Journal of Civil Engineering and Science                 
Journal of Civil Engineering and Science(JCES)
ISSN:2227-4634 (Print)
ISSN:2227-4626(Online)
Website: www.academicpub.org/jces/
Risk-Based Characterization for Vapour Intrusion at a Conceptual Brownfields Site: Part 1. Data Worth and Prediction Uncertainty
Full Paper(PDF, 5966KB)
Abstract:
The focus of this paper is to present a methodology to assimilate soil core permeability and trichloroethylene (TCE) soil gas concentration data, and then to assess their worth in reducing prediction uncertainty with a numerical model. The specific problem involves a residential development impacted by indoor air exposure of TCE contamination originating from a groundwater plume. Three metrics are used to quantify the prediction uncertainty, namely: the ability to accurately predict the indoor air concentration within the houses at any point in time; the ability to reduce the standard deviation of predicted indoor air concentration within these houses; and, the ability to accurately forecast the probability of indoor air concentrations exceeding a regulatory limit. The data assimilation methodology involves generating multiple realizations of heterogeneous permeability fields conditioned upon a geostatistical analysis of the borehole data, combined with a discrete static Kalman filter to assimilate actual soil gas concentration data, to estimate soil gas and indoor air concentrations at those locations where the developer does not have any data but liability. The worth of using progressively more permeability and soil gas concentration data is quantified on the basis that it provides a statistically significant improvement in the three metrics used to measure prediction uncertainty.
Keywords:Brownfields; Vapour Intrusion; Prediction Uncertainty; Data Worth; Kalman Filter; Probability of Exceedance
Author: Xiaomin Wang1, Andre J.A. Unger1, Beth L. Parker2
1.Department of Earth and Environmental Sciences, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada
2.School of Engineering, University of Guelph, 50 Stone Road East Guelph, Ontario, Canada
References:
  1. D.W. Hyndman, F.D. Day-Lewis FD, and K. Singha, “Subsurface hydrology: data integration for properties and processes,” American Geophysical Union, USA, 2007.
  2. M.A. Turcke and B.H. Kueper, “Geostatistical analysis of the Borden aquifer hydraulic conductivity field,” Journal of Hydrology, vol. 178(1-4), pp. 223-240, 1996.
  3. C.D. Laird, L.T. Biegler, B.G. van Bloemen Waanders, and R.A. Bartlett, “Contamination source determination for water networks,” Journal of Water Resources Planning and Management, vol. 131(2), pp. 125-134, 2005.
  4. S. Lesage and R.E. Jackson, Groundwater contamination and analysis at hazardous waste sites, New York, USA, 1992.
  5. ITRC (Interstate Technology & Regulatory Council), “Vapor Intrusion Pathway: A Practical Guideline. VI-1,” Interstate Technology & Regulatory Council, Vapor Intrusion Team, Washington, D.C, 2007.
  6. B. Longino, “DNAPL source zone characterization and remediation: an ongoing challenge,” Groundwater Resources Association of California (GRAC), 2005. http://www.grac.org/dnaplsummary.asp (accessed 31 July 2014).
  7. D.L. Russell, Remediation manual for petroleum contaminated sites, Lancaster, PA, 1992.
  8. C.H. Ward, J.A. Cherry, and M.R. Scalf, Subsurface restoration, Chelsea, MI, 1997.
  9. NRTEE (National Round Table on the Environment and the Economy Canada), “Cleaning up the Past, Building the Future: A National Brownfield Redevelopment Strategy for Canada,” 2011. http://toronto350.org/NRTEE/cleaning-up-the-past.pdf (accessed 31 July 2014).
  10. UK Environment Agency, “Brownfield land redevelopment: position statement,” Environmental Agency, 2003. http://webarchive.nationalarchives.gov.uk/20140328084622/http://www.environment-agency.gov.uk/research/library/position/41237.aspx (accessed 17 June 2014).
  11. US Environmental Protection Agency (EPA), “A sustainable brownfields model framework,” Publication Number: EPA-500-R-99-001, January 1999.
  12. X. Wang, A.J.A. Unger, and B.L. Parker, “Simulating an exclusion zone for vapour intrusion of TCE from groundwater into indoor air,” Journal of Contaminant Hydrology, vol. 140-141, pp. 124-138, 2012.
  13. S. Yu, A.J.A. Unger, and B. Parker, “Simulating the fate and transport of TCE from groundwater to indoor air,” Journal of Contaminant Hydrology, vol. 107(3-4), pp. 140-161, 2009.
  14. ASTM (American Society for Testing and Materials Standard), “Standard specification for biodiesel fuel (B100) blend stock for distillate fuels, method D6751,” ASTM International, West Conshohocken, PA, DOI: 10.1520/D6751-02, 2008.
  15. NYSDOH (New York State Department of Health), “Fact sheet: February 2005 ‘Trichloroethene (TCE) in indoor and outdoor air’,” 2005. http://www.health.state.ny.us/environmental/investigations/soil_gas/svi_guidance/docs/fs_tce.pdf (accessed 17 June 2014).
  16. OEHHA-CEPA (Office of Environmental Health Hazard Assessment – California Environmental Protection Agency), “Occupational health hazard risk assessment project for California: Identification of chemicals of concern, possible risk assessment methods, and examples of health protective occupational air concentrations,” Reproductive and Cancer Hazard Assessment Branch, 2007. http://www.cdph.ca.gov/programs/hesis/Documents/riskreport.pdf (accessed 17 June 2014).
  17. R. Freeze, B. James, J. Massmann, T. Sperling, and L. Smith, “Hydrogeological decision analysis: 4. The concept of data worth and its use in the development of site investigation strategies,” Ground Water, vol. 30(4), pp. 574-588, 1992.
  18. J. Massmann and R.A. Freeze, “Groundwater contamination from waste management sites: The interaction between risk-based engineering design and regulatory policy. I. methodology,” Water Resources Research, vol. 23(2), pp. 351-367, 1987a.
  19. J. Massmann and R.A. Freeze, “Groundwater contamination from waste management sites: The interaction between risk-based engineering design and regulatory policy. II. Results,” Water Resources Research, vol. 23(2), pp. 368-380, 1987b.
  20. S. Yu, A.J.A. Unger, B. Parker, and T. Kim, “Allocating risk capital for a brownfields redevelopment project under hydrogeological and financial uncertainty,” Journal of Environmental Management, vol. 100(0), pp. 96-108, 2012.
  21. P.A. Forsyth, “A positivity preserving method for simulation of steam injection for NAPL site remediation,” Advances in Water Resources, vol. 16(6), pp. 351-370, 1993.
  22. P.A. Forsyth, A.J.A. Unger, and E.A. Sudicky, “Nonlinear iteration methods for nonequilibrium multiphase subsurface flow,” Advances in Water Resources, vol. 21(6), pp. 433-449, 1998.
  23. A.J.A. Unger, P.A. Forsyth, and E.A. Sudicky, “Variable spatial and temporal weighting schemes for use in multi-phase compositional problems,” Advances in Water Resources, vol. 19(1), pp. 1-27, 1996.
  24. Y. Yao, R. Shen, K.G. Pennell, and E.M. Suuberg, “A review of vapor intrusion models,” Environmental Science and Technology, vol. 47(6), pp. 2457-2470, 2013.
  25. J.D. Bredehoeft, “From models to performance assessment: The conceptualization problem,” Ground Water, vol. 41(5), pp. 571-577, 2003.
  26. J.D. Bredehoeft, “The conceptualization model problem – surprise,” Hydrogeology Journal, vol. 13(1), pp. 37-46, 2005.
  27. S.P. Neuman, “Maximum likelihood bayesian averaging of uncertain model predictions,” Stochastic Environmental Research and Risk Assessment, vol. 17(5), pp. 291-305, 2003.
  28. J.C. Refsgaard, J.P. van der Sluijs, J. Brown, and P. van der Keur, “A framework for dealing with uncertainty due to model structure error,” Advances in Water Resources, vol. 29(11), pp. 1586-1597, 2006.
  29. K.C. Abbaspour, M.T. Van Genuchten, R. Schulin, and E. Schläppi, “A sequential uncertainty domain inverse procedure for estimating subsurface flow and transport parameters,” Water Resources Research, vol. 33(8), pp. 1879-1892, 1997.
  30. WW-G. Yeh, “Review of parameter identification procedures in groundwater hydrology: The inverse problem,” Water Resources Research, vol. 22(2), pp. 95-108, 1986.
  31. R.A. Marryott, “Optimal ground-water remediation design using multiple control technologies,” Ground Water, vol. 34(3), pp. 425-433, 1996.
  32. H.I. Essaid and K.M. Hess, “Monte Carlo simulations of multiphase flow incorporating spatial variability of hydraulic properties,” Groundwater, vol. 31(1), pp. 123-143, 1993.
  33. Y. Zhang, G.F. Pinder, and G.S. Herrera, “Least cost design of groundwater quality monitoring networks,” Water Resources Research, vol. 41(8), pp. 1-12, 2005.
  34. R. Andricevic, “Cost-effective network design for groundwater flow monitoring,” Stochastic Hydrology and Hydraulics, vol. 4(1), pp. 27-41, 1990.
  35. R. Andricevic, “Coupled withdrawal and sampling designs for groundwater supply models,” Water Resources Research, vol. 29(1), pp. 5-16, 1993.
  36. Z. Dokou and G.F. Pinder, “Extension and field application of an integrated DNAPL source identification algorithm that utilizes stochastic modeling and a kalman filter,” Journal of Hydrology, vol. 398(3-4), pp. 277-291, 2011.
  37. W.D. Graham and D.B. McLaughlin, “Stochastic analysis of nonstationary subsurface solute transport. 2. Conditional moments,” Water Resources Research, vol. 25(11), pp. 2331-2355, 1989.
  38. W.D. Graham and D.B. McLaughlin, “A stochastic model of solute transport in groundwater: Application to the Borden, Ontario, tracer test,” Water Resources Research, vol. 27(6), pp. 1345-1359, 1991.
  39. G.S. Herrera, “Cost effective groundwater quality sampling network design,” PhD dissertation, University of Vermont, 1998.
  40. OME (Ontario Ministry of the Environment), “Guideline for use at contaminated sites in Ontario,” Ministry of Environment and Energy, 1997.
  41. OMMAH (Ontario Ministry of Municipal Affairs and Housing), “A practical guide to brownfields redevelopment in Ontario,” 2007. http://www.mah.gov.on.ca/AssetFactory.aspx?did=4995 (accessed 17 June 2014).
  42. G. Dagan, “Solute transport in heterogeneous porous formations,” Journal of Fluid Mechanics, vol. 145, pp. 151-177, 1984.
  43. M.J.L. Robin, A.L. Gutjahr, E.A. Sudicky, and J.L. Wilson, “Cross-correlated random field generation with the direct Fourier transform method,” Water Resources Research, vol. 29(7), pp. 2385-2397, 1993.
  44. E.A. Sudicky, “Natural gradient experiment on solute transport in a sand aquifer: spatial variability of hydraulic conductivity and its role in the dispersion process,” Water Resources Research, vol. 22(13), pp. 2069-2082, 1986.
  45. A.D. Woodbury and E.A. Sudicky, “The Geostatistical Characteristics of the Borden Aquifer,” Water Resources Research, vol. 27(4), pp. 533-546, 1991.
  46. K.M. Hess, S.H. Wolf, and M.A. Celia, “Large scale natural gradient tracer test in sand and gravel, Cape Cod, Massachusetts: 3. Hydraulic conductivity and calculated macrodispersivities,” Water Resources Research, vol. 28(8), pp. 2011-2027, 1992.
  47. R.A. Freeze, H. Massmann, L. Smith, T. Sperling, and B. James, “Hydrogeological decision analysis: 1. A framework,” Ground Water, vol. 28(5), pp. 738-766, 1990.
  48. R.J. Barnes, “The variogram sill and the sample variance,” Mathematical Geology, vol. 23(4), pp. 673-678, 1991.
  49. P.A. Rogerson, E. Delmelle, R. Batta, M. Akella, A. Blatt, and G. Wilson, “Optimal sampling design for variables with varying spatial importance,” Geographical Analysis, vol. 36(2), pp. 177-194, 2004.
  50. J.W. Van Groenigen, “The influence of variogram parameters on optimal sampling schemes for mapping by kriging,” Geoderma, vol. 97(3-4), pp. 223-236, 2000.
  51. W.A. McGrath and G.F. Pinder, “Search strategy for groundwater contaminant plume delineation,” Water Resources Research, vol. 39(10), SBH141-SBH1412, 2003.
  52. A. Gelb, Applied optimal estimation, Cambridge, Massachusetts, 1974.
  53. D.L. Marrin and G.M. Thompson, “Gaseous behavior of TCE overlying a contaminated aquifer,” Ground Water, vol. 25(11), pp. 21-27, 1987.
  54. X. Wang, “A least-cost strategy for evaluating a brownfields redevelopment project subject to indoor air exposure regulations,” PhD dissertation, University of Waterloo, 2012.