40 CFR § 247.4
Contracting officer requirements
June 9, 2020
Within one year after the effective date of each item designation, contracting officers shall require that vendors:
(a) Certify that the percentage of recovered materials to be used in the performance of the contract will be at least the amount required by applicable specifications or other contractual requirements, and
(b) Estimate the percentage of total material utilized for the performance of the contract which is recovered materials.