5 CFR §843.201

1. (a)For payment of employee contributions to the Civil Service Retirement Fund—
   1. (1)As a refund of contribution, to separated employees; or
   2. (2)As a death benefit, to survivors of employees, separated employees, and retirees; and
2. (b)For payment of any accrued, but unpaid, annuity to survivors of retirees.