Using innovative technologies, Gradient excels at developing computer-based tools to collect, organize, analyze, and visualize large amounts of historical site data accurately and efficiently. We store that data in our in-house Information Resource Center (IRC), a centralized hub for research run by our dedicated staff of research librarians. Our IRC enables Gradient scientists to take a deeper look at historical documents, features, and data to tell a complete story of historical sites and other potentially responsible parties (PRPs) or contamination sources.
Contaminant Release and Migration Conceptual Model Development
Gradient reviewed historical environmental investigations, aerial imagery, and other records dating back to the 1940s to assist in the development of a conceptual model of contaminant release and migration in groundwater. We incorporated a comprehensive set of groundwater quality data into a database and developed maps illustrating plume signature and evolution over time. Our analysis included aerial images dating back to the 1930s and an evaluation of changes in land cover and use.
Technical Support for Allocation of Costs Associated with Regional Contaminant Plume
Using historical aerial photographs, environmental investigations, and other records dating back as far as the 1930s, Gradient identified pertinent site features and changes in land cover and use. We developed a conceptual model of contaminant release and migration in groundwater. We incorporated a comprehensive set of groundwater quality data into a database to develop 3D plume representations, using Earth Volumetric Studio (EVS) software to illustrate plume evolution over time and improve a transient numerical model.
Historical Review and Web-Based GIS Development
Gradient performed a comprehensive historical review of a former manufactured gas plant (MGP) site and its vicinity from the 1880s to the present, to guide site characterization efforts and identify other potentially responsible parties (PRPs). We obtained, analyzed, and combined historical photographs, maps, and other images, along with information and data from hydrogeologic reports and environmental investigations. We also developed a web-based GIS mapping application to help communicate the results of the analyses to stakeholders.