Missing security features on the new rail line linking Loudoun County, Virginia, to the Washington D.C. region’s Metro system were identified in a triennial audit by the Tri-State Oversight Committee. Released last month, the nearly 300-page report noted dozens of problems at Metro, but it also highlighted the lapse in planning for the new rail line to include the “additional processes, design features, and equipment necessary in a ‘post-9/11’ environment.” The Metropolitan Washington Airports Authority, which oversees Reagan National and Dulles airports, is supervising construction, but Metro will own and operate the line. Rail project officials said they are awaiting word from Metro about what security elements to include. Among those missing features and policies cited in the audit: closed-circuit televisions currently in use at all Metro stations; technology used to detect weapons of mass destruction and outside intruders on rail tracks; and routine threat and vulnerability assessments, which are used by Metro to gauge how likely or imminent an attack is. A full accounting of Metro’s required security features, which are now being updated, is not publicly available because of its highly sensitive content, officials said. But the failure to include Metro’s security construction and technical guidelines in the plan for the Silver Line could hsave a substantial impact on the project’s ballooning costs.