The U.S. Department of Labor has sued a California residential care provider for gross violations of federal wage and hour regulations after “having exhausted all attempts to reach a settlement,” the department said in a statement.

The lawsuit, against the owners of San Miguel Homes for the Elderly, LLC, which operates three residential care facilities for older adults in Union City, was filed in the U.S. District Court in Northern California. The labor department is seeking to recover back wages and damages it says are owed 22 employees.

The workers at San Miguel Homes for the Elderly, the department maintains, routinely have worked more than 40 hours per week, but they have not been compensated at time and one-half their regular pay rates as required by law. Instead, San Miguel Homes for the Elderly either paid them for eight hours of work per day or paid them a flat daily rate that did not account for all hours worked. “As a result, the workers’ hourly rate has been less than the federal minimum wage,” according to the labor department.

Also, the complaint says, in many work weeks, the facility owners did not keep any records of the hours worked by its employees. In other work weeks, the records kept were not accurate.

“The department’s Wage and Hour Division continues to see problems in the residential care field, particularly in the Bay Area,” according to the labor department. “Earlier this year, the department announced that it had returned more than $6.8 million in overtime and minimum wage back wages and damages to Bay Area residential care workers from 2011 through 2014.”

McKnight’s Senior Living did not receive a response to requests for comment made via phone and email to San Miguel Homes for the Elderly Administrator Precilla San Miguel.