The Pennsylvania Public Utility Commission on Thursday ratified an emergency order authorized on March 7 halting operations on  Sunoco Pipeline's Mariner East 1 pipeline after sinkholes developed along the pipeline route in Chester County.

The PUC's unanimous vote, taken without discussion, orders Sunoco, a subsidiary of Energy Transfer Partners LP, to suspend pipeline operations until additional testing and analysis can take place. The emergency order estimated the pipeline would stay out of service for about two weeks to around Mar. 21.

Gladys M. Brown, the PUC's chair, granted the emergency order after PUC investigators said the sinkholes "could have catastrophic results" if not repaired. The 8-inch-diameter pipeline, which went into service in 1931 originally to transport motor fuel, now carries up to 70,000 barrels a day of high-pressure volatile natural gas liquids such as propane from the Marcellus Shale gas region to a Sunoco terminal in Marcus Hook.

The order does not affect Sunoco's ongoing work to construct the larger Mariner East 2 pipeline adjacent to the first pipeline. That project has aroused strong opposition from residents and environmentalists.