(AP)—Federal environmental regulators say they have found lingering radioactive contamination at a rocket engine test site outside of Los Angeles.
The Environmental Protection Agency undertook a $42 million study to look at contamination at the Santa Susana Field Laboratory. The lab tested rocket engines, conducted nuclear energy research and developed nuclear reactors for four decades. A reactor had a partial meltdown in 1959.
Technicians collected some 3,700 soil samples from an area where most of the testing was done. Of those, 10 percent contained radioactive concentrations exceeding background levels.
An EPA official says there are some Superfund sites in the western United States that are more polluted than Santa Susana.
The state of California and various agencies face a 2017 deadline to clean up the site.
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