The complaint says the women were denied promotions and raises, subjected to sexist comments, treated more favorably if they had sex with some managers, disciplined more harshly than men and discouraged from complaining about the treatment.
U.S. Mint Director Henrietta Holsman Fore, who oversees all U.S. mints, on Tuesday ordered a search of lockers, toolboxes and other areas of the mint for offensive art and graffiti and ordered a team of managers to come to Denver to meet with employees.
"I take the type of behavior described in these allegations very seriously," she said.
The petition was filed with the U.S. Treasury Department, which operates the mint. It will be assigned to an administrative law judge with the U.S. Equal Employment Opportunity Commission, said Lynn Feiger, the women's attorney.
Feiger welcomed Tuesday's action but said, "We just wish they were willing to do something previously."
Kenneth Boris Sr., industrial manager at the Denver Mint, declined to comment.
The complaint does not seek punitive damages; Feiger said the women want to stop discrimination and are seeking changes in how the mint handles complaints.
Beverly Mandigo Milne, who has worked at the mint since 1978, said women have complained for years to supervisors, managers and union officials. She said some of the women have filed individual complaints with the mint's equal employment opportunity staff.
"There has been unfair treatment to women in promotions, job assignments, training opportunities — there's been such harassment, and it has created an overall hostile work environment," Mandigo Milne said.
Mandigo Milne said the women were told there would be a follow-up after some met in November 2001 with an official overseeing U.S. mints.
"We never heard a word," she said.
The women decided to petition higher authorities and sent their complaint to U.S. Treasury Department headquarters in Washington.
The Denver Mint employs 528 people, 107 of them women.