Robert L. Borden will be CIO of the South Carolina Retirement System Investment Commission, which oversees the $26 billion South Carolina Retirement System, Columbia. Mr. Borden resigned as executive director of the $7 billion Louisiana State Employees' Retirement System, Baton Rouge, to accept the position, confirmed LASERS spokesman Byron Henderson. Trustees will meet March 24 to begin the process of selecting Mr. Borden's replacement, Mr. Henderson said. Mr. Borden's last day will be April 7. Michael Sponhour, spokesman for the South Carolina fund, directed questions to general counsel Nancy Shealy, who is also administrative director of the investment commission. Ms. Shealy was not available for comment by press time.