Precise Site Investigations Proactively Reveal Redevelopment Risks

Even well-documented brownfield redevelopment sites can conceal costly surprises. Former industrial and commercial sites, while attractive investment opportunities, carry layers of environmental history that can complicate redevelopment planning.

The legacy of improper waste disposal combined with historically unregulated materials makes precise site investigation essential. The more accurately a site’s conditions are characterized upfront, the more efficient developers and municipalities can allocate resources, sequence remediation activities and avoid unanticipated project adjustments (and costs) later in the redevelopment process.

Former industrial activities don’t always leave clear records, making it difficult to pinpoint historical waste locations or the full extent of fill areas. In many cases, underground storage tanks, abandoned utilities and buried debris may also remain in place long after facilities cease operations. Materials used within older structures, including paints, caulks and sealants, may also contain now-regulated contaminants that require specialized handling and disposal.

When these conditions surface late in redevelopment, project teams must often pause construction, revise remediation plans and adjust project budgets.

The most effective way to reduce these disruptions is to improve the quality of early investigation. Tools such as LiDAR mapping, geophysical surveys and targeted material characterization provide a clearer understanding of surface conditions, subsurface anomalies and legacy building materials before construction begins. When investigators apply these tools during phase II environmental site assessments, they detect hidden liabilities sooner, plan remediation more effectively and avoid costly project adjustments .

Traditional site investigations rely heavily on historical documentation, visual inspection and targeted sampling. While these approaches remain essential, they could leave gaps in complex redevelopment sites where decades of land use have altered the landscape.

Advanced investigation tools help close these gaps. Using surface mapping and subsurface geophysics, project teams can develop a more accurate understanding of site conditions before construction begins. Two technologies are especially valuable in modern brownfield investigations.

On complex brownfield sites, subtle variations in topography can signal legacy waste areas, deteriorating landfill caps or drainage pathways that could indicate contaminant flows. These features are not always apparent through standard visual inspection.

LiDAR (Light Detection and Ranging) is a remote sensing method that uses pulsed laser light to measure distances and generate high-resolution, three-dimensional mapping of a site’s surface conditions. By analyzing a detailed LiDAR dataset, our team can identify irregularities in grade, vegetation stress patterns and land cover changes that may warrant further investigation.

In remote or overgrown areas where historical records do not clearly document disposal activities, LiDAR helps our team delineate landfill boundaries and pinpoint areas of contamination concern.

With this information, stakeholders can incorporate stabilization, targeted sampling or design modifications into the redevelopment plan, rather than addressing them after construction begins.

Beyond contamination concerns, LiDAR-derived spatial data also supports grading design, stormwater management planning and infrastructure layout, improving coordination between environmental and civil engineering teams.

While surface mapping enhances visibility above ground, geophysical surveys extend that clarity below the surface. Our team employs ground-penetrating radar (GPR) technology to locate buried waste, underground storage tanks, metallic debris and other subsurface anomalies.

GPR sends radio wave pulses into the ground. When the waves encounter subsurface materials with contrasting dielectric properties, they reflect to the surface, allowing investigators to map buried objects or changes in underground conditions. This tool provides a non-invasive way to assess subsurface conditions across large areas with minimal disruption to site operations.

In one instance, it was believed that an underground storage tank had already been removed, but no record of the removal existed. Surface inspections also showed no visible evidence of a tank. However, a geophysical survey confirmed the tank’s continued presence beneath a sidewalk, helping the team adjust the redevelopment plan and address the issue proactively.

Environmental site investigations don’t end at the ground surface. Buildings constructed before more recent environmental regulations existed may contain materials that require specialized management during demolition or renovation.

Material characterization provides the data needed to manage these risks proactively. One of the most common and consequential examples includes polychlorinated biphenyls (PCBs).

Manufacturers widely used PCBs in building materials between 1950 and 1979 before the U.S. Environmental Protection Agency (EPA) banned their production and use in the Toxic Substances Control Act of 1976. Standard asbestos and lead-based paint surveys often overlook PCBs, leaving owners exposed to unexpected contamination and compliance challenges.

Proper material characterization is crucial to mitigate risks and regulatory complications as debris with high concentrations of PCB must be managed as hazardous waste, according to EPA regulations. We recommend taking the following steps:

• Bulk sampling of suspect materials
• Additional sampling when PCB concentrations range between 1 and 50 parts per million (ppm) to determine the full extent of impacted materials
• Comprehensive testing when PCB concentrations are above 50 ppm to determine if hazardous waste requirements apply

Early characterization supports informed demolition planning, appropriate waste separation and coordination with permitted disposal facilities.

Organizations that fail to properly identify and dispose of PCB-impacted construction and demolition debris risk sizable financial penalties, legal consequences and costly cleanup actions (potentially millions of dollars in penalties and cleanup costs). By proactively characterizing, separating and disposing of PCB-containing materials at permitted facilities, project teams reduce liability and avoid unnecessary remediation expenses.

The value of early material characterization becomes clear in redevelopment projects where demolition and remediation occur in tandem. A brownfields redevelopment project in Vermont illustrates how proper PCB characterization and a thorough site investigation can reduce waste, manage disposal costs and keep complex projects moving forward.

During the revitalization of the historic 1916 St. Johnsbury Armory, Onterris identified multiple regulated materials, including PCBs, asbestos and lead-based paint, within the existing structure. By implementing disciplined material characterization and maintaining strict separation across ten distinct waste streams, the team minimized the volume of PCB-impacted debris requiring hazardous disposal. This approach allowed demolition and remediation to proceed efficiently while preserving the building’s historic façade and supporting the community’s plan to transform the vacant landmark into a modern public service hub.

The success of brownfield redevelopment increasingly depends on the precision of early site investigation. Developers and municipalities that prioritize comprehensive, technology-informed investigations position themselves to manage risk proactively, allocate capital more efficiently and maintain greater control over project timelines.

For developers and municipalities evaluating brownfield redevelopment opportunities, several practices can significantly improve project predictability.

Integrate advanced investigation technologies early in due diligence.
Incorporate LiDAR and geophysical surveys at the front end of site assessment to identify surface and subsurface conditions before design and construction plans advance too far.

Expand material characterization beyond standard surveys.
Include targeted PCB sampling as part of pre-demolition planning, particularly for structures constructed or renovated between 1950 and 1979. Early characterization supports appropriate waste management planning and reduces the potential for mid-project adjustments.

Align environmental data with redevelopment design.
Use high-resolution mapping and subsurface data to inform grading, infrastructure placement and stormwater design. Coordinating environmental and engineering teams around shared datasets improves efficiency and reduces rework.

Prioritize predictability over reaction.
Treat investigation as a strategic investment rather than a regulatory checkbox. More complete data at the outset enables better budgeting, clearer risk allocation and more confident stakeholder communication.

For projects with complex environmental histories, early consultation with experienced environmental engineers can help clarify site conditions and support more predictable redevelopment outcomes. In doing so, they not only meet regulatory requirements but also create a more stable foundation for sustainable, cost-effective brownfields redevelopment.