SWMU 06 - Mangrove Disposal Site

The Mangrove Disposal Site is located in the ocean-side mangrove swamp in Laguna Arenas along Highway 200. There is no known history of permits pertaining to this site. The site was used during the 1960s and 1970s as a disposal area for general facility wastes. Waste discarded at the site included empty containers of lubricants, oil, solvents, and paints; broken glass; and rubble. The waste materials extend northeast from the Laguna Kiani Bridge approximately 300 feet into the mangrove swamp for 100 to 120 feet in a northerly direction, and about 10 feet in a southerly direction from North Shore Road. The site is adjacent to an access road for public beaches farther west in this part of the island. A fence separates the site from Highway 200, thereby limiting access. While the physical appearance of the waste items may diminish the aesthetic appeal of the site, the 2004 Remedial Investigation concluded that the waste does not pose an unacceptable risk to human health or ecological receptors. However, the Navy and the regulatory agencies agreed that the waste at SWMU 6 poses an unacceptable uncertainty regarding a potential future source of contamination and should be removed. The photo above shows SWMU 6 in October 2009, shortly after waste removal actions. Past Investigations and Actions Environmental Baseline Survey (2000) Expanded Preliminary Assessment/Site Investigation (2000) Removal Actions (2008 thru 2009) Remedial Investigation (2003) Current Site Status A Post-Removal Confirmatory Sampling and Analysis Plan is being developed for additional sediment and surface water sampling.  Field work is anticipated to begin in January 2011. Current Land Use Wildlife refuge, surface water/wetland