Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Migration of plutonium in ground water at the Nevada Test Site


Mobile colloids—suspended particles in the submicrometre size range—are known to occur naturally in ground water1, 2 and have the potential to enhance transport of non-soluble contaminants through sorption3. The possible implications of this transport mechanism are of particular concern in the context of radionuclide transport. Significant quantities of the element plutonium have been introduced into the environment as a result of nuclear weapons testing and production, and nuclear power-plant accidents. Moreover, many countries anticipate storing nuclear waste underground. It has been argued that plutonium introduced into the subsurface environment is relatively immobile owing to its low solubility in ground water4 and strong sorption onto rocks5. Nonetheless, colloid-facilitated transport of radionuclides has been implicated in field observations6, 7, but unequivocal evidence of subsurface transport is lacking3, 8, 9. Moreover, colloid filtration models predict transport over a limited distance resulting in a discrepancy between observed and modelled behaviour3. Here we report that the radionuclides observed in groundwater samples from aquifers at the Nevada Test Site, where hundreds of underground nuclear tests were conducted, are associated with the colloidal fraction of the ground water. The 240 Pu/239 Pu isotope ratio of the samples establishes that an underground nuclear test 1.3 km north of the sample site is the origin of the plutonium. We argue that colloidal groundwater migration must have played an important role in transporting the plutonium. Models that either predict limited transport or do not allow for colloid-facilitated transport may thus significantly underestimate the extent of radionuclide migration.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Location and geology of the study area.
Figure 2: Comparison of radioactivity detected in unfiltered groundwater samples from ER-20-5 well cluster.
Figure 3: Radioactivity of the colloidal minerals and comparison of Pu isotope ratios from ER-20-5 ground waters to other nuclear tests.
Figure 4: High-resolution SEM images of the colloids in ER-20-5 no.1.

Similar content being viewed by others


  1. Degueldre, C. et al. Colloids in water from a subsurface fracture in granitic rock, Grimsel test site, Switzerland. Geochim. Cosmochim. Acta 53, 603–610 (1989).

    Article  ADS  CAS  Google Scholar 

  2. McDowell-Boyer, L. M. Chemical mobilization of micron sized particles in saturated porous media under steady flow conditions. Environ. Sci. Technol. 26, 586–593 (1992).

    Article  ADS  CAS  Google Scholar 

  3. Ryan, J. N. & Elimelech, M. Colloid mobilization and transport in groundwater. Colloids Surfaces A: Physicochem. Eng. Aspects 107, 1–56 ( 1996).

    Article  CAS  Google Scholar 

  4. Nitsche, H. et al. Measured Solubilities and Speciations of Neptunium, Plutonium, and Americium in a Typical Groundwater (J-13) from the Yucca Mountain Region Milestone Report 3010-WBS (Rep. LA-12562-MS, Los Alamos National Laboratory, (1993).

    Book  Google Scholar 

  5. Triay, I. R. et al. Radionuclide Sorption in Yucca Mountain Tuffs with J-13 Well Water: Neptunium, Uranium, and Plutonium (Rep. LA-12956-MS, Los Alamos National Laboratory, (1996).

    Google Scholar 

  6. Buddemeier, R. W. & Hunt, J. R. Transport of colloidal contaminants in groundwater: radionuclide migration at the Nevada Test Site. Appl. Geochem. 3, 535– 548 (1988).

    Article  CAS  Google Scholar 

  7. Penrose, W. R., Polzer, W. L., Essington, E. H., Nelson, D. M. & Orlandini, K. A. Mobility of plutonium and americium through a shallow aquifer in a semiarid region. Environ. Sci. Technol. 24, 228–234 ( 1990).

    Article  ADS  CAS  Google Scholar 

  8. McCarthy, J. F. & Degueldre, C. in Environmental Particless 2 (eds Buffle, J.&van Leeuwen, H. P.) 247– 315 (Lewis, Ann Arbor, (1993).

    Google Scholar 

  9. Marty, R. C., Bennett, D. & Thullen, P. Mechanism of plutonium transport in a shallow aquifer in Mortandad canyon, Los Alamos National Laboratory, New Mexico. Environ. Sci. Technol. 31, 2020–2027 (1997).

    Article  ADS  CAS  Google Scholar 

  10. United States Nuclear Tests—July 1945–September 1992 (DOE/NV-209 (Rev. 14), US Department of Energy/Nevada Field Office, (1994).

  11. Smith, D. K. Characterization of nuclear explosive melt debris. Radiochim. Acta 69, 157–167 ( 1995).

    Article  CAS  Google Scholar 

  12. Borg, I. Y., Stone, R., Levy, H. B. & Ramspott, L. D. Information Pertinent to the Migration of Radionuclides in Ground Water at the Nevada Test Site (Rep. UCRL-52078, Lawrence Livermore National Laboratory, (1976).

    Google Scholar 

  13. Blankennagel, R. K. & Weir, J. E. J. Geohydrology of the eastern part of Pahute Mesa, Nevada Test Site, Nye County, Nevada Geol. Surv. Prof. Pap. 712-B (1973).

    Google Scholar 

  14. Laczniak, R. J., Cole, J. C., Sawyer, D. A. & Trudeau, D. A. Summary of Hydrogeologic Controls on Ground-Water Flow at the Nevada Test Site, Nye County, NV (Rep. 96-4109, US Geological Survey, ( 1996).

    Book  Google Scholar 

  15. Perrin, R. E., Knobeloch, G. W., Armijo, V. M. & Efurd, D. W. Isotopic analysis of nanogram quantities of plutonium by using a SID ionization source. Int. J. Mass Spectrom. Ion Phys. 64, 17–24 (1985).

    Article  ADS  CAS  Google Scholar 

  16. Thompson, J. L. Laboratory and Field Studies Related to radionuclide Migration at the Nevada Test Site October 1, 1996–September 30, 1997 (Rep. LA-13419-PR Ed., Los Alamos National Laboratory, (1998).

    Google Scholar 

  17. Smith, D. K. et al. Hydrologic Resources Management Program and Underground Test Area Operable Unit FY 1997 Progress Report (Rep. UCRL-ID-130792 Ed., Lawrence Livermore National Laboratory, (1998).

    Book  Google Scholar 

  18. Broxton, D. E., Bish, D. L. & Warren, R. G. Distribution and chemistry of diagenetic minerals at Yucca Mountain, Nye County, Nevada. Clays Clay Miner. 35, 89–110 (1987).

    Article  ADS  CAS  Google Scholar 

  19. Bates, J. K., Bradley, J. P., Teetsov, A., Bradley, C. R. & Buchholtz ten Brink, M. Colloid formation during waste form reaction: implications for nuclear waste disposal. Science 256, 649–651 ( 1992).

    Article  ADS  CAS  Google Scholar 

  20. Viani, B. E. & Martin, S. I. Groundwater Colloid Characterization (UCRL–Lawrence Livermore National Laboratory, ( 1996).

    Google Scholar 

  21. Kingston, W. L. & Whitbeck, M. Characterization of Colloids Found in Various Groundwater Environments in Central and Southern Nevada (Rep. DOE-NV/10384-36, Desert Research Inst., Las Vegas, (1991).

    Google Scholar 

  22. Comans, R. N. J. & Hockley, D. E. Kinetics of cesium sorption on illite. Geochim. Cosmochim. Acta 56, 1157–1164 (1992).

    Article  ADS  CAS  Google Scholar 

  23. Torstenfelt, B., Rundberg, R. S. & Mitchell, A. J. Actinide sorption on granites and minerals as a function of pH and colloids/pseudocolloids. Radiochim. Acta 44/45, 111–117 (1988).

    Article  Google Scholar 

  24. Triay, I. R., Lu, N., Cotter, C. R. & Kitten, H. D. Iron Oxide Colloid Facilitated Plutonium Transport in Goundwater (Am. Chemical Soc., Las Vegas, (1997).

    Google Scholar 

  25. Silva, R. J. & Nitsche, H. Actinide environmental chemistry. Radiochim. Acta 70/71, 377– 396 (1995).

    Article  CAS  Google Scholar 

  26. Stout, R. B. & Leider, H. Preliminary Waste Form Characteristics Report Version 1.0 (Rep. UCRL-ID-108314 Rev. 1, Lawrence Livermore National Laboratory, (1994).

    Google Scholar 

  27. Guillaumont, R. & Adloff, J. P. Behavior of environmental plutonium at very low concentrations. Radiochim. Acta 58/59, 53–60 ( 1992).

    Article  Google Scholar 

  28. Levy, H. B. On Evaluating the Hazards of Groundwater Contamination by Radioactivity from an Underground Nuclear Explosion (Rep. UCRL-51278, Lawrence Livermore National Laboratory, (1972).

    Google Scholar 

  29. Nimz, G. J. & Thompson, J. L. Underground Radionuclide Migration at the Nevada Test Site (Rep. DOE/NV-346, US Department of Energy, Nevada Field Office, (1992).

    Book  Google Scholar 

  30. Smith, D. K., Nagle, R. J. & Kenneally, J. M. Transport of gaseous fission products adjacent to an underground nucelar test cavity. Radiochim. Acta 73, 177–183 (1996).

    CAS  Google Scholar 

  31. Hudson, B. C., Jones, E. M., Keller, C. E. & Smith, C. W. Cavity Radius Uncertainties (Rep. LA-9211-C, Los Alamos National Laboratory, Monterey, (1981).

    Google Scholar 

Download references


We thank B. A. Martinez, F. R. Roensch, J. W. Chamberlin and G. P. Russ for help with sample analysis, and I. R. Triay, B. E. Viani, R. W. Lougheed, H. F. Shaw, F. J. Ryerson, J. F. Wild and G.B. Hudson for discussions. This work was funded partly by the Underground Test Area Project sponsored by US Department of Energy, Nevada Operations Office. Work was performed under the auspices of the US Department of Energy by Los Alamos National Laboratory and Lawrence Livermore National Laboratory.

Author information

Authors and Affiliations


Corresponding author

Correspondence to A. B. Kersting.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Kersting, A., Efurd, D., Finnegan, D. et al. Migration of plutonium in ground water at the Nevada Test Site. Nature 397, 56–59 (1999).

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing