By Patrick Rucker

(Reuters) – Cynthia Quarterman, the federal regulator who oversaw expansion of the U.S. oil train sector and the fallout from several fiery derailments, will step down, two sources familiar with her intentions said on Wednesday.

As administrator of the Pipeline and Hazardous Materials Safety Administration (PHMSA) since November 2009, Quarterman has been a leading safety official as oil train deliveries from North Dakota neared 750,000 barrels a day and spectacular derailments in the United States and Canada raised concerns about such shipments.

PHMSA, an agency within the U.S. Department of Transportation, has been under scrutiny for more than a year as officials have tried to respond to the hazards posed by oil train cargoes, which have grown in volume along with a rise in domestic crude production.

PHMSA did not confirm Quarterman’s departure, which reportedly will come next week.

Quarterman, previously an attorney whose practice focused on the transportation and energy industries, was often the face of federal policy, defending government actions to lawmakers, industry and safety advocates.

“If you have upset everyone a little, you’re probably doing a good job,” said Brigham McCown, a former PHMSA head.

“The prevailing view is she’s done a good job in challenging times,” McCown said.

Among other things PHMSA has been tasked with writing new safety standards for oil trains and other hazardous cargo. Tuesday marks a deadline for public comment on the proposed safety rules.