The Wyoming company whose pipeline leaked 30,000 gallons of crude oil into the Yellowstone River in Montana and its sister company have had multiple pipeline spills and federal fines levied against them in the last decade, according to government records.

Bridger Pipeline, the operator of the Poplar Pipeline that broke recently near Glendive, Montana, recorded nine pipeline incidents between 2006 and 2014, according to the pipeline administration. Combined, the spills leaked nearly 11,000 gallons of crude.

Bridger’s sister company, Belle Fourche Pipeline, recorded 21 incidents over the same period, during which a total of 272,832 gallons of oil was spilled.

Both companies are operated from the same control room in Casper and are owned by the True family. Tad True, vice-president of Bridger and Belle Fourche, said the companies have made great efforts to improve their compliance record. Since 2009, Bridger has been inspected eight times. Belle Fourche has been inspected on nine occasions. The companies have not been issued a fine in any of those inspections, federal records show.

“In this day and age, there is nothing more important than the integrity and safety of our pipes,” True told the Casper Star-Tribune. “We do work very hard to remediate any of those spills and learn from them.”

The Pipeline and Hazardous Materials Safety Administration initially proposed fining the company $70,000 for a series of procedural violations stemming from a 2006 spill, where 210 gallons of oil were leaked. One charge stated Bridger failed to conduct a post-accident review of employees’ activities during the incident.

“In general, Bridger has a poor compliance history,” Jeffrey Wiese, a federal regulator charged with overseeing pipeline safety, wrote in a 2012 order regarding a 2006 oil spill.

The company contended the fines should be reduced, in part, because of its safety record. Regulators rejected that argument.

Wiese wrote that Bridger’s failure to conduct a post-accident review was a missed opportunity to learn from mistakes and prevent them.

Bridger contested the charges, all of which were dropped except the post-accident review violation. Last year, the pipeline administration issued Bridger a final fine of $45,000.

Bridger’s incident rate was 0.028 incidents per mile between 2006 and 2013, or nearly double the industry average, said Rebecca Craven, programme director for the Pipeline Safety Trust, a Bellingham, Washington-based watchdog group. Companies belonging to the Association of Oil Pipelines reported a rate of 0.015 per mile over that time.

The safety trust did not calculate the incident rate for True’s Belle Fourche pipeline.

Federal regulators inspected Bridger operations 38 times between 2006 and 2012, and a new inspection of the company had begun just before the 12-inch line broke on 17 January after a section of the buried line became exposed beneath the river. The line had been buried 8ft below the riverbed when it was last inspected in 2011.

An investigation into the cause of the break is ongoing.

Bridger plans to bury the pipeline deeper under the river.

True said the pipeline industry has made improvement in recent years, though further work is needed. Pipelines nonetheless remain the safest way to transport oil, he said.

“As an industry, we do have a zero incident tolerance. We do take this very seriously,” True said. “The safety of our pipeline and the safety of the people around it are of the utmost importance to us.”