Opponents of the controversial Koa Ridge development plan reiterated concerns in three main areas yesterday — the needs to preserve prime farmland, prevent the worsening traffic and provide sufficient new schools.

The comments came at the last in a series of Koa Ridge public hearings before the state Land Use Commission.

A few hundred voices, largely in opposition to the project, were added to the record in the case in which Castle & Cooke Homes is seeking approval to urbanize 768 acres of prime farmland between Mililani and Waipi'o for development of 5,000 new homes, a 28-acre medical campus, a 150-room hotel, parks, two elementary schools and nearly 500,000 square feet of commercial space for retail, offices and light industrial businesses.

It was previously anticipated that expert witness and public testimony had been largely concluded at the LUC's April meeting, and that yesterday's meeting would consist of a few rebuttal witnesses and closing arguments by the developer and other stakeholders.

Yet commissioners spent much of yesterday's meeting absorbing more public testimony.

The outpouring of comments from community members reflects a contentious issue at hand — deciding whether O'ahu is at a point where all remaining available prime farmland should be preserved for future food and energy security needs.

Testimony presented to the nine-member commission yesterday included 40 postcards opposing the project mailed after the April 25 hearing, a petition against Koa Ridge containing 220 signatures collected by University of Hawai'i students and 62 written comments.

About 70 e-mailed comments also were received in just the past two days. Testifying in person yesterday were 18 people, including four members of the Legislature.

Castle & Cooke, which developed Mililani, said its plan is appropriate because the land is within the city's urban growth boundary and is adjacent to Waipi'o and Mililani communities as well as 3,700 acres owned by Kamehameha Schools already approved for urban use.

The developer said the urban growth boundary should be respected because it designates where farming should be protected and urban growth directed.

Castle & Cooke also has said Koa Ridge will create jobs and affordable housing. The developer estimates there will be 2,500 jobs in the community — two jobs for every three homes. And it expects the city will require at least 30 percent of Koa Ridge housing, or 1,500 homes, be affordable to households earning from less than 80 percent to 120 percent of Honolulu's median income.

Koa Ridge is proposed to be developed in two phases: one called Koa Ridge Makai with 3,500 homes and most of the commercial space, and one called Castle & Cooke Waiawa with 1,500 homes.

Work on the estimated $2.2 billion project could begin next year and produce initial homes in 2012, if LUC approval can be obtained along with a zoning change from the City Council.

Some people and organizations not tied to the project have testified in support of Koa Ridge, including the Hawai'i Farm Bureau Federation and the Mililani Mauka-Laulani Valley Neighborhood Board. But more testimony has been against it.

Three lawmakers — Rep. Marilyn Lee, D-38th (Mililani, Mililani Mauka), Rep. Ryan Yamane, D-37th (Waipahu, Mililani), and Sen. Michelle Kidani, D-17th (Mililani, Waipi'o) — all said they were concerned with traffic and schools, though they didn't take positions for or against Koa Ridge.

"I understand you have a very difficult choice before you," said Yamane.

"This community is divided on this issue," Kidani said.

Sen. Clayton Hee, D-23rd (Kāne'ohe, Kahuku) and chairman of the Senate Committee on Water, Land, Agriculture and Hawaiian Affairs, said for him the greater issue is preserving prime farmland.

"We're at the point of no return," he said, adding that he wouldn't be testifying against Koa Ridge if it were on less-productive farmland.

Most of the site — 546 of 768 acres — consists of the top two soil grades regarded as prime farming soil, representing close to 5 percent of such high-quality farmland on O'ahu suitable for crops.

The property for many years was used to grow pineapple. Presently, Aloun Farms leases about 325 acres to raise vegetables and seed corn.

Castle & Cooke has committed to relocate Aloun to comparable land in Wahiawā owned by sister company Dole Food Co., and yesterday said it has added an additional 332 acres to Aloun's new site, for a total of 667 acres under a 10-year lease with a five-year extension option.

Rodney Funakoshi, senior project manager for Castle & Cooke, yesterday told LUC members that relocating farm tenants to comparable fallow land should be sufficient mitigation for the loss of farmland.

However, the state Office of Planning previously recommended that Castle & Cooke protect 546 acres of prime farmland elsewhere on O'ahu by encumbering such land with an easement restricting that land to agricultural use forever.

The easement idea originated with the state Department of Agriculture, which opposes Koa Ridge but said that if the LUC approves the project then such an easement should be required.

Hee said the idea of protecting some prime farmland in perpetuity as a tradeoff for paving over an equal amount of prime farmland troubles him because it would contribute to the loss of a valuable and irreplaceable resource.

Castle & Cooke has said that it believes there is more than enough fallow farmland on O'ahu to sufficiently enhance food and energy security, which is limited because of economic factors.

Funakoshi said the company supports agriculture, and intends to submit an application to the LUC later this year to designate more than 546 acres of land it owns elsewhere on O'ahu as "important agricultural land" under a state law passed two years ago.

The IAL law is designed to preserve high-quality ag land for uses allowed under the state's land-use code in return for benefits that include urbanizing up to 15 percent of the amount of land that is protected.

Office of Planning attorney Bryan Yee asked Funakoshi if Castle & Cooke would restrict such land intended for IAL designation to farm use and refuse the 15 percent urbanization benefit. Funakoshi said he couldn't commit to either.

Funakoshi also said IAL designation should not be a condition of Koa Ridge approval because the company believes its relocation of farm tenants is appropriate mitigation.

After Funakoshi's testimony, the evidentiary portion of the Koa Ridge case before the LUC was adjourned.

Parties in the case — Castle & Cooke, the city, the Office of Planning, the Sierra Club's Hawai'i Chapter and Mililani-Waipi'o-Malemanu Neighborhood Board chairman Richard Poirier — have until June 21 to submit written proposals for a LUC decision. Commissioners are expected to craft a final decision later this year.