Final Cleanup of Ordnance in Tierrasanta Set : Military: Environmental firm will comb 1,600 acres for live explosives to ensure that no one else is killed by live shells buried on former WWII artillery range.

Seven years after two boys were killed by an artillery shell that exploded when they were playing in a Tierrasanta canyon, officials are launching the final phase of a cleanup that has become the largest of its kind.

The Army Corps of Engineers recently awarded a $4-million contract to a Lexington, Ky.-based firm, Environmental Chemical Corp. The firm, which has moved its offices to San Diego, will comb 1,600 acres for live explosives in a 30-month sweep expected to be finished about April, 1993.

“The aim here is to protect human lives,” said Bob Nore, Army Engineers project manager for the Tierrasanta canyon. “We are concerned enough about it to want to go in and clear it.”

Although applauding the action, local residents say the government years ago should have scoured the land, once used as an artillery range, before turning it over to developers.

“This is something that should have happened 20 years ago, when the government first sold the property,” said Jim Madaffer, chairman of the Tierrasanta Community Council. “Tierrasanta has been a guinea pig. Hopefully, no other community is going to have to wait so long. Hopefully, no other community is going to have to suffer the loss of life before something happens.”

In 1983, two 8-year-old boys--Corey Alden Peake and Matthew Smith--were killed while playing with a military artillery shell that exploded. The boys, with a group of their friends, were building a fort when they came across the shell.

Matt’s mother, Suzanne Gillick-Pew, received a phone call telling her there had been an accident in the canyon.

“I really thought he’d been hit by a car maybe, or fell out of a tree,” she told The Times in an interview at the time. “When I arrived, Matt was already in a body bag. I asked to see him, and they wouldn’t let me.”

The cleanup sweep will cover 1,600 acres, 1,200 publicly owned and 400 Navy-owned. The area will be defined by California 52, Interstate 15, Friars Road, and the San Diego aqueduct. Some of the land hugs private residences, and work will start in those areas first, said Judy Wilson, a spokeswoman for the Army Engineers.

Even after the final phase, the land will not be completely risk-free, experts caution.

“I don’t think we could ever say any area that had ordnance in it could be completely, 100% safe,” Nore said. “But we can make it safe to the best of our knowledge and abilities.”

As the land erodes, explosives buried long ago gradually creep to the surface. In fact, ordnance is found monthly--though most is not live, Madaffer said. Nore and others believe that much of what remains in the soil will be uncovered in this final cleanup.

But Don DeSisto, an attorney who sued the city and developers on behalf of the Peake family, said: “If I were living in the area, I’d be really concerned about my kids playing in open spaces. I don’t know that they can get all that stuff.”

In the years since the boys’ deaths, the Navy has orchestrated several sweeps of the area. In 1984, 178 pieces of ordnance were found; in 1985, 215 were uncovered, said Jeanne Light, a spokeswoman for Southwest Division Naval Facilities Engineering Command. In those two sweeps, which involved masses of enlisted men walking through the canyons and cost $76,000, 100 rounds of ammunition, most of it live, were found.

Last year, during another sweep from June 12 to Aug. 1, 41 items were found--four were deemed unexploded “high explosives,” Light said. That sweep, in which 383 acres of roads, paths and trails were electronically monitored, cost the Navy $95,000, she said.

Tierrasanta, a community of condominiums and single-family homes, was constructed in the 1970s. It sits in an area that had served as an artillery range for the 43-square-mile Marine Corps Camp Eliott during World War II. The land was later transferred to the Navy and to developers.

Two years ago, the city of San Diego and developers agreed to pay $6.3 million to the families of the boys. Signs warning of possible live ordnance have been posted.

Under federal law, the Department of Defense is authorized to restore former and active military sites. And the Huntsville, Ala.-based Army Corps, which is responsible for implementing the DOD’s Defense Environmental Restoration Program, has been preparing a cleanup plan for Tierrasanta. Besides looking for explosives, the experts will have to work carefully, avoiding the nesting habitats of two endangered birds--the black-tailed gnat catcher and the least Bell vireo.

First, the Corps of Engineers conducted a $600,000 feasibility study of the area in 1987. It prepared a contract and solicited bids--a process that cost another $300,000, Nore said. Finally, last month, ECC was awarded the contract for scouring Tierrasanta.

In a press conference Tuesday, officials expect to unveil details of the cleanup. The actual work will begin in November, when teams of workers will sweep the entire 1,600-acre area on foot. The workers will “cover every square inch of surface” to find any ordnance, Nore said.

Next, the teams will clear the brush to allow magnetic detectors to be brought into the area for a “subsurface” sweep. During this process, the detectors will uncover ordnance buried as deep as 3 feet. Studies found that 95% of the materials discovered in the area were within 6 inches of the surface, Nore said. The other 5% was found within the top 3 feet.

“So we are reasoning that, if we go to 3 feet, we are going to have a very clean site,” said Nore, who added that officials expect that most uncovered materials will not be hazardous, or explodable.

Although the Corps of Engineers routinely cleans artillery ranges, this will be the first time that experts have worked on a range that is being used for housing, he said. “Other times, the aim was to clear up a mess--not saving lives.”

Once the final phase is over, the community will keep the warning signs posted. But there will be one change, said Madaffer of the Tierrasanta Community Council. The small sign cautioning that the area has not been swept for live ordnance will be removed.