Federal officials say a six-acre plot in northern New Jersey that was once contaminated with radioactive thorium has been officially removed from the nation's Superfund list.

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The former W.R. Grace and Co. site in Wayne underwent $125 million in cleanup efforts over 20 years.

Officials in the Passaic County community plan to turn the site into a dog park and playground. It had been on the Superfund list for nearly three decades before its removal was formally announced on Tuesday.

Grace ceased operations at the site in 1971 and decontaminated the property in 1974 to the standards in place at the time.

But an aerial survey conducted by the state in 1980 showed elevated radiation levels there and other nearby sites.

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