With fifteen coal-burning power plants in the state exempt from Clean Air Act standards, the health effects of air pollution from these plants are likely to become more serious with increased temperatures.
(the health effects of air pollution from these plants; are; likely to become more serious with increased temperatures) (the health effects of air pollution from these plants; to become; more serious with increased temperatures)
the health effects of air pollution from these plants the health effects of air pollution from these plants
are to become
likely to become more serious with increased temperatures
more serious with increased temperatures