PROVIDENCE, R.I. – The company that plans to build a liquefied natural gas facility in Fall River, Mass., said two recent studies predicting the project would cause major traffic backups and hurt Rhode Island’s marine economy were flawed.

Ted Gehrig, president of Weaver’s Cove Energy, sent a letter dated Thursday to the Aquidneck Island Planning Commission, which commissioned the reports on the project’s effects on traffic and marine navigation in Narragansett Bay.

“Unfortunately, the reports are based on fundamentally flawed assumptions and analysis that render the conclusions invalid,” Gehrig wrote in his letter to Tina Dolen, executive director of the commission.

The letter is the latest move in a back-and-forth volley between opponents of the terminal and Weaver’s Cove, which is owned by Hess LNG. Weaver’s Cove says New England badly needs more capacity for LNG as its energy needs grow. Opponents say LNG is too dangerous to store or move in large amounts through such a densely populated area.

The commission, a regional group for the cities of Middletown, Newport and Portsmouth, has not taken a position on the proposal, but all three communities have joined the legal fight to oppose it.

The marine report, prepared by Pare Engineering Corp. of Lincoln, said a security zone required around supertankers carrying LNG to the terminal would close Newport Harbor for at least 20 minutes each time a tanker passes. Because multiple trips are planned every week, the report said boating in the area would be disrupted, possibly resulting in the loss of Tall Ships festival and cruise ship traffic, a blow to the state’s tourism economy.

The report said the security zone would extend two miles ahead, one mile behind and 3,000 feet on both sides of the ship, a little more than half a mile.

But Gehrig said the zone would only have to extend 1,500 feet on either side because the Coast Guard studied the area and determined such a large zone wasn’t needed, significantly reducing the impact on recreational boating.

“The 3,000 feet isn’t really applicable in this case,” Gehrig told the AP.

Dolen said late Friday that while she appreciated Weaver’s Cove’s position, “the basic construct remains correct,” adding that the security zone was the only one enforced.

“There is no other plan promulgated,” Dolen said.

Gehrig also said Pare Engineering should have looked at Boston Harbor, where LNG tankers routinely travel 10 miles to a facility in Everett, Mass., with a security zone identical to the one proposed for Narragansett Bay. He said cruise ship traffic has grown, and marinas have expanded.

A message left with Pare Engineering was not immediately returned.

But Attorney General Patrick Lynch and others who oppose the project have said that the Everett terminal is not a good comparison because the route through Boston Harbor, which Lynch said was closer to 6 miles, is much shorter than the 23 miles ships must pass through Narragansett Bay.

“This is absolutely apples and oranges,” Lynch told the AP on Friday.

Gehrig’s letter also took issue with the traffic study, prepared by The Louis Berger Group, Inc., which predicted traffic disruptions of up to 47 minutes when tankers pass because bridges will be shut down.

Gehrig cited an order by the Federal Energy Regulatory Commission, which in June gave the green light to plans for the Fall River terminal. The order said it is not necessary to close bridges while tankers pass under them unless there is a heightened terrorism warning level.

The Rhode Island Turnpike and Bridge Authority, however, has ordered that the Newport and Mount Hope Bridges be closed when any LNG tanker is near or under either bridge. Gehrig said the decision was made on the agency’s own initiative in the face of broader, expert opinion that it was not necessary to close the bridges.

He speculated that the decision was a political move to create predictions of traffic nightmares.

“The longer the backup is,” he said, “the easier it is to get the press’ attention.”