High levels of a radioactive material — nearly three times the amount permitted in drinking water — were found in groundwater near the Hudson River beneath a nuclear plant, the owner said Tuesday.
The groundwater does not intersect drinking supplies, and although the strontium-90 is believed to have reached the Hudson it would be safely diluted in the river, said Jim Steets, spokesman for Entergy Nuclear Northeast.
The strontium — which in high doses can cause cancer — was found in a well dug in a search for the source of a leak of radioactive water at the Indian Point complex, about 30 miles north of New York City.
The test well is among nine dug in an attempt to pinpoint the leak. Contaminated water was first found in August.
Entergy’s finding matched tests by the Nuclear Regulatory Commission on the same sample, Steets said.
The sample also yielded tritium, another potential carcinogen, at levels well above the drinking water standard. High levels had been found earlier in another test well. The nuclear commission announced Monday that it would investigate releases of tritium at Indian Point and other plants.
Regulatory agency response
NRC spokesman Neil Sheehan said Tuesday that the commission still believes that radioactivity in the water — given that it is not drinking water — is well below the level that would "pose a risk to public health and safety."
The sample from the well also found higher-than-normal levels of a third isotope, nickel-63, but those levels were under the drinking water standard, Steets said.
The test well, inside a turbine building, is among nine recently dug in an attempt to pinpoint the leak that is contaminating the groundwater. Contaminated water first was found in August on the outside of a spent-fuel pool for the Indian Point 2 reactor, but no leak has been found on the inside of the pool.
The new findings add to the uncertainty, Steets said.
"When we first got these findings we were scratching our heads because it does raise questions about what the source (of the leak) really is," Steets said.
‘Still all speculation’
For example, he said, the presence of nickel might point to the spent-fuel pool for Indian Point 1 rather than Indian Point 2 because those fuel assemblies had more steel and nickel-63 is formed in connection with steel.
"It's still all speculation," he added. "This is just one data point in a long process."
Entergy said water samples were taken at four depths in the well. Strontium levels, in picocuries per liter, were 2.4, 3.86, 18.2, and 22.7. The drinking water limit is 8.
Tritium, which becomes dangerous only at much higher concentrations than strontium, was found at 12,800, 14,700, 28,000 and 13,300 picocuries per liter. The drinking water limit is 20,000.