Summary You will serve as a HYDROLOGIST within the Geology, Energy & Minerals Science Center located in Reston, VA, leading or participating on subsurface hydrologic studies of considerable scope and complexity or serving as a project leader or member of an interdisciplinary team. Duties At the full performance level (GS-13) the major duties of this position include, but are not limited to the following: Conduct fundamental and applied research in subsurface hydrology, multiphase flow through porous media, poromechanics, and related geoscience disciplines. Design, develop, and execute numerical simulations of single- and multiphase fluid flow in geologic formations, including evaluation of physical and thermodynamic impacts associated with fluid injection. Translate data from real-world geologic systems into conceptual and computational models, applying sound scientific judgment while accounting for inherent uncertainties. Collaborate effectively within multidisciplinary teams to provide technical expertise, communicate scientific results, and prepare comprehensive written reports supported by tables, figures, and charts. Present complex findings on geologic energy resources to scientific audiences at national and international conferences. Apply artificial intelligence and machine learning methods to enhance numerical modeling and simulation workflows, integrating advanced computational tools into research activities. Duties will be developmental in nature when filled below the full performance level. You may be required to travel overnight away from home up to 1-2 nights per month. You must obtain a government charge card for travel purposes. Salary: GS-12: $102,415 (step 1) - $133,142 (step 10) GS-13: $121,785 (step 1) - $158,322 (step 10) First time hires to the Federal government normally start at the step 1 rate. Qualifications All qualifications must be met by the closing date of this announcement-11/06/2026-unless otherwise stated in this vacancy announcement. To receive credit for experience, your resume MUST state either "full-time" (or "40 hours a week") or "part-time" with the number of hours worked per week to ensure proper crediting of specialized experience. Failure to adequately provide information needed to determine number of hours worked in each position may result in that time not being credited when evaluating qualifying experience. For periods of time that reflect military service, the DD-214 or Statement of Service is sufficient to meet the full and/or part-time hours requirement as the service dates will be reflected. Minimum Qualification Requirements: To qualify for this position, you must meet the following minimum qualifications: Basic Educational Requirement AND/OR Specialized Experience for the series to which you are applying. Basic Educational Requirements: In addition to the specialized experience requirements for this position, you must meet at least one of the following: A. Degree: physical or natural science, or engineering that included at least 30 semester hours in any combination of courses in hydrology, the physical sciences, geophysics, chemistry, engineering science, soils, mathematics, aquatic biology, atmospheric science, meteorology, geology, oceanography, or the management or conservation of water resources. The course work must have included at least 6 semester hours in calculus (including both differential and integral calculus), and at least 6 semester hours in physics. Calculus and physics, as described above, are requirements for all grade levels. You must submit transcripts. -OR- B. Combination of education and experience: course work as shown in A above, plus appropriate experience or additional education. -AND- To qualify for this position at the GS-12 grade level: Specialized Experience Requirement: you must possess at least one full year of specialized experience equivalent to the GS-11 level in the Federal service (obtained in either the public or private sectors). Specialized experience must include fundamental or applied research in subsurface hydrology or multiphase flow through porous media. Experience could include assisting in selecting, constructing, calibrating, and validating numerical groundwater models; integrating field observations, geologic data, and hydrologic measurements; and simulating groundwater flow, aquifer responses, and groundwater-surface water interactions under varying hydrologic and management conditions. At this level, experience should demonstrate a very good knowledge of the principles of hydrology and their application, and the ability to independently perform scientific work of considerable difficulty. You must include hours per week worked. -OR- To qualify for this position at the GS-13 grade level: Specialized Experience Requirement: you must possess at least one full year of specialized experience equivalent to the GS-12 level in the Federal service (obtained in either the public or private sectors). Specialized experience must include leading a team in fundamental or applied projects of subsurface hydrology or multiphase flow through porous media. Experience could include selecting, constructing, calibrating, and validating numerical groundwater models; integrating field observations, geologic data, and hydrologic measurements; and simulating groundwater flow, aquifer responses, and groundwater-surface water interactions under varying hydrologic and management conditions. The complexity of this work typically required extensive modification and adaptation of standard procedures, methods, and techniques, and the development of totally new methods and techniques to address novel or obscure problems for which guidelines or precedents were not substantially applicable. At this level, experience should demonstrate extensive knowledge of the principles of hydrology and highly developed ability in their application, and wide latitude for the exercise of independent judgment to perform scientific work of marked difficulty and responsibility. You must include hours per week worked. Volunteer Experience: Experience refers to paid and unpaid experience, including volunteer work done through National Service programs (e.g., Peace Corps, AmeriCorps) and other organizations (e.g., professional; philanthropic; religious; spiritual; community, student, social). Volunteer work helps build critical competencies, knowledge, and skills and can provide valuable training and experience that translates directly to paid employment. You will receive credit for all qualifying experience, including volunteer experience. Education This position does not allow substituting education for experience. This position has a mandatory education requirement. You must submit a copy of your transcript(s) to support claimed education if substituting education for experience. Transcripts must include your name, school name, grades, credit hours earned, major(s), grade point average or class ranking, and date the degree was conferred, if applicable. A typed list of courses, grades, semester/quarter hours, GPA, etc. will not be accepted. Non-submission may result in being rated not qualified for the position. Unofficial transcripts are acceptable, but if you are selected for this position and you used your education to qualify, you must provide official transcripts before you begin work. Foreign Education: To receive credit for education completed outside the United States, you must show proof that the education has been submitted to a private organization that specializes in interpretation of foreign educational credentials and such education has been deemed at least equivalent to that gained in conventional U.S. education programs. Recognition of Foreign Qualifications | U.S. Department of Education. https://www.ed.gov/about/initiatives/international-affairs/recognition-of-foreign-qualification