The plaintiffs, suing in their own behalf and as representatives of the Assistant Principals Association, filed an application under G. L. c. 150C, § 10, inserted by St. 1959, c. 546, § 1, to confirm an arbitration award rendered pursuant to a collective bargaining agreement, and the defendant school committee filed a bill for a declaratory decree and for *808vacation of the award under § 11 of the same statute. A judge of the Superior Court denied the application to confirm without acting on the bill to vacate. This was error. When “grounds are urged for vacating . . . the award,” § 10 requires that the court “proceed as provided in sections eleven and twelve.” Under § 11 the judge either vacates the award or denies the application to vacate and then confirms the award. This means that the two proceedings must be consolidated and heard together. Cf. Sheahan v. School Comm. of Worcester, 359 Mass. 702, 711 (1971). The order appealed from is reversed and the case is remanded to the Superior Court for further proceedings consistent with this opinion.

So ordered.