In the race to bring a Las Vegas-style casino to the Bay Area, a tribe with connections to Lake County is inching closer but still faces significant opposition.

The Scotts Valley Band of Pomo Indians is on the verge of getting its final environmental study approved for a 225,000-square-foot casino near Richmond.

The lengthy document could be finalized by April 29, a key step before a decision is made on the casino proposal.

The 181-member tribe still must convince the U.S. Bureau of Indian Affairs that the 30-acre site on the shores of San Pablo Bay is part of its ancestral territory and should be restored as tribal land.

"We've been working on this 10 years," Tribal Chairman Donald Arnold said. "It's a long process."

He said it is difficult to predict how long it will take to get a decision on the casino or whether it ultimately will be approved.

"I don't know. The government does what it it does, when it wants to do it," he said.

Some Indian gaming critics are concerned that if the tribe gets a green light, it will open the way for other tribes to pick almost any piece of land for a reservation and casino.

"It sets an unwanted precedent," said gaming watchdog Cheryl Schmit, director of Stand up for California. "Tribal gaming could be anywhere."

If the Scotts Valley Pomo are able to get their casino, "I see a snowball effect," she said. "Out of 108 recognized tribes in California, we have 60 rancheria tribes, not all in marketable locations, who would be seeking a better deal."

There was a furor over so-called "reservation shopping" several years ago when four tribes with ties to the North Coast, including the Scotts Valley Pomo, proposed casinos in the East Bay.

The largest one, planned by the Lytton Band of Pomo, would have transformed a former cardroom in San Pablo into a Las Vegas-style casino.

Gov. Arnold Schwarzenegger approved a gaming compact with the Lytton tribe to allow up to 5,000 slot machines, but the Legislature refused to ratify it.

Since then, the Lytton tribe has operated the San Pablo Casino with electronic bingo games, which closely resemble slot machines, but do not require approval from the state.

In mid-2005, the Lower Lake Rancheria in Lake County dropped its proposal for a $200 million casino/hotel complex with 2,000 slot machines near Oakland International Airport.

Still on the drawing board is a 3,000-slot casino proposed by the Ukiah-based Guidiville Band of Indians at Point Molate in Richmond in partnership with Harrah's Entertainment.

The Scotts Valley Pomo application appeared to surge ahead in the regulatory process recently when the Bureau of Indians Affairs said the public had only four more weeks to comment on the massive environmental document -- numbering thousands of pages -- before it becomes final.

The proposed casino has drawn opposition from the Contra Costa County Board of Supervisors, but some observers say local and state opposition may not be enough to sway federal regulators.

"Our concern is that three Nevada-style casinos within a few miles of each other will change the character of the area," said Contra Costa Supervisor John Gioia.

Schwarzenegger has expressed his "firm opposition" to the application by the Scotts Valley Pomo.

When he weighed in on the project several years ago, he said the 2000 ballot initiative that allowed Indian gaming was not intended to lead to widespread urban casinos.

The Richmond City Council, which welcomes the jobs and economic development the project would generate, lent its support in 2006. The council approved a 20-year, $335 million revenue-sharing agreement with the tribe intended to to offset impacts from the casino if it is built.

The BIA still must decide whether the 30-acre North Richmond industrial site purchased by the tribe's investment partner qualifies as Indian land and whether it was part of Scotts' Valley ancestral territory.

Terisa Draper, a supervisor in the BIA's Sacramento office, said Friday that decision is pending in the agency's Washington office.

The tribe argues that its members can trace their lineage to Indians who lived close to San Pablo Bay before they were enslaved, killed and uprooted in the mid-1800s.

In particular, the tribe says their primary, direct ancestors lived in the Carneros Valley in Napa County, 15 miles from the Richmond site.

In 1911, a 57-acre rancheria, later known as Scotts Valley, was established in Lake County where some of those uprooted Indians lived.

The rancheria, like many others in California, was terminated by the federal government in the late 1950s.

Although tribal status was restored by a court in 1992, the Scotts Valley Pomo remain landless. The tribe said that many of its members now live in Contra Costa County and elsewhere in the Bay Area.

You can reach Staff Writer Clark Mason at 521-5214 or clark.mason@pressdemocrat.com