Los Angeles County Supervisors gave three thumbs up Tuesday to the 1,444-home Landmark Village tract – the first phase of the planned 20,885-home Newhall Ranch “mini city” west of Interstate 5 in the Santa Clarita Valley.

Supervisor Michael D. Antonovich, who represents the area, was joined in the 3-0 affirmative vote by Don Knabe and Mark Ridley-Thomas, while Gloria Molina and current board Chairman Zev Yaroslavsky abstained for unspecified reasons.

The vote was a long time coming for the developer, The Newhall Land and Farming Co., which started planning the housing project in 1996.

In a deja vu of sorts, Tuesday’s action included the approval of a tentative tract map for Landmark Village – something that already happened in 1999 before several unforeseen factors intervened, most significantly the decision to place all of Newhall Land’s future “west side” projects under the umbrella of a single specific plan. That plan was approved in 2003.

Bounded by Highway 126 on the north and Six Flags Magic Mountain on the southeast, Landmark Village spans 263 acres and will include 70 single-family homes, 1,105 multi-family units and 69 mixed-use units – plus an elementary school, park and fire station.

It is also expected to provide 3,700 jobs and add 1 million square feet of space to the Santa Clarita Valley’s commercial and retail inventory.

While providing the county with 60 acres of open space, plans call for moving 7 million yards of earth and removing 65 oak trees including 10 heritage oaks.

Several conditions were placed on the company as part of the approval, said county planner Samuel Dea, including bank stabilization in the Santa Clara River. To keep chloride discharges below 100 parts per billion, a 1.2-acre “demineralization” facility and a 1.6-acre brine disposal well would have to be installed before any building permits are issued.

Local environmentalists told supervisors Tuesday the housing project would harm the river and isn’t needed.

“We believe approval of this project was a mistake,” said Lynne Plambeck of Santa Clarita Organization for Planning and the Environment. “At a time when … tens of thousands additional units are already approved but not yet built, this project presents an unnecessary burden to our community.”

She said the development will add to the area’s air, water and traffic problems.

Dea noted that the One Valley One Vision city-county general plan, which heads to the supervisors for final approval next week, calls for an additional 84,000 homes when the Santa Clarita Valley is “built out” – more than the 33,000 approved-but-unbuilt homes Plambeck cites.

Newhall Land spokeswoman Marlee Lauffer said last week the first Landmark Village homes could be built in 18 to 24 months, but the time frame depends chiefly on the status of active and threatened environmental lawsuits.

Not yet calendared for final approval is the 4,000-home Mission Village, the second phase of Newhall Ranch. Supervisors signaled their intent to approve both Landmark and Mission villages when they approved the two projects’ environmental documents last fall.