By Pat Jenkins The Dispatch Landslides will still happen, but they shouldn't be a problem any more for people traveling on State Route 7 in the Alder Canyon area now that a permanent containment wall has been built. That's the word from state Department of Transportation (DOT) officials following the earlier-thanexpected completion of the wall made from pilings and timbers at a cost of nearly $1 million. Rocks and other debris that tumbled from a hillside onto the two-lane highway periodically in recent years threatened the safety of motorists and caused temporary closures. After a lengthy study by DOT geotechnical engineers, including electronic monitoring and tests of the slope, officials designed a wall and hired Scarsella Brothers, a Kent-based company, to build it. While the hillside remains unstable, its castoffs should stay behind the new barrier, officials said. "The slides won't stop, but the wall can hold back a large amount of debris,GÇ¥ said Jan Deffenbacher, the project engineer for DOT. When it's time to remove a buildup of rocks and earth, highway workers will be able to remove sections of the wall to get to the stuff and haul it away. A five-mile stretch of highway near La Grande was closed early in July for what DOT expected would be a five-month construction project. But a long, dry summer enabled Scarsella and its sub-contractors to finish the work and reopen the highway Oct. 5, nearly two months ahead of schedule GÇô much to the delight of drivers who no longer had to take detours on their commutes or on trips to Mount Rainier National Park. The early completion "caught us by surprise,GÇ¥ said Deffenbacher. He noted that workers boring through the rocky terrain with massive drills to create holes for the steel piling supporting the wall finished "faster than we thought. We weren't expecting that, because we knew the work would be a challenge.GÇ¥ Part of the challenge was the safety of crews working beneath a hillside with a history of not staying put. Using electronic monitoring devices placed in the slope, DOT engineers could remotely keep track of any shifting and whether the potential for slides was increasing. "It was definitely a hazard,GÇ¥ Deffenbacher said. "There was always a chance of debris coming down. There were regular safety meetings for the workers to remind them of precautions. But we got through it with no injuries or serious incidents.GÇ¥ Among other work, 30 support piles were sunk up to 12 feet deep. The contract for the total project was for $950,000. Last May, after one of the last slides, 300 cubic yards of rocks and debris were removed from the highway. With those days apparently over, drivers once again are cruising through the stretch of highway that has a speed limit of 50. The only time they could do that during the summer was one weekend in August and one weekend in September, when the highway was opened temporarily to accommodate heavy traffic for the Morton Loggers Jubilee and the Labor Day holiday, respectively. A spokeswoman said DOT thanks motorists, businesses and residents affected by the closure and along the detour route "for their patience and toleranceGÇ¥ during the closure.
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