33 CFR §148.246

1. (a)If a document to be filed is submitted by mail, it is considered filed on the date it is postmarked. If a document is submitted by hand delivery or electronically, it is considered filed on the date received by the clerk.
2. (b)File all documents and other materials related to an administrative proceeding at the U.S. Coast Guard Administrative Law Center, Attention: Hearing Docket Clerk, room 412, 40 South Gay Street, Baltimore, MD, 21201-4022.