Plans to bury Fort Pitt's historic Music Bastion wall as part of Point State Park's $35 million renovation project have sunk to a rocky bottom, according to opponents of the controversial interment.

They say the state's park construction contract allows filling of the 8-foot-deep moat along the wall with concrete, asphalt debris and rock -- a chunky mixture of rubble likely to damage the almost 250-year-old handmade bricks in the reconstructed wall outlining the original fort.

The state Department of Conservation and Natural Resources contract requires only that the contractor compact the fill in eight-inch layers and that a "geotextile fabric" separate the debris from the wall. That thin drape will provide no protection for the fragile brick and could trap water against the wall that would cause damage, according to Michael Nixon, a historic preservation consultant and attorney for the Fort Pitt Preservation Society.

"They're using [the moat] as a garbage pit," Mr. Nixon said. "It's incredible what they're doing and very telling about how they don't care about this site."

The state's renovation plan, sponsored by the Riverlife Task Force and the Allegheny Conference on Community Development, calls for filling in the moat to create a level lawn and more usable concert venue on the "city side" of the 18-acre, 35-year-old park.

Mr. Nixon said that "preservation entombment" -- the reburying of previously excavated historic sites to preserve them for future recovery -- is rarely done, but when it is, it requires use of specific fill protocols that use soft materials, like clays or colored sands, to prevent damage to the resource.

"But none of that is being done here because it's inconvenient to the so-called master plan for the park," Mr. Nixon said. "They've sold the soul of Pittsburgh, cashed it out to make a retail place out of the park."

Similar concerns about the preservation of the Music Bastion were raised over the last few months by the state Historical and Museum Commission, which requested that sand and loam be used to fill the moat around the historic bastion where the fort's buglers played.

"This is an issue that needs to be resolved between the two state agencies," said Laura Fisher, a member of the commission.

"No one has the intention to damage the site, but it's appropriate to raise this issue and appropriate to insist on an answer."

Gene Comoss, DCNR's chief engineer, said the state is aware of those concerns but can't afford to truck in those materials, which would add $300,000 or more to the cost of the park renovation.

Mr. Comoss said the state brought a Pittsburgh-area geological firm to the park yesterday to assess whether the fill material will damage the historic site.

"They've already talked to me and in their opinion our fill won't damage the artifacts," he said. A formal report on the fill material will be made to DCNR early next week.

Mr. Comoss said the department has proposed a "middle ground" approach that would put a foot-thick layer of sand at the bottom of the moat and also against the bastion wall, then fill the rest of the moat with the crushed and compacted materials allowed in the contract.

"That would cost a couple of thousand dollars," he said. "But to spend $300,000, well that's a lot of money and we have to look at alternatives."

Richard Lang, an anthropologist who was crew chief on the excavation that uncovered the bastion in 1953, said the state should renegotiate its contract and do what's necessary to protect the restoration and original materials of the fort.

"They've been saying all along that they planned to protect the fort for future excavation, but there have been no guidelines set up," Mr. Lang said.

"Now the DCNR is scrambling to produce some protocols that would reduce the impact of all this heavy grade stuff it wants to compact in the moat, but it's not following the recommendations of its archeological consultant."

Mr. Nixon said the DCNR's treatment of the nationally recognized historic fort and colonial-era battleground site is a violation of the state agencies' trustee duties under the Pennsylvania Constitution and the state history code.

"It's a battleground where men fought and died," he said, "and to treat it like a dump for demolition debris, old concrete trash cans and pieces of sidewalk and roadway is disrespectful."