The Science Advisory Board has now provided its advice to EPA and the ACOE concerning their proposed rule clarifying the definition of “waters of the United States” under the Clean Water Act. In a brief letter that can only worry the National Farm Bureau and embolden those who thought that the EPA/ACOE proposal did not go far enough, the SAB concluded that:
the available science supports the conclusion that the types of water bodies identified as waters of the United States in the proposed rule exert strong influence on the physical, biological, and chemical integrity of downstream waters.
In fact, the SAB explicitly called for EPA to include within the definition of WOTUS certain categories of waters that the rule would exclude. “Some of the exclusions listed in the proposed rule do not have strong scientific justification and the SAB recommends that several should be reconsidered.”
In a nice little swipe at the lawyers among us, the SAB also found that:
the term “significant nexus” was not well defined in the proposed rule and recommends that the EPA clarify in its general communications and in the preamble to the final rule that “significant nexus” is a legal term, not a scientific term.
I have posted often about the role of EPA’s scientific oversight committees in judicial review of EPA rules. It’s not obvious how that process will play out here, because, as the SAB itself noted, these are legal questions as much as they are scientific questions. However, while the SAB thinks that “significant nexus” is a legal term, I’m not sure that Justice Kennedy agrees. At the very least, he may consider it a mixed question of fact and law and I’d bet that he’d consider the SAB’s conclusion that the science supports the rule relevant in passing on the any final rule promulgated by EPA and ACOE.