Groundwater Modeler

Navarro Research and Engineering is recruiting a Groundwater Modeler (3953) in Las Vegas, NV.

Navarro Research & Engineering is an award-winning federal contractor dedicated to partnering with clients to advance clean energy and deliver effective solutions for complex challenges in the nuclear and environmental fields. Joining Navarro means being a part of an exceptional team committed to quality and safety while also looking for innovative strategies to create value for the client's success. Headquartered in Oak Ridge, Tennessee, Navarro has active programs in place across the nation for DOE/NNSA, NASA, and the Department of Defense.

Navarro is seeking a Groundwater Modeler with Earth Vision experience to support groundwater modeling activities for the Nevada National Security Site (NNSS). This full-time, long-term position will be based in Navarro's Las Vegas, Nevada office and will support technical modeling, data evaluation, and visualization efforts associated with groundwater systems at NNSS.

The Groundwater Modeler will develop and apply MODFLOW-based groundwater models, integrate hydrogeologic and geologic datasets, and support technical analyses used to evaluate groundwater flow conditions, radionuclide contaminant transport, model performance, and site-specific environmental decision-making. The role requires strong technical judgment, attention to quality, and the ability to communicate modeling assumptions, methods, and results clearly to technical and project stakeholders.

• Develop, maintain, calibrate, and document groundwater flow and contaminant transport models for NNSS using the MODFLOW suite of tools.
• Use Earth Vision to develop, visualize, and interpret geologic and hydrogeologic data, including strati graphic surfaces, model layers, and conceptual site model elements.
• Compile, review, and evaluate groundwater, geologic, hydrologic, hydraulic, contaminant concentration, and site characterization data to support model development, calibration, and refinement.
• Prepare model input files, boundary conditions, hydraulic parameters, stress packages, calibration targets, model outputs, and supporting technical documentation.
• Evaluate model results, perform sensitivity checks, assess uncertainty, and support interpretation of groundwater flow conditions and site-specific hydrogeologic behavior.
• Generate maps, figures, cross sections, tables, model visualizations, and technical summaries to support project deliverables and client communications.
• Coordinate with hydro geologists, geologists, engineers, environmental scientists, project managers, and client representatives to align modeling activities with project objectives, schedules, and quality requirements.
• Apply appropriate quality assurance, configuration control, data management, and technical review practices for modeling files, datasets, calculations, and deliverables.
• Support technical reports, presentations, work planning, and project meetings related to groundwater modeling and environmental support activities at NNSS.

• Bachelor's degree in hydrogeology, geology, hydrology, geoscience, environmental science, civil engineering, environmental engineering, or a closely related technical discipline.
• Demonstrated experience developing or supporting groundwater models using MODFLOW.
• Demonstrated experience with model optimization tools (such as PEST) and Monte Carlo (or equivalent) uncertainty approaches.
• Demonstrated experience using Earth Vision for geologic or hydrogeologic model development, visualization, and interpretation.
• Working knowledge of groundwater flow principles, stratigraphy, hydrogeologic conceptual site models, model calibration, sensitivity evaluation, and technical documentation.
• Ability to evaluate and integrate large technical datasets, including water-level data, hydraulic properties, geologic units, pumping or recharge information, and other model-supporting data.
• Ability to prepare clear technical deliverables, communicate modeling assumptions and results, and work effectively with multidisciplinary technical teams.
• Strong attention to detail, data quality, documentation, file…