(1) Every Committee of Arbitration shall consist of five members, namely:--
         (a) a Chairman who shall be a person not in the service of the Government or the Board, and who shall be nominated by the Officer Commanding the Station;
         (b) two persons nominated by the Board;
         (c) two persons nominated by the other party concerned.
     (2) If the Board or the other party concerned or the Officer Commanding the Station fails within seven days of the date of issue of the notice referred to in section 326 to make any nomination which it or he is entitled to make or if any member who has been so nominated neglects or refuses to act and the Board or other person by whom such member was nominated fails to nominate another member in his place within seven days from the date on which it or he may be called upon to do so by the District Magistrate, the District Magistrate shall forthwith appoint a member or members, as the case may be, to fill the vacancy or vacancies.