YAKIMA — The Yakama Nation has asked the federal government to halt construction of a natural gas pipeline across southwest Washington’s White Salmon River, saying the project will impair an archaeological site that is culturally significant to the tribe.

The line is being built to replace a small section of a 4,000-mile pipeline, stretching from Colorado to the Canadian border, which has been gradually unearthed since a dam was breached on the river last year.

The company building the line, Williams Northwest Pipeline, of Salt Lake City, said Monday that it consulted with state and federal agencies and with three Native American tribes, including the Yakama Nation, before moving forward with the project and believes it has acted in good faith to follow all required regulations.

The Yakama Nation claims otherwise in recent letters to the Federal Energy Regulatory Commission. The tribe urged the commission to order an immediate halt to construction and asked for the pipeline company to conduct an environmental assessment to determine the potential for harm to the site.

The location of the new pipeline sits in the tribe’s ceded lands, where tribal members retain the right to hunt, fish and gather roots and berries.

The pipeline company and the federal agency are violating laws that protect historic sites, Ruth Jim, Yakama Nation councilwoman said in a statement.

“Current construction cannot be sustained without additional destruction of significant archaeological resources,” she said.

The pipeline, about 26 inches in diameter, had been buried under the White Salmon River. When Portland, Ore.-based utility PacifiCorp breached the dam last year, the stream bed gradually eroded.

At one point, 15 feet of soil cover over the pipeline had washed away, Williams Northwest spokeswoman Michele Swaner said.

“We thought, ‘We could watch this or we could take some action,’ ” she said. “So we got the pipeline out of the river.”

The company hired an independent consultant to examine the area and identified one archaeological site, Swaner said. The Cowlitz and Colville tribes raised no concerns with the report, and the U.S. Fish and Wildlife Service and the Washington state Department of Archaeology and Historic Preservation signed off on the project.

However, the latter group later sent a letter of concern to the federal agency last week.

“We’ve been in frequent conversation with the Yakama. They have expressed that they are unhappy with the findings of the report,” Swaner said. “They don’t spell out exactly what they’re looking at. We want to come to some kind of solution, but haven’t determined their concerns.”

Meanwhile, Swaner said the overhead span that will hold the pipeline should be in place next week, and weather permitting, the new line will be tied into the main line before Christmas.

The White Salmon River winds from its headwaters on Mount Adams through steep, forested canyons to the Columbia River. The 125-foot Condit Dam, which sat about 3.3 miles upriver since it was built in 1913, blocked fish passage for native species of Pacific salmon and other anadromous fish that mature in the ocean and return to rivers to spawn.

PacifiCorp elected to remove the dam rather than install cost-prohibitive fish passage structures that would have been required to relicense it. Environmentalists and recreationists hailed the decision to restore a free-flowing river, which is expected to open up miles of new habitat for fish and is likely to create additional recreational opportunities for kayakers and rafters in a region already known among whitewater enthusiasts.