The U.S. Environmental Protection Agency said it didn't detect any harmful air pollutants related to the Exxon Mobil oil spill in Montana.
Around 1,000 barrels of oil spilled into the Yellowstone River, currently at flood stage, late Friday from Exxon Mobil's 12-inch Silvertip pipeline near Billings, Mont.
Exxon Mobil said abatement efforts were hampered by flood waters in the region, though hundreds of people were on scene in an effort to contain the spill.
The EPA said air monitors detected no levels of volatile organic compounds, hydrogen sulfide or benzene from the region.
"We are deploying additional air samplers at specific locations to ensure the continued protection of the community and emergency responders," the agency said in a statement.
Exxon in a statement said there were no reports of negative impact on water quality.
"Active recovery continues in the zones closest to the spill site but we will go as far downstream as necessary to fully understand what areas are impacted," Gary Pruessing, president of Exxon Mobil Pipeline Co., said in a statement.
Exxon under the terms of a corrective action issued by the U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration is required to rebury the pipeline to protect it from external damage and submit a restart plan to regulators before resuming services.