The promoter of Washington's inaugural Grand Prix auto race misled D.C. regulators by claiming that a Canadian expert would build a high-tech sound wall at the 1.7-mile track, according to interviews and city records.

In a July 2 letter, promoter Christopher J. Lencheski told the District's chief regulator that Calgary-based Portable Fence Systems Ltd. would install a sound-dampening barrier along an estimated 700-foot stretch of the racecourse. He also wrote that the designer would "personally oversee construction and installation" of the sound wall.

The document was submitted in response to questions from the D.C. Department of Consumer and Regulatory Affairs that were part of the city's environmental review of the Grand Prix.

But George Bittman, president of the Canadian company, said in an interview last week that his firm provides only security fences and did not erect the sound wall built for last weekend's Cadillac Grand Prix of Washington, D.C.

Bittman said he built a 150-foot test sound wall in 1981 and, beginning late last year, had several discussions with Lencheski's company about possibly designing a wall for the Grand Prix. But an agreement never materialized. Early this month, with the race less than two weeks away, Bittman said he called the promoter to see whether his assistance was needed. He never heard back.

"Over the course of several months, they asked me details about the [sound] fence, and I told them. And that was extent of my involvement in the Washington Grand Prix," Bittman said. "There was never a firm commitment for me to come down to oversee the construction of the wall."

Lencheski, chairman of the board of North Carolina-based National Grand Prix Holdings LLC, declined last week to answer questions about his letter or to say who constructed the sound buffer used for the event. Instead, he issued a brief, written statement hailing the success of the race and saying that his company is looking into ways to diminish the noise from the 2003 Grand Prix.

Race organizers had touted the sound-dampening fence as a cutting-edge measure and said they hoped it would ease nearby residents' concerns about the noise generated by cars speeding on a temporary track on the parking lots of Robert F. Kennedy Memorial Stadium within 50 yards of homes.

But the wall -- which city inspectors found measured only 584 feet long -- was constructed with sizable gaps between some sections, and over the weekend, at least nine large panels were removed, in some cases for photography reasons. District tests during the three-day event showed that the din from the race registered 93 to 105 decibels in parts of the adjacent Kingman Park neighborhood, far exceeding the city's 60-decibel limit for residential areas.

D.C. Council members, several of whom already had been calling for the cancellation of future Grand Prix events in Washington, reacted with indignation last week upon learning that Grand Prix Holdings supplied the city's consumer and regulatory affairs agency with inaccurate information about who would build the sound wall.

"I think the District government should explore prosecution for perjury or making false statements," said Phil Mendelson (D-At Large).

Concerning the information provided by Grand Prix Holdings, mayoral spokesman Tony Bullock said: "Whoever signed the letter needs to explain to DCRA why it contained information that is not accurate. The mayor expects people to be honest in their applications to the city for any permit."

David A. Clark, director of the consumer and regulatory affairs agency, said the promoter's credibility has been hurt. "Clearly, they made statements that they didn't adhere to. I'm not sure how we can trust what they submit in the future without verifying it."

Robert D. Goldwater, president and executive director of the D.C. Sports and Entertainment Commission, which signed a contract with Grand Prix Holdings to hold the race in the District for at least 10 years, also expressed concern.

In a statement released Friday, Goldwater said the commission had assurances from Grand Prix Holdings that it was fulfilling its obligation to install the sound fence as described in the letter to the city's consumer and regulatory affairs agency.

"We will speak to NGPH about this subject at the first opportunity. The commission is absolutely committed to requiring NGPH to come up with improvements for next year's event," Goldwater said.

Mayor Anthony A. Williams (D) has repeatedly said the Grand Prix is crucial to showing that the nation's capital can stage world-class events. Because of the acrimony the noise caused in Kingman Park, the mayor, Lencheski and the sports commission have said in public forums that they will explore additional noise-reduction techniques for next's year's Grand Prix.

But a half-dozen experts in sound engineering said in interviews that lowering the noise level to within the permissible range will be virtually impossible -- even if a large amount of money is spent.

"The bottom line is that there is no way they can comply with a 60-decibel ordinance. I have never seen more than a 20-decibel reduction in any case from a sound wall," said Ilene J. Busch-Vishniac, dean of the Whiting School of Engineering at Johns Hopkins University.

After the race, Lencheski indicated that earthen mounds might help diminish the noise. Fred Culick, professor of mechanical engineering at the California Institute of Technology, said that a tremendous amount of space would be needed to accommodate that mitigation measure.

"You would have to have earthen mounds as high as the structures you are protecting, maybe even higher, to make it effective," Culick said. Even then, he said, "The problem with that is that sound turns corners. . . . Overall, this is a terrible problem to solve."

Robert Andres, chief executive of Oshex Associates, a noise-control firm near Syracuse, N.Y., said he has studied noise issues at about a dozen auto racetracks and that solutions are elusive. "The reason we have not done a lot of mitigating is because there is very little that can be done," he said.

Unlike Washington, other cities that have hosted street-circuit auto races generally have not staged the events in such close proximity to residential neighborhoods.

After Washington's inaugural Grand Prix, several D.C. Council members said that professional auto racing should never again be held in a residential neighborhood of the city.

Concerned about the council's criticism, sports commission officials have been working the phones and the halls of the John A. Wilson Building to persuade lawmakers to mute their negative remarks and appreciate the value of the race. The commission's top two officials have contended that unfavorably judging the race publicly could jeopardize the Washington-Baltimore bid to secure the 2012 Summer Olympics.

But after learning late last week about the inaccuracies in the promoter's July 2 letter about installation of the sound wall, council members said their misgivings about the sports commission's 10-year contract with the Grand Prix promoter are now even stronger.

Kevin P. Chavous (D-Ward 7), who represents Kingman Park, said credibility issues surrounding the Grand Prix should compel the council to consider whether the sports commission should be restructured through legislation.

Harold Brazil (D-At Large) was more supportive of the Grand Prix, calling it a major boost in terms of economics and visibility for the city. Brazil, chairman of the Committee on Economic Development, said he plans to hold a town meeting to hear from the community, the sports commission and experts about what can be done to reduce the noise and allay residents' concerns.

In his July 2 letter to Clark, Lencheski wrote: "We have been working with George Bittman of Portable Fence Systems [Ltd.] out of Alberta, Canada. They will install a sound-dampening fence along the border of the race track where it passes nearest to the most highly affected residents."

In last week's interview, Bittman, 63, said he was unable to develop and market the test sound wall he built in 1981 because it was too expensive.

Bittman, whose firm's security fences were used at the Atlanta and Calgary Olympics, said he met with Grand Prix Holdings officials in Washington about nine months ago to try to land a deal for the event to use one of his fences. When he toured the race site at RFK Stadium and saw how close it was to homes, he brought up the possibility of designing a sound wall for the race, he said.

He said he had about three subsequent phone conversations with Grand Prix Holdings between February and May of this year about the materials and dimensions of the sound wall.

But he was never able to strike a deal with the promoter for either the security fence or the sound wall, Bittman said.

Yesterday, he said he had received a call from Grand Prix Holdings to apologize for entangling him in the controversy.

Sam Speers, 10, and Evan Coar, 11, both of McLean, try to block out noise from a motorcycle jump by daredevil Robbie Knievel, which preceded the Cadillac Grand Prix of Washington, D.C., last weekend.