Fresh off their approval in February of the first 1,444 homes, Los Angeles County’s supervisors will consider granting final approval to the the larger, 4,055-home Phase 2 of Newhall Ranch at their meeting Tuesday.

Newhall Ranch is the eventual 20,885-home “mini-city” being developed by The Newhall Land and Farming Co. west of Interstate 5 in the Santa Clarita Valley.

Phase 2 is called Mission Village and would feature 3,704 multi-family dwelling units plus 351 single-family houses, more than 1.5 million square feet of commercial space, 27 acres of parks, an elementary school, library, fire station and bus transfer station.

Included among the 693 acres of open space are three separate areas designated for the protection of the San Fernando Valley spineflower, a state-listed endangered species.

The project calls for the grading of 58 million cubic yards of dirt and the removal of 143 oak trees, including eight heritage oaks. A necessary extension of Magic Mountain Parkway, outside of the project area, would result in the removal of an additional 11 oaks (three heritage).

Mission Village is bounded on the north by Travel Village at Highway 126; on the east by the Magic Mountain theme park, on the south by Valencia-Westridge, and on the west by the future Landmark Village.

Full build-out of Mission Village wouldn’t occur until 2021, according to a county staff report.

As a whole, the Newhall Ranch development is required to have its own wastewater treatment facility, but it doesn’t have to start building it until the 4,000th home is permitted and it doesn’t have to be operational until the 6,000th home is permitted. Until that time, it must send its wastewater to the existing treatment plant in Valencia and build a 1.2-acre demineralization facility and a 1.6-acre brine disposal well so that chloride discharges don’t exceed 100 mg/l.

Mission Village and the other four phases of development were included in the Newhall Ranch Specific Plan, which the supervisors approved in 2003.

Since that time, a number of things happened to delay development, including a bankruptcy reorganization of Newhall Land, a recession, several environmental lawsuits and intervention by state and federal agencies that regulate encroachment on the Santa Clara River.

Some of the litigation is ongoing. The Arizona-based Center for Biological Diversity and other environmental groups filed another lawsuit challenging the supervisors’ approval of Phase 1, known as Landmark Village. The same groups are expected to challenge any approval of Mission Village that might be forthcoming Tuesday.

Approval is likely. The supervisors indicated their intent to sign off on the project last October when they voted to certify the necessarily environmental documents.