The ruling in a 5-4 decision requires the EPA to consider cost when the agency makes environmental rules. It does not remove the regulations on mercury emissions and does not prohibit the EPA from setting rules. A lower court will have to rule on how the case should be handled. Its likely effect is for the EPA to consider the price for industry compliance in setting environmental rules. The majority decision wirtten by Justice Scalia says the EPA "must consider cost- including, most importantly, cost of compliance- before deciding whether regulation is appropriate and necessary." The current EPA environmental rules were set in 2012, and were put into effect in early 2015. During the early part of the process of setting the rules the EPA did not consider cost. But in the later stages the agency estimated costs of compliance for utility sector at $9.6 billion and public health benefits of at least $37 billion. Justice Elena Kagan alluded to this in her dissenting opinion. Some utilities have received an extension on installing scrubbers to remove mercury pollutants, and these plants would now receive more time. Of the 600 power plants the EPA regulates as part of the rule, 450 are coal fired plants. Of these 35% were given a 1 year extension for compliance. About 21 states heavily dependent on coal and power companies brought this case before the court. ...