; and (ii) an assurance to the Secretary that the institution has inquired of and determined the decision of each teacher candidate who has received a scholarship to, within 2 years of completing the program for which a teacher candidate receives a scholarship under this section, begin employment as a teacher, as required by this section. (D) Failure to comply If an individual who receives a scholarship award under this section fails to comply with the agreement signed pursuant to subparagraph (C), the sum of the amounts of any scholarship award received by such recipient shall, upon a determination of such a failure, be treated as a Federal Direct Unsubsidized Stafford Loan under part D of title IV, and shall be subject to repayment, together with interest thereon accruing from the date of the scholarship award, in accordance with terms and conditions specified by the Secretary in regulations under this section. (E) Modified service requirement The Secretary may waive or modify the service requirement of this paragraph in accordance with regulations promulgated by the Secretary with respect to the criteria to determine the circumstances under which compliance with such service requirement is inequitable or represents a substantial hardship. The Secretary may waive the service requirement if compliance by the scholarship recipient is determined to be inequitable or represent a substantial hardship— (i) because the individual is permanently and totally disabled at the time of the waiver request; (ii) because the individual was unable to complete the necessary program of study due to natural disaster