An environmental group sued some logging companies alleging violations of the Clean Water Act arising from rainwater runoff in logging areas. A statute requires that suits challenging EPA actions be filed within 120 days of the action. On March 20, 2013, the Supreme Court decided that that limitation does not apply to citizen suits seeking to apply permit requirements to forest roads, since another statutory provision allows such suits. The NAM had filed an amicus brief challenging the citizen suit.
Also at issue in the case is the Ninth Circuit’s decision that storm water from logging roads is industrial storm water, in spite of an EPA determination to the contrary. The Court ruled that it was reasonable for EPA to conclude that the water runoff was directly related only to the harvesting of raw materials, rather than to "manufacturing, processing, or raw materials storage areas at an idustrial plant" as defined in the regulation. Thus, the regulation extends only to traditional industrial buildings and not foresting operations.
The decision means that citizen suits can continue to be filed well after regulations are finalized, as long as the suits challenge not the rules themselves, but seek to enforce them under a proper interpretation. The decision also means that EPA's interpretation of a regulation will continue to be given deference by the courts unless it is plainly erroneous or inconsistent with the regulation. This is particularly true where a federal regulation would be duplicative or counterproductive in light of state regulation of the practices at issue.