The Environmental Protection Agency is in the midst of reviewing a set of proposed revisions to water quality standards in North Carolina.

The standards were approved by the N.C. Environmental Management Commission in response to federal requirements that state periodically evaluate surface water standards and integrate recent research. 

Changes to the standards include:

• Changing some standards to regulate dissolved metal concentrations instead of total recoverable concentrations where the dissolved metal number more accurately describes the portion of metal that’s toxic. 

• Considering the effect of water hardness on metal toxicity. 

• Instituting health-protective standards for 2,4-D, a widely used herbicide. 

• Updating aquatic life protective concentrations arsenic, beryllium, cadmium, chromium III, chromium VI, copper, lead, nickel, silver and zinc.

• Clarifying when site-specific standards can be developed after studies are done in accordance with guidance from the EPA. 

Two public hearings were held in July to gather input on the proposed changes, and a report summarizing the issues and comments is available at portal.ncdenr.org/web/ emc/november-13-2014.