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November 10, 2005Septage repairs outlinedTank building must be rebuilt, firm saysTRAVERSE CITY - One concrete tank building and possibly more will have to be completely rebuilt at Grand Traverse County's failed septage treatment plant.Meanwhile, the laundry list of missing and misplaced steel continues to grow. In a presentation Wednesday afternoon, the county's engineering consultant said construction errors and omissions "significantly weakened" the strength of the walls and floors in three buildings designed to hold hundreds of thousands of gallons of sewage. "It's a lack of quality assurance," said engineer Chris Campbell of NTH Consultants. "When they tie the steel and before they pour the concrete, there should have been an observer out there to make sure it's right." One of the walls collapsed in June, releasing 150,000 gallons of partially treated sewage. NTH said the collapse was caused due to missing steel hooks that were supposed to tie the wall to the roof. The facility was constructed by the design-build firm of Gourdie-Fraser/Christman LLC. Gourdie-Fraser Inc. of Traverse City engineered the facility and the Christman Co. is the general contractor. The two companies originally proposed to rebuild just the wall but now will tear it down and start over with plans approved by NTH. Campbell said NTH wants to be on the site during deconstruction to determine whether there are more flaws not visible in X-rays. Campbell said that conceptually, the other tanks can be repaired, but that could change if more problems are detected. "As the laundry list grows longer and longer, there will have to be a decision made based on cost," he said. East Bay Township supervisor Glen Lile, a member of the county's sewer and water committee, asked if any of the walls were right. "I believe I can probably find one," Campbell said. "In general, we found problems with most of the walls." Steel hooks that were supposed to tie a common dividing wall to the outside walls of the tanks were missing. In several areas of the foot-thick, poured-concrete walls, the steel was too close to the inside wall. In the floors, NTH found the steel at the bottom of the slab, making it "useless," Campbell said. "I've been genuinely surprised by the level of problems," said Scott Jones of the Christman Co. Jones said he still intends to use the same subcontractor, Farrington Construction, to rebuild and repair the concrete walls but with increased inspections. County attorney Michael Houlihan said he's been told Farrington's engineer claims design problems also contributed to the collapse. The buildings were designed by Gourdie-Fraser to a standard for concrete buildings known as ACI 318 instead of the industry standard of ACI 350 for wastewater treatment plants, Campbell said. ACI 350 uses more steel to control cracking and leaks. "With ACI 318, it would have had water tightness and crack control issues but it certainly wouldn't have fallen down," he said. Campbell said it's rare for such a facility not to be constructed to ACI 350 even though building to ACI 318 is "absolutely" cheaper. "The only one I'm even aware of is right here," he said. See Related Stories: Consultants to offer final septage report - November 9, 2005 Subcontractor questions collapse fault - November 4, 2005 Septage report cites company's omission - October 19, 2005 Acme wants Houlihan removed from investigation - October 15, 2005 Septage plant collapse explanation coming - October 15, 2005 County officials back Houlihan in septage investigation - October 7, 2005 Septage 'debacle' questioned; Supervisor wants all info - October 4, 2005 Public awaits report on collapse of septage plant - September 27, 2005 Taxpayers won't foot bill for septage plant repairs - July 26, 2005 Officials looked for 'spin' in septage plant collapse - July 23, 2005 Septage spill situation becoming muddled, attorney says - July 23, 2005 Septage plant repairs tagged at $2 million - July 19, 2005 Health risk from septage plant failure said minimal - July 19, 2005 Well owners near septage plant fear contamination - June 25, 2005 GT County's septage treatment plant may reopen - June 22, 2005 Septage plant 'structural failure' is investigated - June 21, 2005 Burst tank rocks GT County's new septage plant - June 19, 2005
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