LOS ANGELES (CBS) — The Metropolitan Transportation Authority Board of Directors Thursday approved plans for the first phase of a $5.6 billion extension of the Purple Line subway toward the westside, but delayed action on the next two segments so it can consider objections to a tunnel under Beverly Hills High School.

KNX 1070’s Vytas Safronikas reports the board approved a roughly 3.9-mile extension of the so-called “Subway to the Sea” from Wilshire Boulevard and Western Avenue to La Cienega Boulevard and Wilshire.

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Beverly Hills city and school district officials, however, requested a formal hearing on plans to tunnel under the high school, so the board opted to postpone action on the extension of the subway to Century City and Westwood until that hearing can be held.

Beverly Hills Mayor William W. Brien said that while residents of the city are “enthusiastic supporters” of the subway extension, they object to tunneling beneath “the historic core of Beverly Hills High School,” which may “preclude future construction” at the campus.

Councilwoman Lili Bosse said she also supports the Westside extension, but wants Metro to closely study the proposed tunnel below BHHS.

“It’s been a very emotional issue, and I do believe we all want the same result,” she said. “We all want better public transportation.”

Citing earthquake risks and ridership data, Metro recommended a Century City station at Constellation Boulevard and Avenue of the Stars over an alternative stop at Santa Monica Boulevard and Century Park East. The selection means the subway would have to travel under a portion of BHHS.

Beverly Hills city and school district officials have disputed Metro’s seismic studies and said building the station at Constellation Boulevard would be more expensive.

“We only ask all of the science available be reviewed,” Beverly Hills Councilman Barry Brucker said.

But County Supervisor Zev Yaroslavsky, a member of the Metro board, insisted there are subway tunnels built under courthouses, homes, schools and businesses elsewhere that have caused no problems.

In any case, he said, the start of construction near the Beverly Hills campus is “a long way off.”

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“There is room to talk and room to make this work for everyone concerned,” Yaroslavsky told the crowded meeting hall.

He added that the westside is a major destination point for people from throughout the Southland.

“People will be coming from all over the region because the westside — for better or for worse — has become a major employment center,” the supervisor said.

Yaroslavsky warned that if the subway extension did not feature a Century City stop, it would be a mistake of historic proportions. Such an error, he said, would be “added to the list of mistakes” such as not linking a rail line to Los Angeles International Airport and failing to build a Red Line stop at the Hollywood Bowl.

He also said that if the issue was going to lead to a court battle with Beverly Hills, “let’s get that started now …. because the sooner we can begin construction, the sooner we can bring traffic relief to this region.”

In the first phase of the extension, the train will stop at La Brea and Fairfax avenues and La Cienega Boulevard. Future segments would take the train south toward Century City, then west, with stops on Wilshire near UCLA and the Veterans Administration hospital just west of the San Diego (405) Freeway.

When complete, riders would be able to travel from downtown to Westwood in 25 minutes, according to Metro officials, who predict an average 49,300 weekday boardings.

Draft environmental documents put the cost at $4.36 billion in 2009 dollars. The final documents calculate the projected cost using the estimated value of the dollar in 2022, when the first phase is scheduled to open.

The subway route does not go all the way to the coast — although it is often dubbed the “Subway to the Sea.”

Metro hopes to break ground on the extension by the fall of 2013.

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