A state appeals court has upheld an L.A. County environmental review for a portion of the mammoth Newhall Ranch community in the Santa Clarita Valley.

The project, called Landmark Village, is a development of the Newhall Land & Farming Co. located south of Highway 126 that includes 1,400 homes, a mixed-use office and retail center and an elementary school.

The county’s 2011 approval of the land use permits and environmental impact report on Landmark Village was challenged in court by a host of environmental groups including the Sierra Club, Friends of the Santa Clara River and the Center for Biological Diversity. In February 2013, a Los Angeles Superior Court rejected the environmental arguments in that lawsuit.

On Tuesday, a three-justice panel of the California Second Appellate District unanimously supported that lower court ruling, finding that the county had acted appropriately in approving the EIR on the project.

The developer applauded the decision. “The appellate decision fully supports the Superior Court ruling and validates the several years of environmental review undertaken by the County of Los Angeles regarding Landmark Village,” Newhall Land spokeswoman Marlee Lauffer said in a prepared statement.

But Dean Wallraff, an attorney with Sunland law firm Advocates for the Environment, which represents the environmental groups, called the appeals court decision unfortunate. “The legal environment in the Second District Court of Appeal is difficult for environmental plaintiffs,” he said.

However, the larger Newhall Ranch development – a total of 20,000 residences and 5 million square feet of office space over more than 2,500 acres – is still fighting the legal challenges that have held up the project for many years. Last July, the California Supreme Court agreed to hear an appeal by the environmental groups challenging an earlier appellate ruling that upheld the environmental report approved by the California Department of Fish and Wildlife. That case has been fully briefed but it has not yet been placed on the Supreme Court docket for argument, Wallraff said.