A leak was reported July 1 on the 12-inch Silvertip oil pipeline near Billings, Mont. Around 1,000 barrels of oil spilled into the Yellowstone River, ExxonMobil said. The company in its initial estimates reported oil spots as far away as 80 miles from the spill.
Flooding along the Yellowstone River hampered preliminary response. The U.S. Environmental Protection Agency said as the flooding recedes, teams would be deployed for cleanup operations.
The EPA said it received a draft plan from Exxon on the Yellowstone cleanup operation. The agency said Exxon's plans for oil recovery containment, source release area and remediation require further clarification.
"The EPA has instructed ExxonMobil to provide a revised plan within the week," the agency said in a statement.
Montana Gov. Brian Schweitzer, in a letter to Exxon, requested three years of data, including viscosity, volatility and toxicity analysis, regarding the type of crude oil sent through Silvertip.