ENV-09-20 Navigating the NPDES Antidegradation Process: A Success Story

Description:

Antidegradation—the regulatory process to maintain existing water quality and protect high quality waters—does not have to strike fear in the hearts of the regulated community. Recently, Marathon Oil Corporation wholly owned subsidiary, Marathon Petroleum Company LLC and its Ohio Refining Division (Marathon) successfully completed an Antidegradation Assessment (AA) for an outfall relocation project. The catalyst for the AA emerged from the refinery’s August 2005 renewed National Pollutant Discharge Elimination System (NPDES) permit that included new water quality based effluent limitations (WQBELs) for three parameters: temperature, total fluoride and total dissolved solids (TDS). A careful analysis of engineering options identified economically achievable alternatives for temperature and fluoride compliance; however, a practical solution for TDS compliance was not available. The preferred alternative, outfall relocation, was identified as the most cost-effective TDS compliance engineering alternative. However, it created two new obstacles: New Source Performance Standards (NSPS) and successful approval of the AA. Through this case history, Marathon will share the efforts taken to successfully demonstrate that antidegradation associated with outfall relocation to a new receiving stream was socio-economically prudent and the best engineering alternative for compliance with the renewed NPDES permit.