Wal-Mart has abandoned attempts to create a table-top plateau on the slippery, slide-prone clays of the former Dixmont State Hospital property in Kilbuck, and will not build on or develop the site.

The decision, announced yesterday afternoon by the world's largest retailer, ends a 5¹/₂-year battle that began when development plans were announced and intensified after a massive landslide dumped 300,000 cubic yards of dirt, rock and debris on Route 65 last September.

Wal-Mart said its revised stabilization plan, which it expects to submit to the state Department of Environmental Protection in two weeks, will return the 75-acre site to a sloped version of its pre-development, natural condition that includes trees and vegetation.

Wal-Mart spokesman James Davis said the announcement was made to address many of the concerns expressed by the DEP, elected officials and the public about future development of the site along the Ohio River.

"We've said all along that we were focused on site stabilization and this gets any development questions out of that equation," Mr. Davis said. "We felt this was the right time to do this, and hopefully it will change the tide and end worries about Wal-Mart building there.

"We're saying let's get this done. We're committing resources and working to achieve a stable site."

He declined to say how much the new stabilization plan will cost, how much the company has spent on the site so far or whether it plans to eventually sell the property.

Mr. Davis said permanent stabilization of the still-moving soil on the site could be achieved by the end of 2008, but Wal-Mart will continue to monitor the area for many years. Wal-Mart assumed operational control of the site in March from its original developer, Kilbuck Properties.

Wal-Mart engineers met with DEP engineers Monday to discuss submission of the stabilization plan, but there was no indication at the time that the company would make the announcement it did yesterday.

"Stability of the site has always been the department's singular purpose and priority," said Helen Humphreys, DEP spokeswoman. "We're happy to see that Wal-Mart has chosen to put the safety of the community first. We look forward to seeing their plan."

Ms. Humphreys said Wal-Mart will continue to monitor soil movement and ground-water levels and submit the data to the DEP for daily review.

"We're not done here," she said. "It's important for people to understand the goal is implementation of a permanent stability plan."

The company's new stability plan proposes constructing a steep, 40- to 45-foot tall reinforced soil slope on bedrock about 100 feet from Route 65 where the slide occurred. On top of that Wal-Mart will grade a more gentle slope toward the back of the property where two 25-foot tall walls will be built.

The new plan will eliminate the wide, flat field on top of a 100-foot high wall that was part of a site stabilization plan the company submitted in July and that opponents said preserved the possibility of building a superstore and at least part of the $28 million River Pointe Shopping Plaza.

An engineering report by Communities First!, a grass-roots group formed to oppose the Wal-Mart development, said the tall wall and flat field configuration went beyond what was needed to stabilize the property and were "clearly the first step for developing the site into a shovel-ready parcel for development."

Bob Keir, a leader of Communities First!, which was formed to oppose the Wal-Mart development, said it was about time that the company realized that the site is inappropriate for such a development.

"We are extremely gratified Wal-Mart finally decided to do the right thing," Mr. Keir said. "However the devil is in the details, and we will continue to keep an eye on those details."

While Wal-Mart's announcement was cheered by opponents, Mr. Davis said it will disappoint the majority of people in Kilbuck and surrounding municipalities who wanted to see the superstore built.

"This will be a disappointment to a lot of people in Kilbuck who welcomed our investment in their township," Mr. Davis said. "We made the announcement because it puts this page behind us, but it was difficult because the strong majority of people there supported the project."

Wal-Mart, which operates eight stores in the Pittsburgh area and has plans for additional stores in Penn Hills, Irwin and the East Hills, said it will continue to explore "other opportunities for growth throughout the greater Pittsburgh area."