The Environmental Protection Agency (EPA) is conditionally approving a revision to the Tennessee State Implementation Plan (SIP) submitted by the State of Tennessee, through the Tennessee Department of Environment and Conservation (TDEC), through a letter dated August 11, 2021. This revision establishes alternative monitoring, recordkeeping, and reporting requirements under the Nitrogen Oxides (NO<INF>X</INF>) SIP Call. EPA is approving these changes pursuant to the Clean Air Act (CAA or Act).