Subsurface Reactive Fate & Transport Modeling Scientist

Savannah River National Laboratory (SRNL) is seeking a midcareer scientist with strong expertise in subsurface reactive fate and transport modeling to support research and mission-driven applications focused on environmental remediation, groundwater protection, and long-term stewardship at the Savannah River Site (SRS) and other DOE-managed lands.

The successful candidate will develop, apply, and communicate advanced numerical models to predict the coupled hydrologic, geochemical, and biological processes governing contaminant behavior in complex subsurface environments. This role supports SRNL’s mission to deliver credible science-based solutions that ensure the protection of human health and the environment.

The position involves technical leadership, collaboration across multidisciplinary teams, mentoring of early-career staff, and direct interaction with DOE customers and regulatory stakeholders.

Technical Modeling & Analysis

• Develop and apply reactive transport models (e.g., PFLOTRAN, TOUGHREACT, CrunchFlow/CrunchTope, PHREEQC, HYDRUS, COMSOL, FEFLOW) to evaluate contaminant fate, plume evolution, and remedial strategy performance.
• Integrate aqueous geochemistry, sorption/kinetics, mineral reactions, and redox transformations into model frameworks.
• Conduct model calibration, validation, sensitivity analysis, and uncertainty quantification using tools such as PEST/PEST++, DAKOTA, or Bayesian methods.
• Develop and refine conceptual site models using hydrogeologic, geochemical, mineralogical, and field performance data.

Data Integration & Interpretation

• Assimilate field monitoring, laboratory testing, geospatial data, and historical site knowledge into modeling workflows.
• Generate reduced-order models, computational surrogates, or decision-support tools to inform risk assessments and remediation planning.
• Produce high-quality visualizations, technical interpretations, and defensible documentation suitable for DOE and regulatory review.

Program and Project Support

• Serve as a technical lead or task manager for modeling efforts within multi-institutional or multi-disciplinary projects.
• Contribute to proposal development, R&D planning, and engagement with DOE program managers, site operations personnel, and regulators.
• Ensure all deliverables meet SRNL’s standards for quality, safety, and regulatory compliance.

Collaboration & Mentorship

• Mentor junior scientists, modelers, and interns on modeling techniques, scientific writing, and workflow reproducibility.
• Work closely with SRNL hydrologists, geochemists, microbial scientists, field engineers, and data scientists to design studies and integrate models with experimental work.

Competencies

• Strong technical judgment and ability to design rigorous, defensible modeling studies.
• Effective communicator, able to translate complex technical outputs into clear, actionable insights.
• Demonstrated ability to work effectively in multidisciplinary teams and build strong collaborations across SRNL, SRS operations, and partner organizations.
• Commitment to safety, quality, and scientific integrity.

Minimum Qualifications:

• Ph.D. in Hydrogeology, Geosciences, Environmental Engineering, Chemical Engineering, Civil Engineering, or related field with 6-8+ years of relevant experience; or M.S. with 8-10 years of relevant experience.
• Ability to obtain and maintain security clearance; U.S. citizenship is legally required.
• Demonstrated experience developing and calibrating reactive fate and transport models for groundwater or vadose-zone systems.
• Strong foundation in aqueous geochemistry and subsurface flow and transport processes.
• Proficiency in Python (preferred), MATLAB, or R for model pre- and post-processing.

• Experience preparing technical reports and communicating results to technical and non-technical audiences.

Preferred Qualifications:

• Experience with HPC environments, parallel computing, containers, or cloud-ready workflows.
• Background in geostatistics, stochastic modeling, or Bayesian methods.
• Experience with contaminants relevant to DOE legacy sites (e.g., uranium, technetium, strontium, cesium, nitrate, chlorinated solvents, PFAS).
• Familiarity with DOE Orders, CERCLA, and other environmental regulatory frameworks.
• Experience with reduced-order modeling, machine learning integration, or physics-informed ML methods.
• Experience supporting or leading DOE-funded R&D programs.

• Knowledge of GIS tools (ArcGIS/QGIS), geospatial analysis, and database management.

Work Environment & Additional Requirements

• Position is based at SRNL within the Savannah River Site; hybrid work arrangements may be considered.
• Occasional travel to project sites, conferences, or sponsor meetings (up to 10-15%).

“We put science to work!”

Savannah River National Laboratory (SRNL) is a multi-program laboratory applying state of the art science and practical, high-value, cost-effective solutions to complex technical problems to protect the nation. Located at the U.S. Department of Energy’s (DOE) Savannah River Site (SRS) in Aiken SC, the laboratory develops and deploys innovative technologies to address some of the nation’s environmental, energy, and national security challenges.

Battelle Savannah River Alliance (BSRA) is constantly assessing trends to provide the best possible benefits to our workforce. We also negotiate cost effective premiums that will meet the needs of our evolving workforce.

Some of the *Benefits offered to employees include:

*Benefits vary based upon employment status

• Highly competitive Medical, Dental, and Vision options including HSA options with company provided seed
• Short- & Long-Term Disability (company paid)
• Life Insurance Non-Contributary 1X salary (company paid)
• AD&D Non-contributary 1x salary (company paid)
• Savings & Investment plan:
• • Qualified Non-Elective Company Contribution of 5% each pay period with immediate vesting
  • Company match 50 cents/dollar up to 8% (5 yrs. vesting in company match)
• Contributory Life Insurance up to 5x Salary with $1M Cap
• Contributory AD&D (employee, spouse and children)
• Paid Time Off
• Employee Assistance Plan
• SRNL offers a competitive relocation package to ease the transition process. Domestic and international relocation assistance is available for certain positions.

For more information about our benefits, working here, and living here, visit the “About” tab at www.srnl.doe.gov.

BSRA is an Equal Opportunity/Affirmative Action employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, disability, or protected veteran status. BSRA is also committed to making our workplace accessible to individuals with disabilities and will provide reasonable accommodations, upon request, for individuals to participate in the Application and hiring process. Please email us at SRNLRecruiting@srnl.doe.gov with any questions regarding the hiring process or to request an accommodation.