Members of the faculties and such other employees exempt from civil service pursuant to RCW
41.06.070 (1)(z) and (2) as are designated by the boards of regents of the state universities, the boards of trustees of the regional universities and of The Evergreen State College, the student achievement council, or the state board for community and technical colleges who do not opt to become members of the teachers' retirement system or the public employees' retirement system under RCW
41.32.836 or
41.40.798, or who are not prevented from participation in an annuity or retirement plan under RCW
28B.10.400(2) shall be required to contribute not less than five percent of their salaries during each year of full-time service after the first two years of such service toward the purchase of such annuity or retirement income plan; such contributions may be in addition to federal social security tax contributions, if any.