statement said.
The Coast Guard is overseeing efforts to reduce the impact of the oil discharge, while the Unified Command collaborates with federal, state, and local agencies to ensure public safety, environmental protection, and a comprehensive response to the incident, the statement added.