The National Labor Relations Board has ordered Station Casinos to begin bargaining with the Culinary Union more than a year after workers at its Green Valley Ranch property voted to unionize.

In an order released on Monday, the board found that Station Casinos engaged in unfair labor practices by failing to begin collective bargaining after the Culinary Union was certified in March as the official representative of roughly 890 workers at Green Valley Ranch, including cooks, service workers and housekeepers. Seventy-eight percent of workers voted to join the Culinary Union in an election held in November 2017.

The board said in the order that Station Casinos acknowledged its “refusal to bargain” with the union but continued to assert that the election was not valid and that the union “engaged in objectionable conduct.”

Last year, the company filed a complaint with the board alleging that union representatives interfered with employees’ rights to not vote, intimidated and coerced employees, “destroyed” the secret nature of the vote and monitored employees to determine whether they had voted. The board said in July that the company had failed to prove that the union could have “reasonably tended to interfere with employees’ free choice in the election.”

In the Monday order, the board said that the company has not offered any newly discovered or previously unavailable evidence or alleged any special circumstances that would require it to reevaluate its decision.

“We therefore find that the Respondent has not raised any representation issue that is properly litigable in this unfair labor practice proceeding,” the board wrote.

The board ordered Station Casinos to recognize the Culinary Union as the employees’ representative and collectively bargain with them when requested. The board also is requiring the company to post notices around the property stating that the company “will not fail and refuse to recognize and bargain with [the Culinary Union] as the exclusive collective-bargaining representative of our employees in the bargaining unit” and that it would not “interfere with, restrain, or coerce” employees in exercising their rights to unionize.

A spokeswoman for Station Casinos did not respond to an email Thursday morning asking whether the company intends to begin collectively bargaining with the union.

In a statement, the Culinary Union’s secretary-treasurer Geoconda Arguello-Kline urged the company “to recognize their workers’ voices and votes at Green Valley Ranch and begin contract negotiations in good faith immediately.”

A separate National Labor Relations Board case relating to the Palms unionization election, held in April, is ongoing.