of a substance which was exported by any person and which, at the time of export, was a taxable carbon substance (as defined in section 9902(1)), credit or refund (without interest) of such tax shall be allowed or made to the person who paid such tax. (B) Condition to allowance No credit or refund shall be allowed or made under subparagraph (A) unless the person who paid the tax establishes that he— (i) has repaid or agreed to repay the amount of the tax to the person who exported the taxable chemical or taxable substance (as so defined), or (ii) has obtained the written consent of such exporter to the allowance of the credit or the making of the refund. (4) Refunds directly to exporter The Secretary shall provide, in regulations, the circumstances under which a credit or refund (without interest) of the tax under section 9901 shall be allowed or made to the person who exported the taxable carbon substance, where— (A) the person who paid the tax waives his claim to the amount of such credit or refund, and (B) the person exporting the taxable carbon substance provides such information as the Secretary may require in such regulations. (5) Regulations The Secretary shall prescribe such regulations as may be necessary to carry out the purposes of this subsection. . (b) Establishment of trust fund (1) In general Subchapter A of chapter 98 of such Code (relating to trust fund code) is amended by adding at the end the following: 9512. Carbon trust fund (a) Creation of trust fund There is established in the Treasury of the United States a trust fund to be known as the Carbon Trust Fund (referred to in this section as the Trust Fund ), consisting of such amounts as may be appropriated or credited to the Trust Fund as provided in this section or section 9602(b). (b) Transfers to trust fund There is hereby appropriated to the Trust Fund an amount equivalent to the amounts received in the Treasury pursuant to section 9901. (c) Expenditures from trust fund (1) In general From amounts in the Trust Fund at the beginning of a