Environmental Geoscience is a scientific field that investigates the complex interactions between human activity and the Earth’s natural systems. It applies the principles of traditional Earth sciences to address environmental challenges resulting from societal development and resource use. This interdisciplinary study focuses on understanding how the planet’s physical processes respond to human-induced change, providing the foundation for informed decisions about land use, environmental protection, and sustainable development.
Defining Environmental Geoscience
This field represents the intersection of classical Earth sciences, such as geology, hydrology, and geochemistry, with environmental protection. Environmental Geoscience focuses primarily on the near-surface environments that directly affect and are affected by human society. This includes the lithosphere (solid earth), the hydrosphere (all water bodies and groundwater), and the lower portion of the atmosphere.
It views the Earth as a single, interconnected system where a change in one component causes a cascading effect across others. Geoscientists analyze the natural processes that have shaped the planet, applying that knowledge to the modern system and the impacts of human populations. The goal is to understand the physical environment well enough to anticipate the consequences of resource extraction, waste disposal, and urbanization, and to devise strategies that mitigate environmental harm.
Addressing Specific Environmental Challenges
Environmental geoscientists are often called upon to manage the widespread issue of subsurface contamination, which falls under contaminant hydrogeology and soil remediation. They characterize the geology and hydrogeology of a site to trace contaminant plumes, which are areas of groundwater or soil polluted by substances like industrial solvents or petroleum hydrocarbons. Remediation methods involve both in-situ and ex-situ techniques, such as the pump-and-treat process where contaminated groundwater is extracted, cleaned, and reinjected. More advanced in-situ techniques include injecting chemical oxidants to break down contaminants or using Permeable Reactive Barriers (PRBs), which are underground walls filled with reactive media to filter pollutants as the groundwater flows through.
The field is also deeply involved in mitigating natural hazards by assessing the risk of geological events. For instance, geoscientists analyze seismic slope stability to predict the likelihood of landslides during an earthquake. They employ methods like the Newmark sliding-block model to calculate the potential displacement of a slope mass under seismic loading. Additionally, they perform geotechnical characterization to identify areas prone to soil liquefaction, where saturated, loose soil temporarily loses strength during ground shaking. Mitigation strategies include creating hazard maps to guide land-use planning and designing effective subsurface drainage systems to increase slope stability.
Environmental geoscientists are integral to the sustainable management and protection of geological resources. This includes the responsible sourcing of construction materials like aggregates (sand, gravel, and crushed rock) required for infrastructure projects. They also play a major role in protecting vital groundwater resources by mapping and monitoring aquifers to ensure the long-term quality and quantity of water supplies. As the world transitions to new energy sources, geoscientists are essential for locating and managing the extraction of raw materials, such as lithium and cobalt, needed for battery technology.
The Geoscientist’s Professional Role
The professional duties of an environmental geoscientist center on site characterization and environmental due diligence. A common early task is conducting a Phase I Environmental Site Assessment (ESA), which is a historical and visual review of a property to identify potential liabilities known as Recognized Environmental Conditions (RECs). This initial assessment relies on reviewing historical records and regulatory documents, without collecting any physical samples.
If a potential concern is identified, the geoscientist manages the more intrusive Phase II ESA, which involves collecting physical samples of soil, groundwater, or soil vapor. They oversee the drilling of soil borings and the installation of monitoring wells, using techniques like direct push technology for sample collection. Strict adherence to quality assurance and quality control (QA/QC) procedures is maintained to ensure sample integrity from the field to the accredited laboratory.
The geoscientist’s ultimate task is consulting and reporting, translating complex scientific data into actionable recommendations for clients, engineers, and regulatory agencies. These reports document the environmental status of a site, confirm the extent of contamination, and propose remediation strategies that meet required standards. This work is often performed to comply with environmental laws and protect stakeholders from liability.