Site Investigation, including Drone Deployment, for Property Redevelopment

drone view of site
monitoring well install
drone flight control
drone view of site


The client, the Pennsylvania Department of Environmental Protection (PADEP), required an extensive site-wide soil investigation to develop a plan for site remediation to reuse this former landfill and scrap yard property as a public park. Constituents of concern included polychlorinated biphenyls (PCBs); metals, such as arsenic and lead; and petroleum compounds 

GES Solution

PADEP contracted GES to complete site investigation activities, including surface-soil sampling/screening, aerial photography/mapping, vertical soil investigation, monitoring well installation, groundwater monitoring, and report preparation to assist in moving the site forward to remediation and reuse as a public park.

Prior to initiating the soil sampling activities, GES completed a small, unmanned aircraft system (sUAS or drone) flight to obtain current site features, baseline condition of the site, and to identify stressed vegetation. GES contracted a Professional Licensed Surveyor to survey ground control points to utilize for the aerial mapping and stake initial starting points for the surface-soil sampling grid.  

During the initial surface-soil investigation activities, GES utilized Clor-N-Soil kits to complete field screening for PCBs. The use of these kits allowed for real-time field analysis to determine the most impacted locations, which dictated the soil samples submitted for laboratory analysis. In addition to screening/sampling for PCBs, GES also collected discrete soil samples from six-inch intervals within the first two feet of soil for semi-volatile organic compound (SVOC) analysis and homogenized composite samples for total metals. During the surface-soil investigation, 275 locations were screened/sampled for laboratory analysis, not including all quality assurance and duplicate samples.  

GES evaluated the surface-soil analytical data and prepared tables for comparison of the results against the selected PA Act 2 Standards for the site. Additionally, several figures were generated to visually represent the spatial distribution of the PCB, metals, and SVOC impacts and PA Act 2 exceedances across the site.  

GES and PADEP will be holding a meeting with the City of Nanticoke, PA, state government officials to discuss the path forward for the project site. Based on the initial surface-soil investigation results, the remediation of the site will be extensive and require significant capital expenditure for hazardous soil disposal. 

Client Benefits

During the preparation of the work plan, GES completed a cost analysis of utilizing hand tools and field personnel to conduct the surface-soil investigation versus mobilization of a subcontractor for installation of the soil borings via direct-push technologies. It was determined that GES’ labor, materials, and equipment costs would constitute a savings to the PADEP. 

GES utilized Clor-N-Soil PCB screening kits to complete field screening and reduce the volume of samples submitted for laboratory analysis. GES completed a cost analysis and determined that the costs for laboratory analysis far exceeded the purchase of the screening kits. Additionally, GES completed field screening at six-inch intervals in each boring to determine the most likely location of SVOC impacts, thus submitting one sample from each boring versus multiple samples.  

Via thorough and well-planned systematic surface-soil investigation efforts, GES developed an initial conceptual site model that aided the PADEP in assessing the magnitude and extent of the soil impacts at the site. The pre-planned, staged approach to the investigation helped to keep costs in check and allow time to discuss the next phase of the investigation.