Naval Heritage & History Command (NHHC), at the Washington Navy Yard, is an Echelon II command responsible for preservation, analysis, and dissemination of US Naval history and heritage. NHHC underwent Design|Build renovations of the historic facility housing the collection. Work included hazardous remediation of the building, and mold from the historic TS Navy and NATO documents housed within. Anti-Terrorist upgrades included new windows and electrical features. A major HVAC upgrade was performed to properly condition the space to protect the documents from future risk, and was completed in four phases to allow Archive staff maximum access to documents at any time.