WithersRavenel’s environmental engineers, geologists and environmental scientists performed a rigorous program of services to help M/I Homes transform a distressed brownfields site into a beautiful new community in Raleigh’s historic Five Points district called the Grove at Fallon Park.
Nestled inside the Beltline in the historic Five Points neighborhood is a 10-acre tract that, since 1952, had served as a bus parking, fueling, and maintenance facility for Wake County Public Schools. In 2012 the school district declared the property surplus and sought to divest it. The school district estimated the sale would net a profit sufficient to offset future costs associated with leasing an office building in Crossroads Corporate Park in Cary, NC.
M/I Homes, ranked the 3rd largest homebuilder in the Triangle and the 14th largest homebuilder nationwide, purchased the property in 2013. They planned a signature community of 83 Energy Star® Certified townhomes. Because the property had previously been used as a fueling center, M/I Homes wanted to take every precaution to make sure that construction workers and future residents would be kept safe. They turned to WithersRavenel, their partner on several other successful projects in Wake County, to provide land development and specialty environmental services for converting the site to residential use.
During a Phase I Environmental Site Assessment (ESA) in April 2012, WithersRavenel noted approvingly that Wake County Public Schools had pursued extensive investigation and cleanup efforts relating to the petroleum underground storage tank (UST) system and the remnants of the maintenance buildings since the early 1990s. Between May and September 2012, WithersRavenel completed a Phase II ESA along with additional investigation activities, including soil, soil vapor, and groundwater assessments. These activities supplemented work completed by Wake County and were necessary to determine whether residential development of the property was feasible.
But although Wake County had obtained site closure letters for each petroleum UST system closure on the property, M/I Homes chose to pursue a Brownfields Agreement for the project. A Brownfields Agreement provides a mechanism for the NC Department of Environment Quality to treat prospective developers of Brownfields sites differently than the parties responsible for contaminating them. It specifies what actions a developer must take in order to make a Brownfields site suitable for reusetypically less stringent than cleaning up the site to regulatory standardsand provides certain liability protection to the prospective developer for pre-existing contamination. It enables and incentivizes developers to reuse abandoned or underused properties rather than seek Greenfield sites.
The data from WithersRavenel’s ESAs became the basis for a successful application to include the property and the proposed residential development project in the NC Brownfields Program. M/I Homes of Raleigh, LLC became the official applicant for the project in February 2013.
Complying with the terms of the Brownfields Agreement would ensure that the property was safe for reuse, but M/I Homes wanted to provide an added level of protection for the residents of the development. In response, WithersRavenel designed an innovative soil vapor mitigation system. This system consists of the first residential application of an aerated floor system using CUPOLEX® in North Carolina.
CUPLOEX® is a system of 100% recycled plastic modules that are linked together to create a custom formwork. Concrete is poured over this formwork to create an aerated floora concrete slab over an under-slab void used for ventilation. An aerated floor is effective at controlling vapor intrusion, humidity levels, and temperature ranges. It also eliminates the costs of importing and compacting the fill or gravel typically required to bring a slab to finished grade, grants maximum control over the concrete curing process to prevent curling or cracking, and provides a ready-made space for running cables and pipes.
Working with the manufacturer, M/I Homes design team, concrete foundation and plumbing contractors, and City inspections office, WithersRavenel spearheaded the integration of the mitigation system design and the development of best practices for this project. Once the system was installed, WithersRavenel performed sub-slab soil vapor mitigation system inspections to verify that the system worked as designed to eliminate any threats from vapor intrusion.
Construction on the first townhome units began in June 2014 and all of the units have now been sold. Where once there was underused and polluted property, there are now scores of families living and enjoying the historic scenery, exceptional schools, and thriving local businesses of Five Points. Because of WithersRavenel’s ingenuity, they do not have to worry for a moment that their health or well-being are at risk.