Under the program, those driving trucks built before 1994 can get $5,000 if they junk their old ride and buy a 2004 or newer model. To qualify, drivers have to be frequent users of the port, averaging one visit a week during the previous year.
Authority spokesman Byron Miller said about 10% of the port's frequent users, about 260 trucks, qualify for the incentive.
The project is being funded by both the authority and through an Environmental Protection Agency grant administered through the state Department of Health and Environmental Control. Each is paying half of the incentive with the authority also paying the administrative costs of the program.
Officials hope to get 100 trucks replaced during the first phase of the voluntary program.