Schnepp and Moule, JJ. (dissenting).We dissent and agree with Special Term that the arbitrator usurped the school board’s responsibility to deter*919mine a teacher’s tenure and that the board’s decision not to grant tenure did not violate a supplemental procedural step contained in the collective bargaining agreement between the district and the faculty association (see Matter of Candor Cent. School Dist. [Candor Teachers Assn.], 42 NY2d 266; Matter of Cohoes City School Dist. v Cohoes Teachers Assn., 40 NY2d 774). Although Special Term erroneously found that the arbitrator impermissibly determined the existence of an arbitrable controversy, contrary to our previous determination (Matter of Acting Supt. of Schools of Liverpool Cent. School Dist. [United Liverpool Faculty Assn.], 53 AD2d 239, mot for lv to app den 40 NY2d 804), the arbitration award should be vacated because the arbitrator irrationally determined that the school district violated the tenure recommendation report and supervisory report provisions of the agreement (see Rochester City School Dist. v Rochester Teachers Assn., 41 NY2d 578). The contract requires the filing of "Supervisory Reports” for probationary teachers on or before February 1 and June 1 of each year based on no less than two firsthand classroom observations. These reports are required to be "reasonably comprehensive in nature”, based on "classroom observations as well as the teacher’s general performance”, and should point out "strengths and weaknesses, if any, and if necessary, offer suggestions for improvement”. The contract also requires the submission of a "Tenure or Reappointment Recommendations Report” which "shall reflect the overall performance of the teacher” and "unless there are extenuating circumstances, the statements should be consistent with those contained in * * * Supervisory Reports”. In accordance with the contract, on February 10, 1975 the school principal submitted a tenure recommendation report for Ms. Schwab, a teacher in her final probationary year. On May 16, 1975 an incident occurred between the principal and Ms. Schwab. The sixth and final supervisory report for this teacher was submitted by the principal on May 21, 1975. On approximately May 19, 1975 and thereafter the principal made oral and written statements to school authorities which did not recommend Ms. Schwab for tenure. Following this, the school superintendent determined not to recommend to the school board that she be granted tenure. Although the arbitrator found that two classroom observations were made, he concluded that the final supervisory report submitted on May 21, 1975 "did not satisfy the contractual requirements as to content”, that the tenure recommendation of the principal and the superintendent of schools failed to reflect Ms. Schwab’s "overall performance, and * * * was obviously inconsistent with the classroom observations and the Supervisory Reports taken as a whole”, and that there existed no "extenuating circumstances”, all contrary to and in violation of the contract. The arbitrator’s finding that the sixth supervisory report did not satisfy the contractual requirements "as to content”, in that the comments were untimely or inaccurate, were submitted to justify the principal’s ultimate decision not to recommend the teacher for tenure, and did not offer "suggestions for improvement”, was irrational. A fair reading of this report reflects that it was clearly based on the principal’s classroom observations of Ms. Schwab, pointed out strengths and weaknesses, and indicated areas of improvement—all as required by the contract. The arbitrator criticized its contents because weaknesses pointed out in the final report refer to events which occurred prior to, but are not mentioned in, earlier supervisory reports or the earlier tenure recommendation. However, the contract does not require that the content of each report be limited exclusively to events occurring during any specific time frame. Moreover, he improperly determined a question of credibility respecting a statement in the report. The power of the arbitrator is limited to interpret*920ing the contract provisions and determining whether the district violated the contract. The failure to offer "suggestions for improvements” is inconsequential. This was the final supervisory report of a three-year probationary term; with the failure to grant Ms. Schwab tenure, her relationship with the school district terminated. No time remained before the determination of her tenure for her to remedy any deficiency or to improve her performance (see Board of Educ. v Chautauqua Cent. School Teachers Assn., 41 AD2d 47). It would have been an empty gesture to offer suggestions of improvement just prior to the denial of teacher tenure. The arbitrator’s conclusion that the principal’s negative recommendations concerning Ms. Schwab’s tenure made after May 16, 1975, coupled with the superintendent’s failure to recommend tenure for Ms. Schwab, violated the contract was also irrational. The arbitrator found that this action failed to reflect Ms. Schwab’s over-all performance and was inconsistent with the supervisory reports without the existence of "extenuating circumstances”. Thus he irrationally measured the principal’s comments and the superintendent’s conduct by the standards required in the contract for the tenure recommendation report which had been previously submitted by the principal to the superintendent. Further, in concluding that the superintendent failed to comply with these contractual requirements the arbitrator erroneously assigned to the superintendent responsibilities ascribed by the contract to the principal only. Finally, contrary to the finding of the arbitrator, there is no contract provision that requires the superintendent to pursue any investigative procedure before making his recommendation. We conclude that the arbitrator unlawfully augmented the structured evaluation procedures detailed in the contract and invaded the substantive authority of the school board to terminate the employment of a nontenured teacher at the end of the probationary period (Matter of Cohoes City School Dist. v Cohoes Teachers Assn., supra; see, also, Matter of Anderson v Board of Educ., 38 NY2d 897; Education Law, § 3012, subd 2). (Appeal from order of Onondaga Supreme Court—vacate arbitrator’s award.) Present—Cardamone, J. P., Schnepp, Callahan, Witmer and Moule, JJ. [94 Misc 2d 459.]