From Environmental Capital:
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Specifically, the court said, using the “best available technology” to tackle any given environmental problem means using the most efficient approach—not necessarily the best technology if it is prohibitively expensive.
The ruling addresses a huge question in the energy and environment battle raging right now—namely, how to strike the balance between environmental protections and safeguarding the economy. It also brings the field of cost-benefit analysis squarely back into the environmental debate. ...
The ruling is “likely to be highly influential in granting EPA discretion to use cost-benefit analysis more generally,” said Tim Bishop, a partner in the Supreme Court and Appellate practice at Mayer Brown law firm. It will probably bolster those “who argue that economic analysis is an important part of the equation when government mandates environmental protections–a battle that has intensified in recent years,” he said.
That’s why today’s Supreme Court ruling could be good news for the environment in the long run. It may have ruled out some best-in-class, but very expensive, environmental regulations. By allowing cost-benefit analysis to prevail, there will be fewer outlandish environmental expenses–and therefore less pushback from the business community.