DULUTH — The union that represents snow plow drivers in Minnesota’s St. Louis County has filed a notice to strike with the state if negotiations for a new labor agreement continue to break down.

The Star Tribune reported Thursday that plow drivers and other public works employees could walk out after a 10-day “cooling-off” period after mediation. If mediation fails, the Teamsters Local 320 said in a statement that “county employees are permitted to strike on any future date.” The statement also said that “an internal union process will determine when employees are to begin a work stoppage.

Union members overwhelming voted last month to authorize a strike.

The current contract expired at the end of the year but it will be in effect until a new agreement is reached. The current contract covers 168 employees.

A possible strike comes at a time when Duluth experienced its third-snowiest calendar year on record.

“We remain hopeful that a strike can be averted and a contract agreement will be successfully reached that is fair to our employees and fair to our taxpayers,” St. Louis County spokeswoman Dana Kazel said in a statement.