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Title: Algebraic expressions for estimating the impact depths of a surface barrier over a homogeneous soil

Abstract

Engineered surface barriers are used to isolate subsurface contaminants for effective long-term containment of municipal solid waste, other nonhazardous solid and liquid waste, hazardous and toxic wastes, and radioactive waste. The impact depths of a surface barrier are affected by the pre-barrier recharge rate and the properties of the soil beneath the barrier. In this paper, the pore-size-specific (PSS) water velocity is defined and an algebraic expression of PSS velocity is derived based on the stream tube concept and the Brooks and Corey hydraulic retention model. Algebraic expressions are developed to estimate drainage velocities and barrier impact depths after the emplacement of a surface barrier. Four impact depth terms are used to convey the protective effect: drainage front, average drainage, the location with 50% impact, and drainage tail. The drainage front depth is the deepest point at which the barrier has a detectable impact at a specific time (also called the near zero-impact depth). The average-impact depth is the depth at which average drainage occurs. At the 50% impact depth, the water flux rate is reduced by half because of the surface barrier. Lastly, the drainage tail depth (also called the full-impact depth) is the deepest depth at which themore » water conditions above it are in equilibrium with the barrier. The algebraic expressions show that the average-impact depth is no more than 1/3 of near zero-impact depth, while the 50% impact depth is slightly larger than 1/2 of the near zero-impact depth. The full-impact depth, depending on the final recharge rate from the surface barrier, is usually much smaller than the other impact depths. These differences lead to a very large transition zone beneath a surface barrier. Numerical simulations were conducted to replicate the same conditions. The numerical results corroborated the analytical models by predicting very similar water content profiles and near zero-, average-, 50%, and full-impact depths. The algebraic expressions provided in this paper are useful for quickly identifying sites where the depth of the existing contaminants could be beyond the protection of a surface barrier.« less

Authors:
ORCiD logo [1]
  1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1606199
Report Number(s):
PNNL-SA-141144
Journal ID: ISSN 1539-1663
Grant/Contract Number:  
AC05-76RL01830
Resource Type:
Accepted Manuscript
Journal Name:
Vadose Zone Journal
Additional Journal Information:
Journal Volume: 19; Journal Issue: 1; Journal ID: ISSN 1539-1663
Publisher:
Soil Science Society of America
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; Unsaturated Flow; vadose zone; Modeling & Simulation; Remediation

Citation Formats

Zhang, Zhuanfang. Algebraic expressions for estimating the impact depths of a surface barrier over a homogeneous soil. United States: N. p., 2020. Web. https://doi.org/10.1002/vzj2.20003.
Zhang, Zhuanfang. Algebraic expressions for estimating the impact depths of a surface barrier over a homogeneous soil. United States. https://doi.org/10.1002/vzj2.20003
Zhang, Zhuanfang. Sat . "Algebraic expressions for estimating the impact depths of a surface barrier over a homogeneous soil". United States. https://doi.org/10.1002/vzj2.20003. https://www.osti.gov/servlets/purl/1606199.
@article{osti_1606199,
title = {Algebraic expressions for estimating the impact depths of a surface barrier over a homogeneous soil},
author = {Zhang, Zhuanfang},
abstractNote = {Engineered surface barriers are used to isolate subsurface contaminants for effective long-term containment of municipal solid waste, other nonhazardous solid and liquid waste, hazardous and toxic wastes, and radioactive waste. The impact depths of a surface barrier are affected by the pre-barrier recharge rate and the properties of the soil beneath the barrier. In this paper, the pore-size-specific (PSS) water velocity is defined and an algebraic expression of PSS velocity is derived based on the stream tube concept and the Brooks and Corey hydraulic retention model. Algebraic expressions are developed to estimate drainage velocities and barrier impact depths after the emplacement of a surface barrier. Four impact depth terms are used to convey the protective effect: drainage front, average drainage, the location with 50% impact, and drainage tail. The drainage front depth is the deepest point at which the barrier has a detectable impact at a specific time (also called the near zero-impact depth). The average-impact depth is the depth at which average drainage occurs. At the 50% impact depth, the water flux rate is reduced by half because of the surface barrier. Lastly, the drainage tail depth (also called the full-impact depth) is the deepest depth at which the water conditions above it are in equilibrium with the barrier. The algebraic expressions show that the average-impact depth is no more than 1/3 of near zero-impact depth, while the 50% impact depth is slightly larger than 1/2 of the near zero-impact depth. The full-impact depth, depending on the final recharge rate from the surface barrier, is usually much smaller than the other impact depths. These differences lead to a very large transition zone beneath a surface barrier. Numerical simulations were conducted to replicate the same conditions. The numerical results corroborated the analytical models by predicting very similar water content profiles and near zero-, average-, 50%, and full-impact depths. The algebraic expressions provided in this paper are useful for quickly identifying sites where the depth of the existing contaminants could be beyond the protection of a surface barrier.},
doi = {10.1002/vzj2.20003},
journal = {Vadose Zone Journal},
number = 1,
volume = 19,
place = {United States},
year = {2020},
month = {2}
}

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Works referenced in this record:

Relative Permeability Calculations From Pore Size Distribution Data
journal, March 1953

  • Burdine, N. T.
  • Journal of Petroleum Technology, Vol. 5, Issue 03
  • DOI: 10.2118/225-G

Estimating Soil Hydraulic Parameters of a Field Drainage Experiment Using Inverse Techniques
journal, May 2003

  • Zhang, Z. F.; Ward, A. L.; Gee, G. W.
  • Vadose Zone Journal, Vol. 2, Issue 2
  • DOI: 10.2113/2.2.201

Simple Method for Predicting Drainage from Field Plots
journal, November 1980


Postconstruction Changes in the Hydraulic Properties of Water Balance Cover Soils
journal, April 2007


Field Water Balance of Landfill Final Covers
journal, November 2004

  • Albright, William H.; Benson, Craig H.; Gee, Glendon W.
  • Journal of Environmental Quality, Vol. 33, Issue 6
  • DOI: 10.2134/jeq2004.2317

Design and performance evaluation of a 1000-year evapotranspiration-capillary surface barrier
journal, February 2017

  • Zhang, Zhuanfang Fred; Strickland, Christopher E.; Link, Steven O.
  • Journal of Environmental Management, Vol. 187
  • DOI: 10.1016/j.jenvman.2016.11.007

Field Soil Water Retention of the Prototype Hanford Barrier and Its Variability with Space and Time
journal, August 2015


Biointrusion of Protective Barriers at Hazardous Waste Sites
journal, May 1998


Field Hydrology of Water Balance Covers for Waste Containment
journal, February 2015

  • Apiwantragoon, Preecha; Benson, Craig H.; Albright, William H.
  • Journal of Geotechnical and Geoenvironmental Engineering, Vol. 141, Issue 2
  • DOI: 10.1061/(ASCE)GT.1943-5606.0001195

Field Evaluation of Alternative Earthen Final Covers
journal, January 2001

  • Benson, C.; Abichou, T.; Albright, W.
  • International Journal of Phytoremediation, Vol. 3, Issue 1
  • DOI: 10.1080/15226510108500052

Impact of land use and land cover change on groundwater recharge and quality in the southwestern US
journal, October 2005


Fly ash as a permeable cap for tailings management: pedogenesis in bauxite residue tailings
journal, November 2014


Assessing the Performance of Evapotranspiration Covers for Municipal Solid Waste Landfills in Northwestern Ohio
journal, April 2011