A carnival company must pay more than $383,000 in back pay after it forced a union on immigrant workers and struck a collective bargaining agreement that paid the employees lower wages than they would have received otherwise, the National Labor Relations Board has ruled. The order the unanimous board issued on Tuesday granted summary judgment to the NLRB general counsel’s office in a dispute over how much back pay Swyear Amusements owed under a settlement in which the carnival admitted to unlawfully recognizing the Association of Mobile Entertainment Workers as the representative of employees working under H-2B visas. The back pay will go to 41 workers and will include additional interest, according to the decision.