Any employee member of the city employees' retirement system may upon application to the pension commission purchase prior service credit for full-time service as a permanent employee of the city which preceded his membership in its pension system. Purchase payments for prior service shall be made at the salary scale and rate of contribution effective at the time such application is made. Time payments and methods of deductions shall be the same as are presently in effect under the act hereby supplemented.
N.J.S. § 43:13-22.16f