Any provision of law to the contrary notwithstanding, a participant in a work-experience, on-the-job training, or a temporary public service employment position whose salary is paid in whole or in part from federal funds provided under the Comprehensive Employment and Training Act of 1973 (Public Law 93-203; 87 Stat. 839), as amended, shall not be eligible for membership in the system from and after July 1, 1978, except as provided for in this section.
Any such participant who is a member of the system on June 30, 1978, shall remain a member of the system unless the participant elects in writing on a form prescribed by the board to terminate the participant's membership. An election shall not be effective unless filed on or before December 31, 1978. Any participant who elects to terminate the participant's membership in accordance with this section shall be paid all of the participant's accumulated contributions.