On December 14, EPA formally rejected a petition from the Natural Resources Defense Council (NRDC) to update national secondary treatment standards for wastewater utilities to include nitrogen and phosphorus removal. EPA based its decision on the lack of a universal need for new standards and the high costs to some treatment plants. EPA also rejected NRDC’s request to publish the most recent data on secondary treatment technology to remove nitrogen and phosphorus, saying the available data on the technology are inconclusive. EPA did agree to publish the most updated information on secondary treatment for all other pollutants that are currently regulated.
“We find that a uniform set of nationally applicable, technology-based nutrient limits is not warranted at this time,” Michael Shapiro, EPA deputy assistant administrator for water, wrote in EPA’s letter to the environmental group. “An effort to set such national standards would require publicly owned treatment works to incur high costs even where such costs are not necessary to protect water quality.” Reducing nutrient pollution is among EPA’s top priorities, according to Shapiro. But he said, “We conclude that the need to control nutrients is a highly site specific matter that is not well-suited to being carried out through a uniform national rule; that not all POTWs nationwide need minimum technology based limits for nutrients to protect water quality; and that many POTWs would incur high costs individually.” Instead, Shapiro indicated that the Clean Water Act and the water quality-based permitting regime gives EPA and states the flexibility to decide establish nutrient controls where they are needed.
EPA’s response to NRDC’s petition, which was filed five years ago, came as a result of a lawsuit that NRDC filed in March 2012 seeking action on its petition.