The Miami-Dade Ethics Commission found no probable cause Thursday to support a complaint against a lobbyist who submitted supplemental documents to a selection committee reviewing proposals from would-be contractors bidding to oversee $1.2 billion in repairs to the county sewer system.

Los Angeles-based AECOM Corp. complained a rival company, Colorado-based CH2M Hill Inc., violated county bidding rules when attorney-lobbyist Mitchell Bierman added a 400-page document to its original presentation just before a second phase of the evaluation process. The commission unanimously found the late submission was not “specifically prohibited” by the bid documents.