The following are the answers to the question presented:
Human system: Crystal River Nuclear Plant
Physical system: St. Johns River
The Crystal River 3 Nuclear Power Plant, also simply called the Crystal River Nuclear Plant, is a closed nuclear power plant located in Crystal River, Florida.
The St. Johns River is the longest river in the U.S. state of Florida and its most significant for commercial and recreational use. At 310 miles long, it winds through or borders twelve counties, three of which are the state's largest.
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