Individual blenders could rely on your association to submit reports to EPA on their behalf. . However you should understand that if any reports are not submitted or are submitted improperly then responsibility would fall upon the individual blender. More information may be found at Reporting for Fuel Programs.
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)