The Guam Environmental Protection Agency will be hosting a public meeting at Merizo Pier Park on Friday to discuss the results of the National Oceanic and Atmospheric Administration's assessments on waters around Cocos Island as well as the preliminary results of a turbidity and nutrient study in three rivers draining into the Achang Reef Flat Marine Preserve.
The public will also hear about the U.S. Coast Guard Cocos Island Remediation Project and Cocos Lagoon Tire Reef Removal Project.
The island is the former site of the U.S. Coast Guard Long Range Navigation station (LORAN) and components of that station, including items containing polychlorinated biphenyls, or PCBs, were found on land and in nearby waters.
"Exposure to PCBs can lead to a range of toxic responses according to animal studies, including reduced growth, reproductive impairment, and vertebral abnormalities. PCBs have also caused cancer in animals," according to NOAA.
The LORAN station operated between 1944 and 1963.
The Coast Guard removed the components and a substantial amount of contaminated soil but there is evidence the chemicals migrated into fish and nearshore sediments - a concern for local natural resource managers and the public, NOAA stated.
According to the 2017 report, there are low levels of chemical contaminants in sediment but the pesticide DDT was somewhat elevated in sediment on the northern end of the island, exceeding NOAA sediment guidelines.
"Elevated levels of (PCBs) along with the pesticide DDT, however, were found in most fish collected adjacent to Cocos Island. A number of the fish contained concentrations of both PCBs and DDT above subsistence and even recreational fisher screening values established by the U.S. Environmental Protection Agency," according to the 2017 report.
There were lower concentrations of PCBs and DDT in fish from other areas of the Cocos lagoon but some still contained levels above NOAA screening values.
For the 2019 report, certain water sampling devices were used to determine if contaminants in the water column contributed greatly to contamination in aquatic life.
PCB and DDT detections were limited to nearshore sites, according to the report. The highest concentrations were located adjacent to the former LORAN site.
"From this work, it appears that uptake of these contaminants directly from the water column into biota such as fish in nearshore areas, likely occurs, however, accumulation through the food chain may also be important," the 2019 report stated.