WASHINGTON — Starting today, 18 additional U.S. ports will begin enforcing the biometric Transportation Worker Identification Credential (TWIC) security card.

The requirement will eventually include about 1.5 million port workers, longshoremen, and truckers who require  access to secure areas of ports.

Most of the ports that begin enforcement Tuesday are in Louisiana and Florida, including New Orleans and Miami. St. Louis and Kansas City ports are also include today. Click here for a complete list.

Compliance is already mandatory at several locations in Maine, new England, and New Hampshire and enforcement begins at most California ports in February. All remaining facilities must comply by April 2009.

The cost for TWIC enrollment is $132.50, although workers with similar threat assessment background check credentials such as hazmat endorsements, or FAST cards may obtain a TWIC card for $105.

Drivers with FAST cards do not have to undergo another security-background check, however.