A participant who has no eligible survivor's annuity beneficiary may elect to cease making contributions for survivor's annuity under this subsection. A survivor's annuity shall not be payable upon the death of a person who has made this election, unless prior to that death the election has been revoked and the amount of the contributions that would have been paid under this subsection in the absence of the election is paid to the System, together with interest at the rate of 4% per year from the date the contributions would have been made to the date of payment.
40 ILCS 5/2-126