Formatted Title
Application of Sustainable Remediation at a Pharmaceutical Industrial Site Based on High Resolution Site Characterization
Background/Objectives
Diesel oil leakage is one of the most common source of contaminants in industrial sites in Brazil; however, due to soil heterogeneity and weathering conditions, delineation of light non aqueous phase liquid (LNAPL) can be a challenge when applying conventional investigation approaches. In this context, the application of high-resolution site characterization approaches provides dense data acquisition for a real time understanding of impact, demonstrating to be a highly time and cost-effective option. The following approach provided information for LNAPL conceptual site model (CSM) update in a short time frame (10 days) and detailed perspective of the impact distribution based on a mass flux approach (Stratigraphic Flux™), which allowed to surgically target the mass that matter most through the remedial approach selected.
Approach/Activities
The investigation strategy was based on the application of a laser induced fluorescence tool (Ultra Violet Optical Screening Tool [UVOST]) to efficiently delineate LNAPL impacts, which had been detected through fluorescence response (RE%) of their polycyclic aromatic hydrocarbon (PAH) constituents. A Hydraulic Profiling Tool was later applied to refine the mapping of mass transport and storage zones of the aquifer. The combination of data from these two methods was used to select soil (whole core soil sampling) and groundwater (vertical aquifer profile at transport zones) sampling horizons throughout the entire profile and to obtain quantitative data on the distribution of contaminant mass. Finally, CSM was updated using the Stratigraphic Flux™ approach which provided a graphical flux-based CSM that uses a heat map to graphically show where most of the contaminant migration occurs (relative mass flux) – the heat map is obtained combining hydraulic conductivity data (in this case, HPT Est. K) and samples chemical concentration.
Results/Lessons Learned
As a result, Arcadis was able to determine that 76% of the total TPH mass flux was at the hotspot cross section, and define the best remedial strategies, and also considered Arcadis-Sustainability-Strategy by applying the following techniques: Thermal In Situ Sustainable Remediation (TISR™), Dual Phase Extraction (DPE), Dynamic Groundwater Recirculation (DGR™), and BioSparging. Additionally, targeting to reduce waste generation in the treatment process (contaminated granular activated carbon), the project installed a catalytic oxidizer (CatOx) as an alternative of treatment method. TISR™ is a solar power-based low temperature thermal remediation technique, which enhances contaminant physical, biological, and chemical attenuation processes without injecting any water/product in the Aquifer. Based on Arcadis Brazil previous project experiences with TISR™ in association with other technologies, it allows reduction up to 50% of projects’ life cycle costs. It is expected that the full-scale remediation is going to be concluded by the end of Q1/2024 and, additionally, the project’s footprint has been evaluated through Arcadis’ Green Metric Analytics™ tool, an innovative solution, which calculates the carbon emission equivalent generated in each phase of a project, including the lifecycle of the materials used.