A Jan. 28 article about the National Wilderness Institute misidentified an endangered species. It is the dwarf wedge mussel. (Published 1/30/02)

The plastic milk jug holds just a sample of the black goo that takes up a lot of Rob Gordon's time these days.

Planting the jug on a picnic table near Fletcher's Boat House, Gordon stirs the muck from the bottom to achieve its full, evil-smelling effect.

Picture a streak of this stuff floating in the Potomac River, Gordon says. Then imagine that your own government dumped it, right here in the back yard of the nation's capital, right near Big Eddy, a pool where fish spawn. Not to mention, he says, that the discharges flow through open channels in the C&O Canal National Historical Park.

That's why Gordon and his feisty nonprofit organization, the National Wilderness Institute, have gone to court to stop the Washington Aqueduct's practice of discharging tons of sludge into the river.

"There is just no way that's not bad for fish," said Gordon, 38, executive director and founder of the Alexandria-based organization. "It really is an unbelievable occurrence that this would be acceptable in a national park."

Gordon's National Wilderness Institute sounds like an environmental advocate and talks like one. But, according to other environmental groups, it's nothing of the kind.

"It's a green-scam group," said Jon Marvel, who heads the Western Watersheds Project.

To mainstream environmentalists, NWI is a front for conservatives, ranchers, big business and other environmental foes still smarting over spotted owls and snail darters. Its agenda is to expand individual property rights and weaken the government's ability to intervene on nature's behalf, according to Marvel and others.

"The general rap is, they're a wolf in sheep's clothing," said Jim Dougherty, a member of the Sierra Club's legal committee. Nonetheless, the Sierra Club shares NWI's opposition to the aqueduct's discharges and concern over construction of the new Woodrow Wilson Bridge.

Until now, the tiny $223,000-a-year operation has been little more than a mystery and sometime nuisance to Interior Department officials and mainstream environmentalists. But its most recent work could cause major disruptions in the region.

Nearly a year ago, NWI filed a lawsuit in U.S. District Court in Washington seeking to halt the bridge construction and the aqueduct's long-standing practice of discharging sediment into the Potomac. Both operations threaten endangered species such as the bald eagle, shortnose sturgeon and dwarf edge mussel, Gordon said.

The legal battle is still young, and most officials, speaking privately, doubt that the lawsuit will affect the bridge. Their concern -- and the NWI's legal maneuvering so far -- has focused on the claims against the aqueduct, which has been flushing sediment into the river for more than 95 years.

That bugs Gordon, who has hiked and canoed the wilds in North and South America. He rejects being cast as an agent provocateur, saying his group has taken aim at both the Woodrow Wilson Bridge and the Washington Aqueduct only to protect wildlife.

But he also acknowledged that NWI would be only too happy to hold the bridge and the District's only source of drinking water as hostages to a national debate on a key tool of the environmental movement: the Endangered Species Act.

Too often, the nearly 30-year-old law is selectively enforced and puts the interests of animals above people, Gordon said. "I don't think a law can be successful or conservation can work if you make enemies of people," he said.

Rep. George P. Radanovich (R-Calif.), who has taken up NWI's crusade, said that ultimately he wants to force Congress to rewrite the law. And if it takes a federal judge halting work on the Wilson Bridge to make that happen, so be it.

U.S. District Judge Thomas F. Hogan last year declined to take any action that would stall construction of the $2.4 billion span. He also refused to enter an injunction halting the aqueduct's discharges, noting that they have been going on for more than 10 years. In either case, the NWI had not shown actual harm to any endangered species, the judge ruled.

But Hogan, in his rulings, also signaled impatience with the aqueduct's practices and urged the federal government to explore alternatives.

The aqueduct, operated by the U.S. Army Corps of Engineers, draws water from the Potomac to supply about 1 million customers in the District, Arlington County and Falls Church.

As part of the treatment process, tons of sediment are chemically removed and collected in six holding basins -- four at the Dalecarlia Water Treatment Plant and two in Georgetown. Those are emptied periodically into the river at outflows, about a quarter-mile upstream from the Chain Bridge and about a half-mile downstream from Fletcher's Boat House.

The Environmental Protection Agency, which has allowed the discharges since 1989, is drafting a new permit.

Aqueduct chief Thomas P. Jacobus declined to be interviewed because of the litigation, a Corps of Engineers spokesman said. But the Corps of Engineers has argued that the silt going into the river is virtually the same silt that came out of it. Two scientific studies commissioned by the Corps of Engineers have shown that the discharges have a negligible impact. And no one has found shortnose sturgeon or dwarf edge mussels within 40 miles of the discharges, the Corps of Engineers says.

However, if the NWI wins in court, the aqueduct might have to truck the sludge through District neighborhoods to a landfill or build a $60 million sludge-handling facility.

All of which points up how unevenly the government enforces the endangered-species law, according to the NWI and its backers. They say it is seldom enforced in urban areas, such as Washington, but is strictly enforced in the West.

"My view is if it were applied in urban areas -- where there are plenty of endangered species -- the population wouldn't stand for it," said Radanovich, former chairman of the Western Caucus.

Federal agencies always seem to look the other way on projects such as the Wilson Bridge and situations like sludge from the aqueduct, Radanovich said.

Enter Gordon and the NWI, whose advisers include Radanovich, Rep. Don Young (R-Alaska), Sen. Larry E. Craig (R-Idaho) and Becky Norton Dunlop, a former Virginia natural resources secretary. The goal of NWI, say its promoters, is to shift the environmental debate by emphasizing incentives and market-based solutions rather than regulation.

Since its founding in 1989, NWI has seldom gone to court. Gordon said he prefers to promote his views through research, publications and other activities.

This time, however, Gordon said he had no choice but to take legal action. The U.S. government, in court papers, questioned NWI's motives -- and even Gordon's description of members as "conservationists."

But Gordon, who said he has learned about the natural world by indulging his passion for the outdoors, said he simply wants a more workable law.

The sight of a bald eagle just south of Old Town Alexandria got him thinking about taking action against the Wilson Bridge, he said. Then he learned about the aqueduct's discharges and went to court.

"We're different. We have a unique message," Gordon said. "A lot of ideas that we put out when we first started out are becoming mainstream."

Metro researcher Bobbye Pratt contributed to this report.

Robert Gordon and his nonprofit, the National Wilderness Institute, have gone to court to stop the Washington Aqueduct's practice of discharging sediment into the Potomac.