January 8th National Memorial Act This bill directs the Department of the Interior to establish the January 8th National Memorial in Tucson, Arizona, as an affiliated area of the National Park System in commemoration of the shooting of Congresswoman Gabrielle Giffords and 18 others in Tucson on January 8, 2011. The January 8th Memorial Foundation shall transfer to Pima County the total amount of final funding pledges, in addition to the amounts that the foundation has raised and transferred to the county for the construction of the memorial. The memorial shall be constructed on land owned by Pima County. The bill makes the county responsible for managing the construction contract for the memorial using the funds provided by the foundation which were pledged, raised, and transferred. The foundation shall cease its operations on the later of when (1) final funding pledge amounts have been paid to Pima County, or (2) construction of the memorial has been completed. Pima County shall (1) be the memorial's management entity, and (2) be responsible for the construction and operation of the memorial. Interior shall develop a general management plan for the memorial.