July 12 (Reuters) - U.S. energy regulators on Wednesday gave Energy Transfer Partners LP a list of tasks to complete before the Rover natural gas pipeline can enter service.
The $4.2 billion Rover project from Pennsylvania to Ontario is the biggest gas pipeline under construction in the United States.
ETP has long said it expects the first phase of Rover to enter service in late July with the second phase by Nov. 1.
Several energy analysts, however, have said an order by the U.S. Federal Energy Regulatory Commission (FERC) on May 10 banning ETP from new horizontal directional drilling under waterways and roads after a spill in Ohio could cause delays.
ETP spilled about two million gallons of drilling fluid, a clay and water mix, into Tuscarawas River wetlands in Ohio in April.
FERC said in a letter it will continue to ban ETP from new horizontal drilling until it gains "at least a preliminary understanding of the underlying causes for the presence of petroleum hydrocarbons" in the fluid that spilled into the Tuscarawas wetlands.
FERC said it did not approve the use of hydrocarbons in the drilling fluid for Rover.
"I am concerned that the lack of availability of Rover's personnel and its contractors' personnel is delaying our ability to determine the relevant facts," Terry Turpin, director of FERC's Office of Energy Projects said in the letter.
FERC also said a third party contractor helping the commission put together a plan to prevent further inadvertent releases was still working on that plan.
In addition, FERC wants ETP to develop a remediation plan for the Tuscarawas River wetland and remove and dispose of drilling fluids to a site approved of by Ohio's environmental regulators, among other things.
Earlier this week, the Ohio Environmental Protection Agency asked the state's attorney general to pursue civil penalties against ETP for environmental violations during the Rover construction.
Once it enters service, the pipeline will move up to 3.25 billion cubic feet per day of gas from the Marcellus and Utica shale fields in Pennsylvania, Ohio and West Virginia to customers in Ohio, Michigan, Ontario and elsewhere.
One bcf of gas is enough to power about 5 million U.S. homes.
Analysts expect several energy companies to increase gas production once Rover enters service to fill the pipe, including Antero Resources Corp, Eclipse Resources Corp, EQT Corp, Gulfport Energy Corp, Rice Energy Inc , Range Resources Corp and Southwestern Energy Co. (Reporting by Scott DiSavino; Editing by Marguerita Choy)