Environmental Earth Sciences

, Volume 72, Issue 7, pp 2607–2620 | Cite as

Using field analogue soil column experiments to quantify radon-222 gas migration and transport through soils and bedrock of Halifax, Nova Scotia, Canada

  • Kelsey E. O’Brien
  • Dave Risk
  • Daniel Rainham
  • Anne Marie O’Beirne-Ryan
Original Article


Radon gas is a human health hazard; long-term exposure to high radon concentrations through inhalation is the second leading cause of lung cancer. Nova Scotia has been previously identified as a potential high risk region because of the geology. As such, the gas transport through Halifax’s fine grained leucomonzogranite (FGL) unit of the South Mountain Batholith needed to be quantified to further remediation efforts. Using controlled laboratory experiments, four different soil columns were created using the Halifax Regional Municipality’s (HRM) highest producing field tills and bedrock. Permeability, diffusivity, radon-222 gas concentrations, and gas transit time/speed were measured in both dry tills (field moisture) and wet tills (simulated rain event moisture). Columns with HRM till displayed the highest radon concentrations, and were less permeable with additional moisture. Radon diffusivity calculated from CO2 was 7.52 × 10−8 m2 (dry), and 3.37 × 10−8 m2 (wet); diffusivity calculated from 222Rn was 7.30 × 10−7 m2 (dry), and 6.47 × 10−7 m2 (wet). The average FGL transit time in a 60 cm column was 3.57 days (dry), and 3.82 days (wet). Locally this study presents two different methods for diffusivity calculations, for a unit lacking previous diffusivity information. The radon gas concentrations and transport speeds quantified the transport mechanisms within the till. Globally, the correlation between soil moisture, and radon/permeability values was established using these results. The link between diffusivity and permeability was also confirmed using field tills. Implications were made for building foundations, as well as the depth and type of material necessary to reduce radon gas from reaching the surface.


Radon Soil gas Health risk Gas transport Diffusivity Permeability 



The authors are extremely grateful to the following people and organizations: Ken Ford, Peter Friske, and Rick McNeil (Geological Survey of Canda) for the generous use of the soil sampling equipment, and the Radon JOK Portable Permeability Machine. George O’Reilly (Nova Scotia Department of Natural Resources) for uranium expertise and assistance collecting bedrock samples. John Gosse (Dalhousie University) for expertise and assistance collecting soil samples. Nick Nickerson (St. Francis Xavier) for invaluable modeling help and guidance. Terry Goodwin (Imperial Soil Limited) for radon expertise and reviews. Paul Hill (Dalhousie University) for assistance and use of soil sieving facilities. And two anonymous reviewers for their helpful edits. Funding from: the Lung Association of Nova Scotia, Environmental Systems Research Institute (ESRI), Dalhousie University, and St. Francis Xavier University.


  1. Appleton JD, Miles JCH, Young M (2011) Comparison of Northern Ireland radon maps based on indoor radon measurements and geology with maps derived by predictive modelling of airborne radiometric and ground permeability data. Sci Total Environ 409:1572–1583CrossRefGoogle Scholar
  2. Ball B, Scott A, Parker J (1999) Field N2O, CO2 and CH4 fluxes in relation to tillage, compaction and soil quality in Scotland. Soil Tillage Res 53:29CrossRefGoogle Scholar
  3. Chao CYH, Tung TCW, Burnett J (1997) Influence of ventilation on indoor radon level. Build Environ 32.6:527–534CrossRefGoogle Scholar
  4. Chen J (2009) A preliminary design of a radon potential map for Canada: a multi-tier approach. Environ Earth Sci 58:775–782 doi: 10.1007/s12665-009-0073-x CrossRefGoogle Scholar
  5. Chen J et al (2008) A Preliminary radon map for Canada according to health region. Radiat Prot Dosim 130:92–94CrossRefGoogle Scholar
  6. Chen J et al (2009) Correlation of soil radon and permeability with indoor radon potential in Ottawa. Radiat Prot Dosim 136:56–60CrossRefGoogle Scholar
  7. Dubois G (2005) An overview of radon surveys in Europe. European Commission, pp. 1–168Google Scholar
  8. Dyck W et al (1976) Well water trace element reconnaissance, Eastern Maritime Canada. J Geochem Explor 6:139–162CrossRefGoogle Scholar
  9. EPA (1993) Protocols for radon and radon decay product measurements in homes. Environmental Protection Agency Office of Air and Radiation 6604J.402-R-93-003Google Scholar
  10. Espinosa G, Gammage RB (2003) A representative survey of indoor radon in the sixteen regions in Mexico City. Radiat Prot Dosim 103:73–76CrossRefGoogle Scholar
  11. Fisher BE (2006) Regional till and rock geochemical surveys of the South Mountain Batholith by the Nova Scotia Department of Natural Resources over western Nova Scotia. DP ME 137, Version 2Google Scholar
  12. Freeze RA, Cherry JA (1979) Groundwater. Prentice-Hall, Inc, New Jersey, p 604Google Scholar
  13. Friske PWB et al (2010) North American soil geochemical landscapes project: Canadian field protocols for collecting mineral soils and measuring soil gas radon and natural radioactivity. Geol Surv of Can Open File 6282:177Google Scholar
  14. Goodwin TA et al (2008) Radon soil gas in the Halifax Regional Municipality: should we be concerned? Nova Scotia Department of Natural Resources, Mineral Resources Branch, Report of Activities ME 2009-1:35–44Google Scholar
  15. Goodwin TA et al (2009) Radon soil gas in Nova Scotia. In: MacDonald DR, Mills KA (eds) Mineral Resources Branch, Report of Activities 2008, Nova Scotia Department of Natural Resources ME 2009-1:25–34Google Scholar
  16. Goodwin TA et al (2010) Radon soil gas in the Halifax Regional Municipality: progress report on the 2009 Sampling Program. Mineral Resources Branch, Report of Activities 2010, Nova Scotia Department of Natural Resources ME 2010-1:29–34Google Scholar
  17. Grantham DA (1986) The occurrence and significance of uranium, radium and radon in the water supplies in Nova Scotia. Nova Scotia Department of Health ME 1986–1970Google Scholar
  18. Groves-Kirkby CJ et al (2006) Time-integrating radon gas measurements in domestic premises: comparison of short-, medium- and long-term exposures. J Environ Radioact 86:92–109CrossRefGoogle Scholar
  19. Guastaldi EG et al (2013) A multivariate spatial interpolation of airborne gamma ray data using the geological constraints. Remote Sens Environ 137:1–11CrossRefGoogle Scholar
  20. HC (2012) Radon. Radiation Protection Bureau, Healthy Environments and Consumer Safety Branch, Health Canada H13-7/119-2012E-PDFGoogle Scholar
  21. Hillel D (1998) Environmental soil physics. Academic Press, San Diego, p 771Google Scholar
  22. Hillel D (2004) Introduction to environmental soil physics. Elsevier Science, CaliforniaGoogle Scholar
  23. Holkko J, Liukkonen S (1992) Radon diffusion in Finnish glacial till soil. Radiat Prot Dosim 45.1:231–233Google Scholar
  24. Jackson SA (1990) A survey to measure domestic concentrations of radon gas in Nova Scotia. Nova Scotia Department of the Environment, unpublished reportGoogle Scholar
  25. Je I (1998a) Bedrock structure control on soil-gas radon-222 anomalies in the Toronto Area. Environ Eng Geosci 4:445–454Google Scholar
  26. Je I (1998b) Soil-gas radon-222 anomalies in the south central Ontario, Canada. From: M.Sc. Thesis, University of TorontoGoogle Scholar
  27. Jiranke M, Neznal M, Neznal M (1999) Sub-slab depressurization systems: effectiveness and soil permeability. Radon Living Environ 23:19–23Google Scholar
  28. Keen BA (1931) The physical properties of soil. Longman Greenand Company, New York, p 380Google Scholar
  29. Kemski J et al (2006) Radon risk prediction in Germany based on gridded geological maps and soil measurements. In: Radon investigations in Czech Republic XI and the 8th international workshop on the geological aspects of radon risk mapping, pp 139–156Google Scholar
  30. Kemski J, Klingel R, Siehl A (2007) From radon hazard to risk prediction-based on geologic maps, soil gas and indoor measurements in Germany. Environ Geol 56:1269–1279CrossRefGoogle Scholar
  31. Keppie JD (2006) Geological map of the Province of Nova Scotia, scale 1:500,000. Digital Version of Nova Scotia Department of Natural Resources Map ME 2000-1 DP ME 043, Version 2Google Scholar
  32. Letourneau EG et al (1992) Levels of radon gas in Winnipeg homes. Radiat Prot Dosim 45:531–534Google Scholar
  33. Lewis CFM et al (1998) Earth science and engineering: urban development in the metropolitan Halifax region. In: Karrow PF, White OL (eds) Urban geology of Canadian Cities. Geologic Assoc Can Special Paper 42:409–444Google Scholar
  34. MacDonald M, Horne R (1987) Geological map of Halifax and Sambro (NTS sheets 11 D/12 and 11 D/05), Nova Scotia. Nova Scotia Depart of Mines and Energy, scale 1:50,000 Map 87-6Google Scholar
  35. Menetrez MY, Mosley RB (1996) Evaluation of radon emanation from soil with varying moisture content in a soil chamber. Environ Int 22.1:S447–S453CrossRefGoogle Scholar
  36. Nazaroff WW(1992) Radon transport from soil to air. Rev Geophys 30:137–160CrossRefGoogle Scholar
  37. Neznal M et al (2004) The new method for assessing the radon risk of building sites. Czech Geol Surv 16:1–48Google Scholar
  38. NSDPE (2009) Education department radon testing 2008: Nova Scotia Department of Education.
  39. O’Beirne-Ryan AM, Zentilli M (2006) Weathering of Devonian monzogranites as recorded in the geochemistry of saprolites from the South Mountain Batholith, Nova Scotia, Canada. Atlan Geol 42:151–157Google Scholar
  40. O’Brien KE (2010) Radon soil gas within the Halifax Regional Municipality, Nova ScotiaGoogle Scholar
  41. O’Brien KE, Goodwin TA, Risk D (2011) Radon soil gas in the Halifax Regional Municipality, Nova Scotia, Canada. Atlan Geol 47:112–124Google Scholar
  42. O’Reilly GA, Goodwin TA, Fisher BE (2009) A GIS-based approach to producing a map showing the potential for radon in indoor air in Nova Scotia. Nova Scotia Department of Natural Resources, Mineral Resources Branch, Report of Activities ME 2010-1:95–97Google Scholar
  43. Penman RI (1940) Gas and vapour movement in soil: the diffusion of vapours through porous solids. J Agric Sci 30:437–462CrossRefGoogle Scholar
  44. Risk D, Kellman L, Beltrami H (2008) A new method for in situ gas diffusivity measurement and applications in the monitoring of subsurface CO2 production. J Geophys Res 113:1–9Google Scholar
  45. Russell MB (1952) Soil aeration and plant growth. Soil physical conditions and plant growth. Academic, New YorkGoogle Scholar
  46. Ryan RJ, O’Beirne-Ryan AM (2007) Preliminary Report on the origin of uranium occurrences in the Horton Group of the Windsor Area, Nova Scotia. Nova Scotia Department of Natural Resources, Mineral Resources Branch, Report of Activities ME-2007-1:137–157Google Scholar
  47. Ryan RJ, O’Beirne-Ryan AM (2009) Uranium occurrences in the Horton Group of the Windsor Area, Nova Scotia and the environmental implications for the Maritimes Basin. Atlan Geol 45:171–190CrossRefGoogle Scholar
  48. Ryan RJ et al (2009) Mobility of uranium and radon associated with uranium roll front occurrences in the Horton Group of the Windsor Area, Nova Scotia, Canada. Nova Scotia Department of Natural Resources, Mineral Resources Branch, Report of Activities ME 2010- 1:162–165Google Scholar
  49. Selinus O et al (2005) Essentials of medical geology: impacts of the natural environment on public health. Elsevier Avademic PressGoogle Scholar
  50. Shi X et al (2006) Spatial association between residential radon concentration and bedrock types in New Hampshire. Environ Geol 51:65–71CrossRefGoogle Scholar
  51. Silker WB et al (2007) Measurement of radon diffusion and exhalation from uranium mill tailings piles. Environ Sci Technol 13.8:962–964CrossRefGoogle Scholar
  52. Solcova O, Snajdaufova H, Schneider P (2001) Multicomponent counter-current gas diffusion in porous solids: the Graham’s-law diffusion cell. Chem Eng Sci 56:5231–5237CrossRefGoogle Scholar
  53. Stea RR, Fowler JH (1979) Pleistocene geology of the eastern shore region Nova Scotia (sheet 3). Nova Scotia Department of Mines and Energy, Scale 1:100,000 Map 79-3Google Scholar
  54. Stea RR, Fowler JH (1981) Pleistocene geology and till geochemistry of central Nova Scotia (sheet 4). Nova Scotia Department of Mines and Energy, Scale 1:100,000 Map 81-1Google Scholar
  55. USEPA (1993) EPA’s Map of Radon Zones, National Summary. United States Environmental Protection Agency Air and RadiationGoogle Scholar
  56. Utting DJ (2009) LiDAR-based glacial geology of the Halifax metropolitan area. In: MacDonald DR, Mills KA (eds) Mineral Resources Branch, report of activities 2008, ME 2009-1:129–137Google Scholar
  57. Washington J et al (1994) Gaseous diffusion and permeability in four soil profiles in central Pennsylvania. Soil Sci 157:65–76. doi: 10.1097/00010694-199402000-00001 CrossRefGoogle Scholar
  58. White CE (2010) Stratigraphy of the Lower Paleozoic Goldenville and Halifax groups in southwestern Nova Scotia. Atlan Geol 46:136–154CrossRefGoogle Scholar
  59. White CE et al (2008) Geology of the Halifax Regional Municipality. In: MacDonald DR (ed) Mineral Resources Branch Report of Activities 2007, Nova Scotia Department of Natural Resources ME 2008-001:125–139Google Scholar
  60. WHO (2005) Radon and cancer. World Health Organization: fact sheet no. 291.
  61. Wichmann HE et al (2002) Domestic radon and lung cancer—current status including new evidence from Germany. Internation Congress Ser 1225:247–252CrossRefGoogle Scholar
  62. Yu KN, Koo VSY, Guan ZJ (2002) A simple and versatile 222Rn/220Rn exposure chamber. Nucl Instrum Methods Phys Res Sect A 481:749–755CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Kelsey E. O’Brien
    • 1
  • Dave Risk
    • 2
  • Daniel Rainham
    • 1
  • Anne Marie O’Beirne-Ryan
    • 1
  1. 1.Dalhousie UniversityHalifaxCanada
  2. 2.St Francis Xavier UniversityAntigonishCanada

Personalised recommendations