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    The Closing Date has been updated to March 4, 2019.

    What General Information Do I Need to Know About This Position? 

    Salary: $79,720 (Step 01) to $103,639 (Step 10); NOTE: First time hires to the Federal Government are typically hired at the Step 01.

    There is one vacancy; however, this announcement may be used to fill additional vacancies if they become available.

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    Mendenhall Research Fellowship - Research Opportunity #17-30 Biogeochemistry of the Sulfur Cycle as It Relates to Mineral Resources in the Midcontinent Region

    The Upper Midcontinent Region is a highly prospective area for future mineral resource development. Current priority exploration and development projects include copper-nickel-cobalt-platinum group element mafic deposits (Ripley, 2014), sediment-hosted copper-silver deposits (Bornhorst and Williams, 2013), and banded iron-formation deposits (Cannon and others, 2007). In all of these deposits, mineral resources are associated with sulfide minerals, either in the ores themselves or in waste rock that will be removed to access the ores. In such settings, a detailed understanding of the sulfur cycle is essential for effective mitigation of adverse environmental effects, and ultimately sustainable development. Acid-mine drainage is the result of the weathering of a sulfide mineral, such as pyrite in the presence of oxygen and water to produce sulfuric acid and iron precipitates. The resultant sulfur-rich drainage may experience a variety of fates including dilution, evaporative concentration, oxidation, or reduction. Oxidation may result in elevated dissolved sulfate concentrations. Subsequently, dissolved sulfate may undergo bacterial sulfate reduction downstream in the anoxic sediments of wetland areas. The resulting elevated dissolved sulfide concentrations have been shown to be toxic to wild rice (Fort and others, 2014), an important subsistence food source for Native Americans in the Upper Great Lakes region. In fact, the State of Minnesota recently considered adopting a more process-oriented approach to establishing appropriate environmental guidelines particularly to protect wild rice. Further, sulfate-reducing bacteria are known to be the primary methylators of mercury in aquatic ecosystems, and their activity can be enhanced by elevated dissolved sulfate concentrations. Methylmercury, a potent neurotoxin, is the mercury species that bioaccumulates in aquatic food webs and results in fish consumption advisories, which is a major concern for sport fishermen, commercial fishing, and Native Americans in the Upper Great Lakes region. Thus, the sulfur cycle, particularly as related to mining, can have far-reaching influences on many aspects of environmental health of a region.

    Proposed Duty Station: Reston, VA

    Areas of Ph.D.: Geology, geochemistry, hydrology, chemistry, ecology (candidates holding a Ph.D. in other disciplines but with knowledge and skills relevant to the Research Opportunity may be considered).

    Qualifications: Applicants must meet one of the following qualifications: Research Geologist; Research Chemist; Research Hydrologist; Research Physical Scientist; Research Ecologist.

    (This type of research is performed by those who have backgrounds for the occupations stated above. However, other titles may be applicable depending on the applicant's background, education, and research proposal. The final classification of the position will be made by the Human Resources Specialist.)


    Physical/Environmental Demands:

    The office assignments normally involve everyday risks or discomforts that require normal safety precautions typical of offices or meeting and training rooms.

    The laboratory assignments involve exposure to moderate risks and discomforts, such as those due to: irritating chemicals; noxious fumes; flammable liquids; radiation; potentially pathogenic bacteria; and/or carcinogenic materials. Some laboratory work may require special safety precautions and/or protective clothing and equipment.

    Field assignments involve outdoor work where there is considerable walking, climbing over rough or mountainous terrain, and heavy lifting of equipment. However, work during the field season involves exposure to a wide range of weather and temperature conditions, poisonous growth, insects, and potentially dangerous wildlife. Some field work may require special safety precautions and/or protective clothing and equipment.

    Travel Required

    Occasional travel - Overnight travel of up to 5 nights per month may be required.

    Supervisory status


    Promotion Potential


This job originated on www.usajobs.gov. For the full announcement and to apply, visit www.usajobs.gov/GetJob/ViewDetails/518617900. Only resumes submitted according to the instructions on the job announcement listed at www.usajobs.gov will be considered.