concentrates, or products derived therefrom, to carry out inspection, auditing, investigation, or enforcement (not including the collection of royalties, civil or criminal penalties, or other payments) activities under this section in cooperation with the Secretary, and to carry out any other activity described in this section. (2) Except as provided in paragraph (3)(A) of this subsection (relating to trade secrets), and pursuant to a cooperative agreement, the Secretary of Agriculture shall, upon request, have access to all royalty accounting information in the possession of the Secretary respecting the production, removal, or sale of hardrock minerals, concentrates, or products derived therefrom from claims or leases on lands open to location under this Act. (3) Trade secrets, proprietary, and other confidential information protected from disclosure under section 552 of title 5, United States Code, popularly known as the Freedom of Information Act, shall be made available by the Secretary to other Federal agencies as necessary to assure compliance with this Act and other Federal laws. The Secretary, the Secretary of Agriculture, the Administrator of the Environmental Protection Agency, and other Federal officials shall ensure that such information is provided protection in accordance with the requirements of that section. (h) Interest and substantial underreporting assessments (1) In the case of mining claims or leases where royalty payments are not received by the Secretary on the date that such payments are due, the Secretary shall charge interest on such underpayments at the same interest rate as the rate applicable under section 6621(a)(2) of the Internal Revenue Code of 1986. In the case of an underpayment, interest shall be computed and charged only on the amount of the deficiency and not on the total amount. (2) If there is any underreporting of royalty owed on production from a claim or lease for any production month by any person liable for royalty payments under this section, the Secretary shall