A Traffic Mitigation Fee (TMF) is a fee paid when a terminal becomes congested. It covers the added cost of workers forced to operate outside of normal hours to avoid delays and loss of business.
In 2005, a program called OffPeak was instituted by PierPASS to alleviate frequent delays at the Los Angeles and Long Beach terminals in California. Any shipment processed during peak hours at those terminals (M-F, 3 AM – 6 PM) now incurs a TMF to cover off-peak shifts (weeknights and Saturdays).