The Department of Homeland Security (DHS) has not established comprehensive standard operating procedures for addressing cross-border tunnels, and … relevant officials were not aware of all DHS systems or offices with tunnel information.
In addition, “DHS has not assessed and documented how all of the alternative ultralight aircraft technical solutions it is considering will fully address 
operational requirements or the costs and benefits associated with these different solutions. This type of analysis could help better position DHS to use its resources effectively and ensure that operational needs are met, consistent with risk management best practices,” according to a public version of a For Official Use Only—Law Enforcement Sensitive Government Accountability Office (GAO) audit report issued in February 2017.
In the redacted public report, GAO said that, “By establishing procedures for addressing cross-border tunnels, DHS could provide strategic guidance and facilitate information sharing department-wide, consistent with standards for internal control. DHS has also invested or plans to invest in at least five technology projects to help detect and track ultralight aircraft.”
According to GAO, “DHS has established various coordination mechanisms and invested in technology to address select smuggling methods in the subterranean, aerial, and maritime domains,” such as establishing interagency task forces to investigate cross-border tunnels.”
GAO’s analysis of DHS data “showed there were 67 discovered cross-border tunnels, 534 detected ultralight aircraft incursions and 309 detected drug smuggling incidents involving panga boats (a fishing vessel) and recreational vessels along US mainland borders from Fiscal Years 2011 through 2016.”
While the “number of known smuggling events involving these me
thods generally declined over this period,” GAO reported, it noted “they remain threats.”
While “DHS has established high-level smuggling performance measures and collects data on smuggling bytunnels, ultralight aircraft, panga boats and recreational vessels,” GAO said, it also determined that, “DHS has not assessed its efforts specific to addressing these smuggling methods to, for example, compare the percent of detected panga boat and recreational smuggling events that are interdicted against targeted performance levels.”
GAO said, “By establishing measures and regularly monitoring performance against targets, managers could obtain valuable information on successful approaches and areas that could be improved to help ensure that technology investments and operational responses to address these smuggling methods are effective, consistent with standards for internal control.”
GAO made six recommendations, including that DHS establish procedures for addressing tunnels, assess ultralight aircraft technology and establish performance measures and targets.
DHS concurred with four recommendations, but “disagreed with those to establish tunnel procedures and maritime performance measures, citing other efforts.”
GAO said it “believes the recommendations remain valid, as discussed in the report.”
