FULTON, Mo. (AP) - A Missouri environmental group is renewing its calls for federal regulators to delay issuing a 20-year extension for the Callaway County nuclear power plant until legal challenges regarding spent fuel rod storage are resolved.

The Missouri Coalition for the Environment filed its request with the Nuclear Regulatory Commission on Monday. The federal agency expects to rule soon on utility provider Ameren's license extension for the Fulton plant, which was filed in 2011. The state's only commercial nuclear power plant is currently licensed to operate until 2024.

A recent lawsuit against the nuclear agency objects to new rules allowing above-ground storage of spent fuel after years of failed efforts to build a permanent national storage site in Nevada.

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