This bill changes summer gasoline rules so that gas blended with 10% to 15% ethanol (E10–E15) can be sold year‑round. It extends the same summer waiver that already applies to E10 and updates the law’s wording from 10% to “10 to 15%.” It deals with “vapor pressure,” which is how easily gasoline evaporates and contributes to summer smog. States that previously opted out of this waiver are reset, but they can ask to be excluded again after the bill becomes law if they show it would increase air pollution .

It also directs the Environmental Protection Agency (EPA) to give back certain renewable fuel compliance credits from the 2016–2018 years to qualifying small refineries, or apply those credits to their EPA accounts, under conditions spelled out in the bill .

Key points

• Who is affected: places that sell gasoline and fuel suppliers; state air agencies; small refineries under the renewable fuel program .
• What changes: year‑round sale of E15 by applying the summer waiver; current state exclusions are wiped out but states may reapply; certain past compliance credits must be returned or applied for small refineries .
• When: states may seek a new exclusion after the bill becomes law; the credit changes cover the 2016–2018 compliance years .