[§87A-31.5]  Employer contributionsirrevocable.  Notwithstanding any law to the contrary, all of the monthlycontributions that the State and counties make to the fund under sections87A-32, 87A-33, 87A-34, 87A-35, 87A-36, and 87A-37, and all other contributionsthat the State and counties may make to the fund, shall be irrevocable;provided that this shall not preclude the fund from returning contributions orpayments made by the State or any county under a mistake of fact within oneyear after the payment of the contributions or payments. [L 2006, c 57, §2]