Negotiators for Ahmanson Deal Get More Time : Development: The National Park Service is requesting $5,000 a day for lost interest to extend the March 31 deadline.

In a hectic day of negotiations Thursday, the National Park Service granted negotiators a little more time to work out a complex deal to develop a mini-city on Ahmanson Ranch, just west of the San Fernando Valley.

The park service, which has set aside $19.5 million to buy parkland as part of the massive development planned for Ahmanson Ranch, has requested $5,000 a day to extend its original March 31 deadline to close the $1-billion deal, officials said.

Developers have until the end of today to guarantee they will make up for lost interest on the money the park service placed in escrow two months ago, park service Supt. David Gackenbach said.

But Gackenbach said his patience is running out.

“If we give them a two-week extension, that will be it,” he said. “It’s not like we give them two weeks and they come back and say they’re a quarter-inch away, so we give them two more. And they come back and say they’re an eighth of an inch away. They can drag this on forever.”

Although he said he would consider a two-week extension, Gackenbach emphasized that he has not yet set a new deadline.

Approved by the Ventura County Board of Supervisors in December, the Ahmanson Ranch project would build 3,050 dwellings for 8,600 residents in the rolling Simi Hills, along with a 300-room hotel, two professional-quality golf courses and a town center of dozens of shops and government buildings. But the other side of the deal would turn over nearly 10,000 acres of land to state and federal park agencies.

The proposal, which faces nine lawsuits, has been opposed by environmentalists and groups from the San Fernando Valley, just east of the Ventura County line. Valley opponents complain that it will generate tax income for the government of Ventura County, where the project would be located, while dumping large amounts of traffic, and creating other environmental impacts, over the border in the West Valley.

The deal has been delayed because Ahmanson Land Co., developer Potomac Investment Associates and entertainer Bob Hope have not been able to agree on how to split up profits from the project. Hope owns 7,000 acres on three ranches that would become public parkland.

The National Park Service holds the linchpin for the deal, because it is providing $19.5 million to pay Hope for two of his three ranches.

If the park service withdraws its funds, the entire deal could collapse. Yet Hope’s attorney, Payson Wolff, on Thursday refused to pay all the money needed to keep the park service’s $19.5 million in escrow.

Wolff declined to give “appropriate assurances that would guarantee keeping the money in place for an additional two weeks,” said Laura Plotkin, a spokeswoman for the Santa Monica Mountains Conservancy, a state parklands agency that is brokering the deal and would receive about 4,700 acres of the parkland.

Her announcement followed an intense negotiating session between conservancy Executive Director Joseph T. Edmiston and Wolff. Optimistic on Wednesday, Edmiston had predicted he might conclude the long-delayed deal during the lunchtime meeting.

Instead, Edmiston said he will suggest that Gackenbach accept a proposal that excludes compensation from Hope, but still offers financial incentives to keep the money in escrow until Wednesday. That would give negotiators more time to sign a final agreement.

Ahmanson Land Co. President Donald Brackenbush and Potomac executive Fred Maas could not be reached for comment.

But a top Ahmanson executive, Bob DeKruif, told Ventura County officials after negotiations Thursday that “we’re getting closer and closer” to a deal.

Times staff writer Daryl Kelley contributed to this story.