pipe@ (Updates with ETP comments)
Jan 19 (Reuters) - Ohio environmental regulators on Friday asked federal energy regulators to order Energy Transfer Partners LP to cease drilling operations on the Rover natural gas pipeline under the Tuscarawas River over concern about the potential for a spill.
The Ohio Environmental Protection Agency said in a filing with the U.S. Federal Energy Regulatory Commission (FERC) that it learned last week that 146,000 gallons of drilling fluid were "lost down the hole" that ETP is drilling under the Tuscarawas River in Stark County, Ohio.
That is the same site as a spill last April of 2 million gallons of mostly clay and water used to lubricate drilling blades, which led FERC to temporarily ban ETP from new horizontal drilling in May.
"FERC cannot idly stand by and allow these significant threats to Ohio continue," the Ohio EPA said, noting it wants the federal agency to "order the cessation of drilling operations until such time a solution is developed."
Alexis Daniel, a spokeswoman for ETP, in an email said "we are working in coordination with FERC on all of the remaining HDDs (horizontal directional drilling)and are in compliance with the HDD contingency plan that was approved by FERC."
Ohio, which asked FERC to ban all of ETP's horizontal directional drilling in November, said in its filing last week that it wanted more information on the Tuscarawas drilling.
FERC in December allowed ETP to complete all horizontal drills on the Rover project, including those in Ohio.
Pipeline companies use horizontal directional drilling to cross under large obstacles like highways and rivers.
Once finished, the $4.2 billion Rover pipeline will carry up to 3.25 billion cubic feet of gas per day from the Marcellus and Utica shale fields in Pennsylvania, Ohio and West Virginia to the U.S. Midwest and Ontario in Canada.
One billion cubic feet per day of gas can supply about 5 million U.S. homes.
The company said it expects to finish Rover by the end of the first quarter.
"We are more than 76 percent complete with all HDD activity and more than 99 percent complete on all construction activities for the project," Daniel said.
About 1.0 bcfd of gas was already flowing on completed portions of the pipeline, according to Reuters data.
Major gas producers that have signed up to use Rover include units of privately held Ascent Resources LLC, Antero Resources Corp, Range Resources Corp, Southwestern Energy Co, Eclipse Resources Corp and EQT Corp.
(Reporting by Scott DiSavino; Additional reporting by Vijaykumar Vedala in Bengaluru Editing by Richard Chang and Lisa Shumaker)