Walk into a drayage company dispatch office at any port, and you might think you've accidentally landed at the United Nations. There's a good chance the people around you will be speaking Spanish, Russian, Vietnamese, Laotian, and a host of other languages.

The reason is simple, says David McLaughlin, vice president of RoadLink USA-New England. In many port areas, local drayage jobs—hauling ocean containers between seaports, intermodal yards, and shippers' facilities—have become popular entry-level opportunities for immigrants. As a result, drayage companies like RoadLink have had to hire dispatchers who speak the immigrants' languages.

But things could soon change. Speaking on a panel at the Coalition of New England Companies for Trade's annual Trade and Transportation Conference in April, McLaughlin said he's concerned that the immigrant labor pool will dry up when the Transportation Workers Identification Card (TWIC) rule takes effect. "It's questionable whether they're going to qualify," he said. "They will need a green card, and the government won't be able to conduct background checks on many of them."