practicable, ensure that the start of full operations of the facility described in paragraph (1) occurs before December 31, 2026. (4) Reporting The Secretary shall include in the annual budget request of the Department an explanation for any delay in the process of the Department in completing the facility described in paragraph (1) by the deadline described in paragraph (3). (5) Coordination The Secretary shall leverage the best practices for management, construction, and operation of national user facilities from the Office of Science. (6) Authorization of appropriations There are authorized to be appropriated to the Secretary for the Office of Nuclear Energy to carry out to completion the construction of the facility under this subsection— (A) $300,000,000 for fiscal year 2021