McMahon & Mann News
Recent Projects of Interest
Bridge Foundation in Steuben County
With a new bridge planned to carry County Route 115 (formerly US 15) over the Cowanesque River near Lindley in Steuben County, the firm was retained to examine the site and prepare a foundation design. That work, done for Bergmann Associates of Rochester involved a review of subsurface conditions as well as foundation design recommendations.
Stream Bank Restoration at Gernatt's Chaffee Facility
McMahon & Mann worked with Gernatt Asphalt Products Inc. and the New York State Department of Environmental Conservation to develop and implement a stream bank restoration plan along Cattaraugus Creek in the Town of Sardinia. Approximately 400 feet of the stream bank along Gernatt's Chaffee Facility required regrading and restoration to protect it from the erosive forces of Cattaraugus Creek.
MMCE studied the fluvial geomorphology of Cattaraugus Creek and conducted hydrologic studies to evaluate the elevation and erosive nature of various storm events. Using this information, MMCE worked closely with NYSDEC engineers and scientists to develop a stream bank restoration plan that protects the bank from erosion while restoring riparian habitat. The design features heavy stone fill at the toe and buried stone keyways at each end to protect the lower slope from scour during channel forming flows. The upper slope is vegetated with plantings of redosier dogwood and sandbar willow trees that will restore habitat along the creek.
Kaleida Health Vascular Center
In Buffalo's expanding medical care and research campus, a new building will be rising at Ellicott and Goodrich streets, near Buffalo General Hospital. When completed it will house Kaleida's new center for the treatment of vascular disease. The site had to be cleared of existing buildings before a major excavation could proceed. McMahon & Mann was retained by the foundation contractor, Herbert F. Darling Inc., to draw the plans for the shoring work, an essential step in the first phase of construction.
West Valley Railroad Line
In West Valley, New York, site of the New York State Energy Research & Development Authority's Demonstration Project, a section of the railroad line leading to the site was undermined by a landslide. McMahon & Mann, collaborating with D'Appolonia Engineers of Monroeville, PA, developed plans to remediate the slope failure and monitor the construction work, which was southeast of Fox Valley Rd.
Old Central Renovation at Oklahoma State
Oklahoma State University engaged Geo-Con to stabilize the foundation of Old Central, the first building constructed on its campus. The University built Old Central near the turn of the last century and used it for classrooms and administration. The building is supported by spread footings bearing on expansive clay and throughout its history, the building has experienced serious foundation movements associated with alternating drought periods and wet seasons. The movements continually damaged the building.
The University addressed the foundation movements as part of a general building renovation. Geo-Con engaged MMCE to design a system to address the foundation movement. Recognizing that the foundation movement was caused by the shrinking and swelling of the expansive clay from moisture changes beneath the foundation, MMCE designed a system to limit moisture changes to the foundation bearing grades. This system includes a cement-bentonite barrier wall that circumscribes the building. A geomembrane was attached to the building foundation wall and the barrier wall to limit underlying moisture changes. The geomembrane lies on the subgrade a few feet below the ground surface. The design also included subgrade drains to collect water that seeped down through the ground and collected on the geomembrane surface.
Environmental Remediation at Former Coal Gasification Plant
Geo-Con was engaged to construct a groundwater barrier wall around a former ConEd coal gasification plant site with groundwater contaminated with phenols and other compounds typical of that process. A tributary to Long Island Sound borders the site. The groundwater barrier included a sheet pile wall, a jet grout wall and a cement-bentonite slurry wall that surrounded the site. Plans included excavation of the contaminated soil inside the barrier wall as part of the site remediation.
Geo-Con engaged MMCE to analyze the stability of the slurry trench since plans called for it to be constructed very close to existing buildings. MMCE analyzed the ground conditions and provided recommendations for constructing the barrier wall in the planned locations. The trench stability was affected by a groundwater level a few feet below ground surface and a loose sand deposit. Construction was complicated by the close buildings and a network of buried utilities that paralleled the trench in some locations and crossed it in other locations.
Anchors Support Bridge During Construction
Backstay anchors were used to support the arch bridge carrying the new US Route 219 over Cattaraugus Creek in Western New York. McMahon and Mann worked with Cornell and Company and the contractor, Cold Spring Construction Corp., to design the backstay anchors which hold up the bridge as it is being erected. Each anchorage consists of a reinforced concrete block supported by steel piles and tied back to the abutment with three high strength steel rock anchors that extend 50 feet into the face of the gorge.
Hudson River Remediation
2009 marked the 400th anniversary of Henry Hudson's discovery of the river which eventually was named in his honor. McMahon & Mann is involved in efforts to clean the polluted areas of the river. In Hudson Falls the firm has been working with Ecology and Environment, Inc. (E&E) to provide geotechnical and environmental engineering expertise and construction oversight for the New York State Department of Environmental Conservation at a PCB cleanup site.
The site, which is underlain by shale bedrock, is the location of a former facility that used PCBs in their manufacturing processes. The PCB plume migrated to the river. Part of the remedial solution is to construct a vertical shaft, approximately 200 feet deep, and horizontal tunnels under the river with vertical drains to collect contaminated groundwater. MMCE and E&E have provided their engineering expertise to the NYSDEC to protect the interests of the general public while continuing the success of the project.
Research for National Academy of Sciences
MMCE is continuing in its role as the lead contractor conducting research for the National Academy of Sciences for the project "LRFD Metal Loss and Service-Life Strength Reduction Factors for Metal Reinforced Systems in Geotechnical Applications." This work has been underway since June, 2006 and involves data collection activities at locations throughout the US, including California, New Hampshire, New York, North Carolina, and Pennsylvania.
A final report for the project is under preparation that will present more than 2,000 individual measurements of corrosion rate, a database for archiving details of performance data, recommendations for service life predictions and LRFD designs considering durability of reinforcements, and recommendations for future testing, sampling and monitoring the performance of earth reinforcements.
At the Podium
Featured at North Carolina Conference
Two engineers from McMahon & Mann were among the featured speakers at the 41st Annual Southeastern Transportation Geotechnical Engineering Conference in Wilmington, North Carolina.
Ken Fishman presented an update on his research assessing metal loss and service-life strength reduction for metal reinforced systems in geotechnical applications.
Mike Mann detailed the firm's work involving rock slope stabilization at Letchworth State Park. In a separate program, Mike reported on the firm's successful work in the remediation of soft sensitive clay using the dry mix method.
At Solid Waste Conference
Mike Mann presented a paper at the annual meeting of the Federation of New York Solid Waste Associations. The meeting was held at the Sagamore Hotel at Lake George.
In a discussion of the West Valley facility, Mike's topic was "Interim Remedial Measure of a Radiological and Hazardous Waste Landfill Utilizing a Groundwater Diversion Barrier Wall and Exposed Geomembrane Cover System."
Highway Geology Symposium
Those attending the 60th annual Highway Geology Symposium hosted in Buffalo by the New York State Department of Transportation, the State Thruway Authority and the New York State Museum heard from four engineers from McMahon & Mann.
Ken Fishman reviewed recent results of his pioneering research into the extent of metal loss found where steel implements have been inserted to stabilize failing slopes.
Mike Mann and Andrew Nichols gave overviews of two slope stabilization problems and solutions at Letchworth State Park. One involved the main access road to the park in the high bridge area and the other discussed use of rock bolting and shotcrete in the Middle Falls area.
Shawn Logan described the usage of a dry soil mixture to stabilize soft earth on both sides of Tonawanda creek in the Amherst-Pendleton areas of both Erie and Niagara counties.
Awards
Honored by US Corps of Engineers
Along Tonawanda Creek near Lockport in Niagara County, the continual failure of a portion of the creek's bank near Minnick Road created a potentially dangerous condition. The firm was retained by the contractor, Hayward Baker, Inc., to develop a plan to remediate the failure. The plan was created and approved and the work completed, all under a contract awarded by the US Corps of Engineers, which specified the use of dry cement to stabilize the banks. When the project was finished the Buffalo District of the Corps was honored for its innovative approach, receiving the Engineering Excellence Award from the Great Lakes and Ohio River Division of the Corps of Engineers. The award cited Hayward Baker and McMahon & Mann for the expeditious planning and completion of the work.
Personnel Notes
Continuing a Family Tradition
Andrew J. Klettke, whose uncle is a civil engineer and whose father and another uncle are both land surveyors, has joined the firm as a civil engineer. He is graduate of Clarkson University, with a graduate engineering degree from Tufts University. He previously spent time as an intern with McMahon & Mann. Immediately after joining the firm, he began assisting on a dam project.