An executive with Huntsman Corp. told federal lawmakers Tuesday that his company has suffered repeatedly from the Union Pacific-Southern Pacific Railroad merger and the subsequent Union Pacific bottlenecks.

Jon Huntsman Jr., vice president of the corporation based in Salt Lake City, told the U.S. Senate's surface transportation subcommittee that his firm has had numerous problems in Texas including a derailment of $100,000 worth of plastic pellets near Roscoe, a two-week plant shutdown in Port Neches, Texas, and bottlenecks to and from a factory in Odessa, according to the Dallas Morning News."Rail cars have been unable to get past the Fort Worth choke-point," Huntsman said.

Lawmakers expressed frustration with a federal oversight board's response to costly tie-ups along Union Pacific rail lines, as that board's chairman insisted she has the power to act and has moved quickly to use it.

"I have made the tough decisions, and we have moved forward," said the Surface Transportation Board's chairman, Linda Morgan, who said the board was working within the guidelines set by Congress.

"What we don't want is for the board to begin asserting responsibility and then have people saying, `Well, that's not what the board should be doing,' " Morgan told the Senate's surface transportation subcommittee.

But even the board's announcement, made earlier in the day, of more intensive oversight of last year's merger between Union Pacific and Southern Pacific did little to assuage the senators.

Backed up by witnesses who said the price to farmers and businesses from clogged Union Pacific tracks was now reaching into the billions of dollars, members of the Senate panel said the board either lacked authority or wasn't using it fully.

"I hope you are going to be looking closely at these policies," Kansas Sen. Sam Brownback, a Republican, told Morgan. "Otherwise, we're going to continue to have these mountains of grain" that aren't shipped.

"If the authorization doesn't exist, and you're not asking for the authorization, then maybe we should abolish the board," Sen. Byron Dorgan, a North Dakota Democrat, said, in a refrain that seemed to gain popularity among senators as the hearing wore on early into the evening.

The panel's chairman, Texas Sen. Kay Bailey Hutchison, a Republican, pledged to examine ways to toughen the board's mandate - to among other things make competition "the primary concern" when the board evaluates proposed mergers.

Union Pacific's purchase of rival Southern Pacific, which was opposed by the Justice Department but approved by the STB, gave the company control over a 36,000-mile network of tracks, stretching from Los Angeles to New Orleans and north to Chicago.

Rail shipping across the West began to deteriorate in the summer of 1997, soon after Union Pacific began merging its rail lines with those of its former rival and fired hundreds of workers.