Indian Point Energy Center (IPEC) is a commercial nuclear power generating station located in Westchester County, on the eastern shore of the Hudson River. IPEC is owned and operated by Entergy Nuclear and consists of two operating pressurized water reactors (Units 2 and 3) and one defueled reactor (Unit 1). The spent fuel pool for Unit 1 has been emptied of fuel and water. The spent fuel pools for Units 2 and 3 are both near their maximum capacity for storing spent fuel. As a result, Entergy has begun removing the older fuel assemblies and placing them into dry cask storage on-site, north of Unit 2.
Discovery of Contamination
In late 2005, as part of the preparations for starting fuel transfers to dry cask storage, Entergy began installation of a new crane at the Unit 2 spent fuel pool building. During that activity they discovered spent fuel pool water was leaking into the underlying groundwater, creating a tritium (H-3) groundwater plume. During efforts to map the extent of the H-3 plume, another radionuclide, strontium 90 (Sr-90) was discovered. Entergy determined that the source for this groundwater contaminant was the Unit 1 spent fuel pool (later emptied of fuel and water to stop this contamination source.)
Investigation by the State
Both the NYS DEC and DOH participated in the investigation into the sources for, and extent of the plumes. The investigation showed that site groundwater flows generally westward, eventually making its way into the Hudson River. Given that Sr-90 can accumulate in the flesh and bones of fish and crustaceans, the State agencies, with the support of the Nuclear Regulatory Commission, requested that Entergy expand their Radiological Environmental Monitoring Program (REMP) to include Sr-90 in fish flesh. The results of the 2006 REMP found no differences in Sr-90 concentrations in fish caught near the plant and those caught upriver at a control location near Newburgh, and no public health threat from consumption of fish caught in the Hudson as a result of the Sr-90 groundwater flow into the river.
State review of the REMP report raised the possibility of overlap in range of the fish from these two locations which introduced some uncertainty in the results of the finding from the enhanced 2006 REMP. Therefore the State agencies requested another enhancement of the REMP in 2007, adding a third location near the village of Catskill, well upstream of any potential impact from IPEC and any possibility of fish population overlap. In addition, based upon requests from interested members of the public, the State agencies agreed to analyze Sr-90 concentrations in fish bone. Given that strontium is analogous to calcium in its behavior in the environment, it tends to concentrate in bone to a greater degree than in flesh, making analysis of bones a more sensitive environmental indicator for the presence of Sr-90.
The results of the 2007 enhanced REMP analyses again showed no differences in Sr-90 concentration in fish flesh between fish caught near IPEC and those caught near Newburgh. There was also no difference between in flesh concentrations in fish caught at either of these locations and the fish caught near Catskill. Additionally, there was no difference in the more sensitive indicator of Sr-90 concentrations in fish bones caught in these three locations.
The conclusion of the DEC is that there is no measurable difference in Sr-90 concentrations in fish flesh or bone between fish caught near IPEC and those caught in unaffected areas of the river, i.e., no measurable impact to Sr-90 concentrations in fish from the site groundwater entering the Hudson. This reinforces the previous determination made by the DOH that there is no public health concern, relative to Sr-90, related to eating fish caught in the Hudson River.
In addition, the DEC's Division of Fish, Wildlife and Marine Resources reviewed currently available guidance on impacts to wildlife from radioactive materials in the environment and compared those guidance values with the concentrations of radionuclides detected in the fish samples from this study. The concluded that the levels of radionuclides - including 90Sr - were two to five orders of magnitude lower than criteria established for protection of freshwater ecosystems.
A link is provided in the right column to supply the public with access to read the full report, "Measurement of Strontium-90 (90Sr) and Other Radionuclides in Edible Tissues and Bone/Carapace of Fish and Blue Crabs from the Lower Hudson River, New York".