; or (B) upon making a determination that a grant is necessary to avert the disruption, strain, compromise, or elimination of a supply chain that would severely affect the national security or economic security of the United States. (3) Maximum Federal involvement Federal assistance other than a grant under this section may be used to satisfy the non-Federal share of the cost of the activity. (j) Loans and loan guarantees (1) In general The Under Secretary may enter into agreements with one or more eligible entities to make a loan, the proceeds of which shall be used to finance eligible activities. (2) Maximum amount The amount of a loan under this section shall not exceed 80 percent of the reasonably anticipated costs of an activity. (3) Waiver Upon providing written justification for a determination made pursuant to this paragraph, which may be submitted with a classified annex to the Committee on Energy and Commerce of the House of Representatives and the Committee on Commerce, Science, and Transportation of the Senate, the Under Secretary may waive the requirement under paragraph (2)— (A) during a period of national emergency declared by an Act of Congress or the President