Who actually calculates the RVO? The refinery or EPA?

Each obligated party calculates the RVO itself, based on its annual gasoline volume. See regulation Sections 80.1152(a)(1)(v) and (vi).

Question and Answer was originally posted at: Questions and Answers on the Renewable Fuel Standard Program (PDF) (55 pp, 221 K, EPA420-F-07-041a, August 2007, About PDF)