Geospatial data for contaminants at Palmyra Atoll, 2008 and 2010

Palmyra atoll includes nearly 50 square kilometers of coral reef and 275 hectares of emergent lands that include forests of endangered Pisonia grandis trees and colonies of several species of birds. The reef is considered pristine, but some land areas and nearshore sediments are chemically contaminated from activities that occurred during the occupation of the atoll by the US Navy during World War II. In 2008 and 2010, a screening survey was conducted to measure toxic elements in soils and sediments at locations known or suspected to be contaminated. A map of Navy facilities on the atoll in 1944 was scanned, mosaicked, and georeferenced, and identifiable facilities were digitized and attributed with information from the map legend. This geospatial data provided the framework for a targeted survey of contamination in soils and sediment on and around the atoll, using a hand-held X-Ray Fluorometer (XRF) to measure the concentration of 25 elements. Results identify dozens of locations where concentrations of toxic elements exceeded established terrestrial soil and marine sediment thresholds above which adverse ecological effects are expected. The map of naval facilities and the locations of XRF samples were compiled into a geospatial database to alert resource managers to potential issues on the atoll and to inform potential remediation and habitat restoration activities. Deployment locations for passive organic contaminant samplers known and Semi-Permeable Membrane Devices (SPMD) are also provided. As of March 2017, SPMDs had not been analyzed for organic contaminants.