((a)) ** Service included** For purposes of this part, creditable service of a participant includes—
((1)) service as a participant after ;
((2)) service with respect to which deductions and withholdings under section 204(a)(2) of the Federal Employees’ Retirement Contribution Temporary Adjustment Act of 1983 have been made; and
((3)) except as provided in subsection (b), any civilian service performed before (other than service under paragraph (1) or (2)), which, but for the amendment made by section 414 of the Federal Employees’ Retirement System Act of 1986, would be creditable under part I (determined without regard to any deposit or redeposit requirement under such part, subchapter III of chapter 83 of title 5 (the Civil Service Retirement System), or title II of the Central Intelligence Agency Retirement Act ( et seq.), any requirement that the individual become subject to such part, subchapter, or title after performing the service involved, or any requirement that the individual give notice in writing to the official by whom such individual is paid of such individual’s desire to become subject to such part, subchapter, or title).
((b)) ** Refund of retirement deductions; retirement deduction not made; required deposit; computation of interest**
((1)) A participant who has received a refund of retirement deductions under part I with respect to any service described in subsection (a)(3) may not be allowed credit for such service under this part unless such participant deposits into the Fund an amount equal to 1.3 percent of basic pay for such service, with interest.
((2)) A participant may not be allowed credit under this part for any service described in subsection (a)(3) for which retirement deductions under part I have not been made, unless such participant deposits into the Fund an amount equal to 1.3 percent of basic pay for such service, with interest.
((3)) Interest under paragraph (1) or (2) shall be computed in accordance with and regulations issued by the Secretary of State.
((c)) ** Volunteer service; required payment**
((1)) Credit shall be given under this System to a participant for a period of prior satisfactory service as—
((A)) a volunteer or volunteer leader under the Peace Corps Act ( et seq.),
((B)) a volunteer under part A of title VIII of the Economic Opportunity Act of 1964, or
((C)) a full-time volunteer for a period of service of at least 1 year’s duration under part A, B, or C of title I of the Domestic Volunteer Service Act of 1973 ( et seq.),
((2)) The amount of such payments shall be determined in accordance with regulations of the Secretary of State consistent with regulations for making corresponding determinations under chapter 83, title 5, together with interest determined under regulations issued by the Secretary of State.
((d)) ** Prior service under other retirement system; waiver of credit and payment into Fund** Credit shall be given under this System to a participant for a period of prior service under the Federal Employees’ Retirement System (described in chapter 84 of title 5) or under title III of the Central Intelligence Agency Retirement Act ( et seq.) if the participant waives credit under the other retirement system and makes a payment to the Fund equal to the amount which was deducted and withheld from the individual’s basic pay under the other retirement system during the prior creditable service under the other retirement system together with interest on such amount computed in accordance with regulations issued by the Secretary of State.50 U.S.C. 2151
((e)) ** Employees of Members or offices of Congress** A participant who, while on approved leave without pay, serves as a full-time paid employee of a Member or office of the Congress shall continue to make contributions to the Fund based upon the Foreign Service salary rate that would be in effect if the participant were in a pay status. The participant’s employing Member or office in the Congress shall make a contribution (from the appropriation or fund which is used for payment of the salary of the participant) determined under to the Treasury of the United States to the credit of the Fund. All periods of service for which full contributions to the Fund are made under this subsection shall be counted as creditable service for purposes of this part and shall not, unless all retirement credit is transferred, be counted as creditable service under any other Government retirement system.section 4071f(a) of this title