EPA published a final rule on June 7, 2017 (82 FR 26354) that relaxed the 7.8 psi federal Reid Vapor Pressure (RVP) requirement for Nashville (Middle Tennessee counties of Davidson, Rutherford, Sumner, Williamson, and Wilson Counties). The final rule approves the Tennessee Department of Environment and Conservation’s (TDEC) request to change the summertime gasoline RVP standard for Middle Tennessee from 7.8 psi to 9.0 psi. Previously, these counties were required to use 7.8 psi gasoline from June 1 to September 15 as part of an EPA-approved maintenance plan for Middle Tennessee to meet the 1997 ozone National Ambient Air Quality Standard (NAAQS). Similar relaxations have been approved for cities in Alabama, North Carolina, Florida, and Louisiana.
TDEC Air Pollution Control successfully demonstrated that relaxing the standard to 9.0 psi would not interfere with the air quality in Middle Tennessee. In the final rule, EPA states:
EPA evaluated the impacts on air quality associated with the change in RVP requirements and determined that any such impacts will not interfere with attainment or maintenance of any NAAQS or with any other applicable requirement of the Clean Air Act (82 FR 11517, 11520-11522, Feb. 24, 2017).
What this action means: Effective June 7, 2017, these counties are no longer subject to the 7.8 psi federal volatility requirement to use the 7.8 psi as the summer blend gasoline from the period of June 1 to September 15.
What this means for you: Improved fuel security for Tennessee
The change to 7.8 psi summer blend fuel in mid-May and then back to 9.0 psi in mid-September created vulnerability in the fuel supply chain for Nashville. The last two major fuel shortages in Nashville in 2008 and 2016 both occurred during September when inventories were lower than normal due to the need to deplete the summer blend stock. With this change, Nashville is more resilient to disruptions to its fuel supply.
“With this final rulemaking, the gasoline sold in the Middle Tennessee Area can be identical to the fuel sold now in most of the rest of Tennessee. For motorists, the change in summertime gasoline volatility specifications will be virtually unnoticed,” said U.S. EPA in their official Regulatory Announcement on Relaxing the Standard: https://www.epa.gov/sites/production/files/2017-06/documents/420f17011.pdf