Rising water temperatures and severe algae blooms in cooling canals have threatened to shut down two nuclear reactors at Florida Power & Light's Turkey Point plant near Miami.
Federal regulators said there is not a public safety risk. But over the past few weeks the canal temperatures have come within one degree of a 100-degree federal limit that requires an expensive shutdown.
In a letter to state regulators last month, FPL asked to control algae with herbicides and to cool the canals with daily injections of millions of gallons from an underground reservoir that supplies Miami-Dade County's drinking water. The request drew questions from environmentalists.
The agency also asked federal regulators to increase the operating limit to 104 degrees.