Washington (CNN) The American Federation of Teachers union sued Education Secretary Betsy DeVos Thursday, alleging that the department has mismanaged a federal program that grants teachers and other public service workers loan forgiveness after they make 10 years of payments.

About 1% of the more than 73,000 borrowers who have applied for the Public Service Loan Forgiveness program have been granted relief since the program was created in 2007, according to department data.

The lawsuit blames the Department of Education for denying applicants "on arbitrary and capricious grounds" and failing to put a process in place to review erroneous decisions or ensure loan servicing companies provide accurate guidance to borrowers about their eligibility.

"Instead of helping the millions of Americans owed debt relief under the Public Service Loan Forgiveness program, DeVos has hurt and pauperized them. And instead of working with lawmakers to improve the program that millions of teachers, firefighters, nurses and first responders deserve, DeVos has vandalized it," said Randi Weingarten, president of the American Federation of Teachers, in a statement.

A spokeswoman for the Department of Education declined to comment on pending litigation.

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