Julie Mages, deputy base civil engineer at the 611th Civil Engineer Squadron, and Lauren Oliver, hydraulic engineer at the U.S. Army Corps of Engineers – Alaska District, assess the seawall at Cape Lisburne on Sep. 30, 2019. The protective barrier prevents harsh waves and ice from flooding and damaging the adjacent runway, which serves as the primary avenue for people and supplies to reach the remote military base. The site is operated by the Pacific Air Forces Regional Support Center and provides aerospace surveillance to detect and allow for an early response to potential threats to North America.