CONCURRING OPINION
Donlon, Judge:I concur. I do so because, as the majority opinion points out, this is a situation governed by subparagraph (f) of paragraph 1615 of the Tariff Act of 1930, rather than by subpara-graph (a). Plaintiff’s sole protest claim is under subparagraph (f).
The cases construing subparagraph (a) of paragraph 1615, or predecessor provisions of earlier tariff acts, are not pertinent. Sludge and scrap may be waste, or residue, within the rule that was laid down in United States v. Tower & Sons, supra, and Burgess Battery Co. v. United States, supra, construing subparagraph (a). They are not the “article previously exported” upon which “allowance or drawback has been made.”