Notwithstanding any other provision of this section, any service performed by an individual described under subsection (a) of this section as an employee of the Senate day care center is deemed to be civilian service creditable under section
8411 of title
5 for purposes of qualifying for survivor annuities and disability benefits under subchapters IV and V of chapter 84 of such title, if such individual makes payment of an amount, determined by the Office of Personnel Management, which would have been deducted and withheld from the basic pay of such individual if such individual had been an employee subject to section
8422 of title
5 for such period so credited, together with interest thereon.