(A) that participant shall be charged with a contribution deficiency consisting of such unpaid amounts, together with interest thereon, compounded annually; and

(B) such interest on each amount of undeducted contributions shall accrue from the end of the payroll period for which such amount would have been deducted from compensation if he or she had been a participant at the beginning of that payroll period and such deductions had been required for such payroll period until such amount is paid to the retirement system; and

(C) Interest on each such amount included in such participant's contribution deficiency pursuant to this subparagraph (i) shall be calculated as if such additional member contributions never had been paid by such participant, and such interest shall accrue from the end of the payroll period to which an amount of such additional member contributions is attributable, compounded annually, until such amount is paid to the retirement system.

(ii) The rate of interest to be applied to each such amount during the period for which interest accrues on that amount shall be equal to the rate or rates of interest required by law to be used during that same period to credit interest on the accumulated deductions of retirement system members.

(iii) Except as provided in subparagraph (iv) of this paragraph, no interest shall be due on any unpaid additional contributions which are not attributable to the period prior to the first full payroll period referred to in paragraph two of this subdivision.

(iv) Should any person who, pursuant to paragraph seven of this subdivision, has withdrawn any additional member contributions (and any interest paid thereon) again become a participant in the twenty-five year/age fifty improved benefit retirement program pursuant to paragraph five of subdivision b of this section, an appropriate amount shall be included in such participant's contribution deficiency (including interest thereon as calculated pursuant to subparagraph (ii) of this paragraph) for any credited service with respect to which such person received a refund of additional member contributions (including any amount of an unpaid loan balance deemed to have been returned to such person pursuant to paragraph seven of this subdivision), as if such additional member contributions never had been paid. 4. The board of trustees of the retirement system may, consistent with the provisions of this subdivision, promulgate regulations for the payment of the additional member contributions required by this subdivision, and any interest thereon, by a participant in the twenty-five year/age fifty improved benefit retirement program (including the deduction of such contributions, and any interest thereon, from his or her compensation). 5. Where a participant who is otherwise eligible for service retirement pursuant to subdivision c of this section did not prior to the effective date of retirement pay the entire amount of a contribution deficiency chargeable to him or her pursuant to paragraph three of this subdivision, or repay the entire amount of a loan of his or her additional member contributions pursuant to paragraph eight of this subdivision (including accrued interest on such loan), that participant nevertheless shall be eligible to retire pursuant to subdivision c of this section, provided, however, that where such participant is not entitled to a refund of additional member contributions pursuant to paragraph seven of this subdivision, such participant's service retirement benefit calculated pursuant to the applicable provisions of subdivision c of this section shall be reduced by a life annuity (calculated in accordance with the method set forth in subdivision i of section six hundred thirteen-b of this chapter) which is actuarially equivalent to:

(i) the amount of any unpaid contribution deficiency chargeable to such member pursuant to paragraph three of this subdivision; plus

(ii) the amount of any unpaid balance of a loan of his or her additional member contributions pursuant to paragraph eight of this subdivision (including accrued interest on such loan). 6. Subject to the provisions of paragraph five of this subdivision, where a participant has not paid in full any contribution deficiency chargeable to him or her pursuant to paragraph three of this subdivision and a benefit, other than a refund of a member's accumulated deductions or a refund of additional member contributions pursuant to paragraph seven of this subdivision, becomes payable by the retirement system to the participant or to his or her designated beneficiary or estate, the actuarial equivalent of any such unpaid amount shall be deducted from the benefit otherwise payable. 7. (i) All additional member contributions required by this subdivision (and any interest thereon) which are received by the retirement system, shall be paid into its contingent reserve fund and shall be the property of the retirement system. Such additional member contributions (and any interest thereon) shall not for any purpose be deemed to be member contributions or accumulated deductions of a member of the retirement system under section 13-125 or 13-162 of the administrative code while he or she is a participant in the twenty-five year/age fifty improved benefit retirement program or otherwise.

(ii) Should a participant in the twenty-five year/age fifty improved benefit retirement program, who has rendered less than five years of credited service cease to hold a position as an automotive member for any reason whatsoever, his or her accumulated additional member contributions made pursuant to this subdivision (together with any interest thereon paid to the retirement system) which remain credited to such participant's account may be withdrawn by him or her pursuant to procedures promulgated in regulations of the board of trustees of the retirement system, together with interest thereon at the rate of interest required by law to be used to credit interest on the accumulated deductions of retirement system members compounded annually.

(iii) Notwithstanding any other provision of law to the contrary, (A) no person shall be permitted to withdraw from the retirement system any additional member contributions paid pursuant to this subdivision or any interest paid thereon, except pursuant to and in accordance with the preceding subparagraphs of this paragraph; and (B) no person, while he or she is a participant in the twenty-five year/age fifty improved benefit retirement program shall be permitted to withdraw any such additional member contributions or any interest paid thereon pursuant to any of the preceding subparagraphs of this paragraph or otherwise. 8. A participant in the twenty-five year/age fifty improved benefit retirement program shall be permitted to borrow from his or her additional member contributions including any interest paid thereon, which are credited to the additional contributions account established for such participant in the contingent reserve fund of the retirement system. The borrowing from such additional member contributions pursuant to this paragraph shall be governed by the same rights, privileges, obligations and procedures set forth in section six hundred thirteen-b of this chapter which govern the borrowing by members subject to article fifteen of this chapter of member contributions made pursuant to section six hundred thirteen of this chapter. The board of trustees of the retirement system may, consistent with the provisions of this subdivision and the provisions of section six hundred thirteen-b of this chapter as made applicable to this subdivision, promulgate regulations governing the borrowing of such additional member contributions. 9. Wherever a person has an unpaid balance of a loan of his or her additional member contributions pursuant to paragraph eight of this subdivision at the time he or she becomes entitled to a refund of his or her additional member contributions pursuant to subparagraph (ii) of paragraph seven of this subdivision, the amount of such unpaid loan balance (including accrued interest) shall be deemed to have been returned to such member, and the refund of such additional contributions shall be the net amount of such contributions, together with interest thereon in accordance with the provisions of such subparagraph. 10. Notwithstanding any other provision of law to the contrary, the provisions of section one hundred thirty-eight-b of this chapter shall not be applicable to the additional member contributions which are required by this subdivision. 11. Notwithstanding any other provisions of law th the contrary, the additional member contributions which are required by this subdivision shall not be reduced under any program for increased-take-home-pay.