Ethane deliveries on Enterprise Products Partners LP’s (EPD) Appalachia-to-Texas Express (ATEX) pipeline are still limited days after a stretch of the line ruptured and exploded, according to a company representative.

EPD spokesman Rick Rainey said there’s not “really much new to report,” as federal regulators with the U.S. Pipeline and Hazardous Materials Safety Administration (PHMSA) were on site working with company personnel trying to determine what went wrong. Rainey didn’t say when the pipeline, which runs from Washington County, PA to EPD’’s Mont Belvieu, TX, complex, would be fully operational.

“We do not have an estimate yet as to when the line will be returned to service,” he said. “Crews and equipment are standing by and are ready to begin the repair process once we receive regulatory approval to move forward.”

It’s unclear how long PHMSA’s investigation is going to take. The agency issued a corrective action order (CAO) to EPD on Thursday, which restricts the company from operating the affected 26-mile segment until a restart plan is approved. The agency said the pipe failed near a weld.

The incident occurred at about 10:40 a.m. EST Jan. 26 on a 20-inch diameter section of the pipeline in Brooke County, WV (see Daily GPI, Jan. 26). EPD said its controllers detected an abnormal pressure drop at a pump station there and later confirmed a rupture. A fire burned for most of Monday and extinguished itself after emergency responders and EPD were able to cut the flow of ethane.

In its preliminary findings, PHMSA said the rupture led to the loss of 23,901 bbl of ethane and noted that the accident occurred on a 255-mile unit of ATEX that runs from Washington County, PA, to Seymour, IN. The 26-mile segment that failed and remains shut-in by PHMSA’s CAO transports liquid ethane from Greensburg, PA, to West Virginia and runs from MarkWest Energy Partners LP’s processing facility in Houston, PA, to the Ohio River.

The 1,265 mile ATEX is a critical outlet for ethane produced in the Marcellus and Utica shales. The pipeline has four injection points in the region and two were impacted by the blast. Rainey said deliveries are still being made downstream of the rupture.

“Once Enterprise receives approval to restart, the CAO adds an additional restriction in requiring the company to not operate the pipeline above 80% of the pressure it was operating at when it originally failed until PHMSA determines the restriction can be removed without impacting safety,” agency spokesman Damon Hill said.

ATEX entered commercial service in January 2014.The company reported a record gross operating margin of $5.3 billion when it released 4Q2014 earnings Thursday, in part to new projects such as ATEX. EPD said the pipeline, which has a capacity of 125,000 b/d, transported 72,000 b/d in 4Q2014.

PHMSA said the affected 26-mile segment was constructed in November 2013.

The incident has garnered significant attention in the region, where ethane takeaway is somewhat limited already. Fielding an audience question at an industry conference in Pittsburgh on Thursday, Richard Hoffman, executive director of the Interstate Natural Gas Association of America, called the rupture “unfortunate.”

“Everybody is working so hard to make sure that kind of thing doesn’t happen, those accidents are still very infrequent,” Hoffman said. “They certainly can be hazardous and do a lot of damage. And you know, companies are out there all the time testing, doing integrity verification on their pipelines. Under federal law, they’re required to do that, but they’re doing it under their own business practices because nobody wants that to happen. I call accidents like that unfortunate.”