A Slope County woman who worked as a dispatcher for an oil field equipment and transportation company says she's owed money for more than 6,000 hours of overtime.

Noreda Mann of Marmarth is asking for more than $350,000 in a federal lawsuit against Hamm & Phillips Service Co., Inc., an Oklahoma-based business that also serves North Dakota, South Dakota, Montana, Kansas and Texas.

Mann's lawsuit accuses the company of refusing to pay her for 6,323 hours of overtime in a 19-month period between February 2006 and September 2007. That's an average of 123 working hours per seven-day week and 171/2 working hours per day.

Teresa Burnett, a spokeswoman for Hamm & Phillips, said she could not comment on details of the case, but said the company "is confident in its position and hopes to obtain a speedy dismissal" of the lawsuit.

"The only plaintiff in this lawsuit is a former, not a current, employee," Burnett said in a statement. "The lawsuit contains allegations that are clearly without merit, and the company denies any violation of federal labor law."

Mann and her attorney, Paul Ebeltoft of Dickinson, did not return phone messages seeking comment on the lawsuit.

Mann worked for Hamm & Phillips from Feb. 6, 2006, to Sept. 1, 2007. Her lawsuit describes her work as a dispatcher as being "directly essential to maintaining communication with crews, receiving maintenance calls, and tracking crew location, job status and crew needs" for workers in North Dakota and other states.

Mann claims she was required to be near the dispatch radio booth after regular working hours when she was at home in Marmarth, a town of about 140 people near the Montana border. "This requirement made it impossible for (Mann) to leave the immediate vicinity of the radio when she was supposed to be off work and was not being paid for her time," her lawsuit says.

Federal labor regulations say that any worker who is required to remain on call "on the employer's premises or so close thereto that he cannot use the time effectively for his own purposes" is working and should be paid.

"An employee who is not required to remain on the employer's premises but is merely required to leave word at his home or with company officials where he may be reached is not working while on call," reads a provision in Title 29 of the federal code.

Rich Kulczewski, a regional spokesman for the U.S. Department of Labor, did not return phone messages seeking comment.

Mann's regularly hourly rate was $17.50 per hour from February 2006 through Oct. 28, 2006, and $19.38 per hour from Oct. 29, 2006, through Sept. 1, 2007. At the overtime rate of 11/2 times the normal rate, she should have received about $175,018, her lawsuit said.

Mann is asking for an additional $175,018 as "liquidated damages."

Lisa Fair McEvers, North Dakota's labor commissioner, said state and federal provisions covering on-call pay are nearly identical.

"We do get calls from time to time, but it's not a real common issue," McEvers said. "Sometimes, there's a way we work it out without doing a formal complaint."