Where it appears that, by reason of estimated profits to be derived through the recovery of wastes, through separate charges for use of the facility in question, or otherwise in the operation of such facility, all or a portion of its costs may be recovered over the period referred to in paragraph (a)(6) of 26 CFR 1.169-2, the Regional Administrator shall so signify in the notice of certification. Determinations as to the meaning of the term estimated profits and as to the percentage of the cost of a certified facility which will be recovered over such period shall be made by the Secretary of the Treasury, or his delegate: Provided, That in no event shall estimated profits be deemed to arise from the use or reuse by the applicant of recovered waste.