The low-level radioactive materials discovered in the San Carlos home of a scientist who recently died have been safely removed and identified.
The materials found in the property in the 1000 block of Cedar Street, near Burton Park, on Thursday, May 2 prompted authorities to close the park and a nearby youth center. The materials were contained by a county hazmat crew and removed the following morning by state officials for safe disposal.
“Initial survey data indicates that the radioactive materials consisted mostly of Naturally Occurring Radioactive Material (NORM) such as uranium ore samples, a radium clock and other materials with thorium,” according to the city of San Carlos.
County health officials performed two additional sweeps of the home and didn’t find any other radioactive sources. A private firm will head to the property to clean up any household hazardous waste and materials, but there are no threats to the public at the property, the city reported.
Authorities learned about the radioactive materials after receiving a call from the family of Ronald Seefred, who died on Jan. 1 at age 82. Seefred retired in 2003 after 40 years at the SLAC National Accelerator Laboratory in Menlo Park, where he co-authored six radiation physics articles, among other accomplishments. The radioactive materials were found in containers at his house.
Ephrime Mekuria, associate health physicist for the California Department of Public Health, stated that a final list of radioactive materials will be developed for a report. The City of San Carlos said it will make the report available on its website once it is received.