WASHINGTON - Frequent border crossers would pay for a new credit card-sized travel document they could use instead of carrying a passport when new ID requirements take effect in June 2009.

All U.S. citizens will need a passport or the new card to enter the country from Mexico or Canada by then. Mexican or Canadian citizens will need similar documents their countries will produce.

The State Department proposed the card and its fee schedule Tuesday, and officials will take comments from the public for two months before moving ahead with production.

The cards would use radio technology that would allow Customs and Border Protection officers to read them from about 20 feet away. Passengers in a car driving across the border, for example, could have their information scanned while they remained in the vehicle.

Border community residents had feared the passport requirement would prove to be an expensive and logistically taxing burden, but the State Department proposal eased some worries.

"Having a passport card is what we'd been advocating as something that would be . . . an easier alternative to a passport," said Jared Peterson, a spokesman for the Border Trade Alliance, a group based in Phoenix.

"Is it going to be affordable for people? Off the top of my head, it seems reasonable."

Officials had said earlier that the card might cost as much as , about half of the price of a passport. Tuesday's proposal cut that to for adults and for children under 16.

Citizens could apply for the cards when they apply for passports. New applications would cost another to pay for security background checks.

The government will have some extra time to process what could be millions of applications. Last month, Congress passed a law delaying the passport requirement for land borders until 2009, rather than the original deadline of early 2008. Business groups and border communities lobbied heavily for the delay.

State Department officials have not decided when to make the cards available.

The technology used in the cards could change before then, though officials plan to use "vicinity" radio frequency chips that can be read from a distance, rather than "proximity" chips that must be within a few feet of the reader.

Privacy advocates have raised concerns that the cards could lead to identity theft, but the State Department proposal says the cards will come with protective sleeves to keep them from being read by would-be thieves.

"The proposal clearly reflects concerns in facilitating legitimate travel for people who live in border communities," said Deborah Meyers, a senior policy analyst at the non-partisan Migration Policy Institute, who has studied post-9/11 border technology. "This is a good example of the government being very responsive to community concerns."

Reach the reporter at mmadden@gannett.com or 1-202-906-8123.