Created to test whether Mexican big rigs can operate safely in the interior of the United States, an official says the a U.S. Department of Transportation cross-border trucking pilot project has not attracted enough participants to draw a reliable conclusion, according to the San Antonio Express-News.

Six months into the one-year program, only 19 Mexican carriers have gained the authority to operate deep within the U.S., far fewer than necessary to extrapolate statistically reliable safety projections, agency Inspector General Calvin Scovel said at a meeting of the U.S. Senate Committee on Commerce, Science & Transportation in Washington.

Of those carriers, the majority have not been making long-haul deliveries, instead dropping loads in the border zones where they previously were confined. "More than 90 percent of trips are inside commercial zones," Scovel said.

The Transportation Department began allowing approved carriers to make deliveries beyond those zones under a pilot program launched in September. The program is supposed to test the safety ramifications of a portion of the North American Free Trade Agreement that allows for

U.S., Mexican and Canadian truckers to make deliveries on one another's soil.

Congress has passed legislation to disallow funding for the endeavor. The Transportation Department maintains the effort can continue because of the law's wording.

"We don't want you to be creative enough and arrogant enough to believe the law doesn't apply to you," Sen. Byron Dorgan, D-N.D., told Transportation Secretary Mary Peters.

The San Antonio Express-News reports that the U.S. and Canada already allow deliveries in one another's countries. Much of the debate surrounding whether the U.S. and

Mexico should have a similar arrangement involves concerns for American trucking jobs and the safety of motorists.

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