S. 1638 became law 316 days after introduction, with one cosponsor, a Democrat

(This measure has not been amended since it was reported to the Senate on March 14, 2016. The summary of that version is repeated here.) Department of Homeland Security Headquarters Consolidation Accountability Act of 2015

(Sec. 2) This bill directs the Department of Homeland Security (DHS), in coordination with the General Services Administration (GSA), to submit information on the implementation of the enhanced plan for the DHS headquarters consolidation project within the National Capital Region, approved by the Office of Management and Budget and included in the budget of the President for FY2016, that includes: a proposed occupancy plan that includes specific information about which DHS-wide operations, component operations, and support offices will be located at the site, the aggregate number of full time equivalent employees projected to occupy the site, the seat-to-staff ratio at the site, and schedule estimates for migrating operations to the site; a comprehensive assessment of the difference between the current real property and facilities needed by DHS in the Region to carry out its mission and its future needs; an analysis of the difference between the current and needed capital assets and facilities of DHS; a current plan for construction of the headquarters consolidation at the St. Elizabeths campus that includes the estimated costs and schedule for the current plan and any estimated cost savings associated with reducing the scope of the project and increasing the use of existing capacity developed under the project; a current plan for the leased portfolio of DHS in the Region that includes an end-state vision that identifies which DHS-wide operations, component operations, and support offices do not migrate to the St. Elizabeths campus and continue to operate at a property in the leased portfolio, the number of full-time equivalent employees who are expected to operate at each property, component, or office for each year until the consolidation project is completed, the anticipated total rentable square feet leased per year between the date of this Act's enactment and the date on which the consolidation project is completed, and the timing and anticipated lease terms for leased space; and an analysis that identifies the costs and benefits of leasing and construction alternatives for the remainder of the consolidation project, including a comparison of the long-term cost that would result from leasing to the cost of consolidating functions on government-owned space and the identification of any cost impacts in terms of premiums for short-term lease extensions or holdovers due to the uncertainty of funding for, or delays in, completing construction required for the consolidation. The bill directs the Government Accountability Office to evaluate the quality and reliability of the cost and schedule estimates submitted and report on the results.