Justice Potter Stewart famously said, with respect to obscenity, that “I know it when I see it.” I fear that the test for what constitutes an imminent and substantial endangerment under RCRA is no clearer than Justice Stewart’s subjective test regarding obscenity.

This week, in a decision that is good news for RCRA defendants, Judge Illlston, of the Northern District of California, ruled, in West Coast Home Builders v. Aventis Cropscience USA, that risks posed by potential future vapor intrusion into buildings from a groundwater plume could not be “imminent and substantial” where no development has yet occurred on the property that is the subject of the litigation. The court was interpreting the Supreme Court’s statement in Meghrig v. KFC Western, to the effect that RCRA “implies that there must be a threat which is present now, although the impact of the threat may not be felt until later.”

Although Judge Illston’s interpretation of Meghrig seems right, other RCRA cases have been allowed to proceed, even though the relationship between the contamination and the exposure have often been equally attenuated. It seems that the court liked the simplicity of a black-letter rule that risks associated with conditions not yet in place can never be imminent. I am not confident this case will provide much clarity, but even if it only establishes a bright line rule in one narrow corner of the "imminent and substantial endangerment" landscape, that's better than the prior morass.

A developer might reasonably respond to this decision by arguing that such a ruling means that the development will never happen, because no one will finance such a project without knowing that the potential vapor intrusion risk will be addressed. (And a court might respond by saying that that is a problem for Congress to solve, not the courts.)