Situated on a 17-acre former landfill site, the Schoolcraft Public Safety Training Complex consists of four components which can simulate a variety of police, fire, and rescue situations: fire training tower; 10-acre driving course; classrooms with a confined space training maze; and a firearms training range building. A unique partnership between Schoolcraft College and the City of Livonia, the complex is only one of two in Michigan, and among very few in the Midwest.

Early in the project, SME assisted the college with environmental due diligence, Phase II Environmental Site Assessments, Baseline Environmental Assessments and a hazardous materials assessment. SME worked closely with the owner, architect, engineer, as well as SCS Engineers (landfill gas consultant) to develop a design and due care plan for appropriately handling soil and groundwater during construction. Concurrently, SME conducted a geotechnical engineering evaluation that provided recommendations for general site preparation, subgrade preparation, re-use of on-site soils as engineered fill and foundation design. Complete removal of existing fill and replacement with engineered fill was deemed to be cost prohibitive, so the project team opted to build the project on top of the landfill.

Since the driving course was constructed over an existing closed landfill, significant planning and consulting was involved during the design of the stormwater collection system to avoid disturbing the existing landfill gas extraction system and clay cap. SME developed a pavement support system that incorporated lightweight aggregate subbase layers combined with multiple layers of geogrid, covered by hot mix asphalt. The geogrid layers and lightweight fill provided an even distribution of loads and reduced the potential for settlement while the asphalt reduced water infiltration. Rain gardens, drainage bioswales, and other “green” measures were constructed as natural site features to transport surface water to other areas of the property via underground piping.

During construction, SME worked with the contractor and the college with environmental consulting related to soil and groundwater management, and construction materials monitoring and testing related to foundations, concrete, engineered fill, masonry, as well as site work, utilities, and pavements.

To manage groundwater and reduce stormwater runoff into the landfill, SME designed a stormwater detention basin with an impermeable geomembrane liner in the bottom of the pond to keep stormwater from seeping in and exacerbating landfill conditions. Due to a high water table and waste, the floor of the storage basin and its minimum volume requirement was adjusted during construction. To enhance a minimum 2-foot clay cap over the bottom of the basin, SME recommended using flowable fill consisting of a Bentonite slurry trench plug to further prevent seepage of stormwater into the landfill.

Although the fire training tower was located just outside the landfill area, the same fill and landfill gas issues posed design concerns. Because of the building loads, fills, and below grade obstructions, it was decided to support the tower on a mat foundation. SME’s Pavement Team also recommended installing a continuously reinforced concrete pavement since the tower’s burner can reach temperatures of 500 degrees Fahrenheit and create a significant thermal gradient between the upper and lower portions of the slab, leading to the potential for curling and cracking in the slabs.