Granger Construction continually strives to advance the art of building by reducing the environmental impact of projects. We understand there is a fine line between making choices that preserve natural resources while still meeting the demand for new construction, and one way to do this is by utilizing brownfield sites. These sites have been previously used for industrial or commercial purposes and often contain hazardous waste or pollution. Examples include:
- Decommissioned Factories
- Landfills
- Dry Cleaning Facilities
- Gas Stations
Revitalizing brownfield properties involves many obstacles, which once kept developers and builders from even considering these sites. Challenges range from unstable soil conditions, environmental contamination, hazardous materials, potentially harmful gases given off by the site, liquid wastes that may leach out of the ground and other concerns. However, through new technologies and methods such as Dynamic Replacement (DR) Systems, companies like Granger Construction can overcome such challenges and safely redevelop brownfield sites.
Brownfield Site Development Case Study
Granger Construction was tasked with building a $152 million mission critical data center for a Fortune 500 automotive company over an old foundry sand landfill, creating numerous design and construction challenges. Key design objectives were to:
- Avoid Landfill Disturbances
- Maintain the Environmental Integrity of the Landfill
- Mitigate Landfill Gas Intrusion into the Facility
To meet these objectives, the design-build team extensively evaluated several foundation designs and ground improvement strategies and challenged conventional thinking by implementing multiple innovative solutions.
Dynamic Replacement: The team utilized a ground improvement strategy called dynamic replacement in lieu of traditional deep foundations such as auger cast piles. While it was new in Michigan, the team recognized it offered the best solution to densify the soil and increase its bearing capacity. To provide adequate allowable bearing pressures within settlement tolerances, dynamic replacement “prints” (sized 6’ to 7’ in diameter) were formed by placing a blanket of very dense granular materials over the individual foundation footprint and driving it into the soil by dropping a 15-to- 30-ton weight from a crane into the underlying unsuitable soil. This process densified the underlying soils within the zone of influence of the foundation and compacted the foundation subgrade consisting of the dense graded aggregate.
Vapor Intrusion Barrier: To mitigate landfill gas intrusion, the team designed and installed a vapor intrusion barrier system to keep the landfill gas below ground from leaking into the new building. While chances of that happening were slim, the client and our team were not taking any chances.
Leachate Collection System: The team also designed a leachate collection system to control the level of water coming into the landfill. The system consists of collection piping spanning three-quarters of a mile that taps into an existing discharge point that the client already had permitted. By removing this water, it reduces the amount of contaminated liquid called leachate that is generated from water percolating through the landfill site.
The project team aggressively took on the challenge of building on a landfill, utilized innovative strategies to overcome those challenges and ensured all client and regulatory requirements were met. Their efforts resulted in the completion of a new, 200,000 square-foot, LEED Gold Certified building – providing modern and secure computing and data storage to meet huge increases in the use of technology and software to ensure its products remain competitive. This project is a testament to the fact that redeveloping an unused brownfield property is achievable. By taking more responsibility for where we build, how we build and the materials we use, it is clear we can reduce our carbon footprint within the built environment.
