(a) This section applies only to a person who, on or after September 1, 2009:
(1) retires from the employee class; and
(2) is rehired as a retiree into a position that would otherwise include membership in the employee class.
(b) For each month that a department or agency of this state employs a person described by Subsection (a), the department or agency shall remit to the retirement system an amount equal to the amount of the state contribution that the department or agency would remit for an active member employed in the person's position. The amount remitted shall be deposited as provided by Section 815.309.