Hydraulic and Geochemical Characteristics of a Geosynthetic Clay Liner Exhumed from an Exposed Composite Liner
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 150, Issue 5
Abstract
A geosynthetic clay liner (GCL) was exhumed from a composite liner (geomembrane over GCL containing granular sodium bentonite) in the base of a landfill cell after 12 years of atmospheric exposure. The GCL was altered appreciably during exposure, despite being overlain by a geomembrane. Water content, hydration, and bentonite erosion varied considerably along the slope. GCL samples from the top of the slope were dry, with visible bentonite granules comparable to those in a virgin GCL as if the bentonite had not hydrated. No substantial change in exchange complex or swell index (SI) occurred in samples from the top of the slope, and hydraulic conductivity of these samples to water was low (). GCL samples from the toe of the slope varied considerably, from moist and soft to dry and cracked, but all had undergone hydration, and had low SI, a small mole fraction of monovalent cations in the exchange complex, and high hydraulic conductivity ( or higher). Bentonite in GCL samples from midslope had a cracked structure commonly observed in GCLs that have undergone wet–dry cycling. Midslope GCLs typically had hydraulic conductivity greater than . A sample from the top of the slope from a location near a GCL panel separation was comparable to other samples from the top of the slope. GCL samples from the anchor trench differed considerably, being very permeable or having low hydraulic conductivity. Hydraulic conductivity was strongly correlated with SI; GCL samples with were highly permeable, and those with were comparable to a virgin GCL. The variation in SI was related directly to replacement of sodium by calcium in the exchange complex of the bentonite. Hydraulic conductivity also was affected by the thinning of the GCL.
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Data Availability Statement
All data that support the findings of this study are available from the corresponding author on request.
Acknowledgments
Financial support for this study was provided by the US Department of Energy (DOE) under cooperative agreement DE-FC01-06EW07053 (Consortium for Risk Evaluation with Stakeholder Participation III) and the Global Waste Research Institute at California Polytechnic State University. Waste Connections Inc. and Cold Canyon Landfill are acknowledged for allowing site access and sampling of the liner system. Amro El Badawy, Kyle O’Hara, John Buringa, Sean Herman, and Spencer Jemes assisted with sampling. Jonathan Owen, Anthony Trujillo, and Brett Crews assisted with laboratory testing. Med Stop Urgent Care in San Luis Obispo, California provided the X-ray imaging for the study.
References
ASTM. 2018a. Standard practice for obtaining samples of geosynthetic clay liners. ASTM D6072. West Conshohocken, PA: ASTM.
ASTM. 2018b. Standard specification for reagent water. ASTM D1193. West Conshohocken, PA: ASTM.
ASTM. 2018c. Standard test method for evaluation of hydraulic properties of geosynthetic clay liners permeated with potentially incompatible aqueous solutions. ASTM D6766. West Conshohocken, PA: ASTM.
ASTM. 2018d. Standard test method for measuring the exchange complex and cation exchange capacity of inorganic fine-grained soils. ASTM D7503. West Conshohocken, PA: ASTM.
ASTM. 2018e. Standard test method for measuring mass per unit area of geosynthetic clay liners. ASTM D5993. West Conshohocken, PA: ASTM.
ASTM. 2018f. Standard test method for swell index of clay mineral component of geosynthetic clay liners. ASTM D5890. West Conshohocken, PA: ASTM.
ASTM. 2018g. Standard test methods for laboratory determination of water (moisture) content of soil and rock by mass. ASTM D2216. West Conshohocken, PA: ASTM.
ASTM. 2018h. Standard test methods for measurement of hydraulic conductivity of saturated porous materials using a flexible wall permeameter. ASTM D5084. West Conshohocken, PA: ASTM.
Azad, F., R. Rowe, A. El-Zein, and D. Airey. 2011. “Laboratory investigation of thermally induced desiccation of GCLs in double composite liner systems.” Geotext. Geomembr. 29 (6): 534–543. https://doi.org/10.1016/j.geotexmem.2011.07.001.
Beck, H., N. Zimmermann, T. McVicar, N. Vergopolan, A. Berg, and E. Wood. 2018. “Present and future Köppen-Geiger climate classification maps at 1-km resolution.” Sci. Data 5 (1): 180214. https://doi.org/10.1038/sdata.2018.214.
Benson, C., et al. 2013. “Impact of subgrade water content on cation exchange and hydraulic conductivity of geosynthetic clay liners in composite barriers.” In Coupled phenomena in environmental geotechnics, edited by M. Manassero, 1–6. Boca Raton, FL: CRC Press.
Benson, C., I. Kucukkirca, and J. Scalia. 2010. “Properties of geosynthetics exhumed from a final cover at a solid waste landfill.” Geotext. Geomembr. 28 (6): 536–546. https://doi.org/10.1016/j.geotexmem.2010.03.001.
Benson, C., and S. Meer. 2009. “Relative abundance of monovalent and divalent cations and the impact of desiccation on geosynthetic clay liners.” J. Geotech. Geoenviron. Eng. 135 (3): 349–358. https://doi.org/10.1061/(ASCE)1090-0241(2009)135:3(349).
Benson, C., P. Thorstad, H. Jo, and S. Rock. 2007. “Hydraulic performance of geosynthetic clay liners in a landfill final cover.” J. Geotech. Geoenviron. Eng. 133 (7): 814–827. https://doi.org/10.1061/(ASCE)1090-0241(2007)133:7(814).
Brachman, R., A. Rentz, R. Rowe, and W. Take. 2014. “Classification and quantification of downslope erosion from a geosynthetic clay liner (GCL) when covered only by a black geomembrane.” Can. Geotech. J. 52 (4): 395–412. https://doi.org/10.1139/cgj-2014-0241.
Bradshaw, S., and C. Benson. 2014. “Effect of municipal solid waste leachate on hydraulic conductivity and exchange complex of geosynthetic clay liners.” J. Geotech. Geoenviron. Eng. 140 (4): 4013038. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001050.
Bradshaw, S., C. Benson, and T. Rauen. 2015. “Hydraulic conductivity of geosynthetic clay liners to recirculated municipal solid waste leachates.” J. Geotech. Geoenviron. Engineering 142 (2): 04015074. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001387.
Bradshaw, S., C. Benson, and J. Scalia IV. 2013. “Hydration and cation exchange during subgrade hydration and effect on hydraulic conductivity of geosynthetic clay liners.” J. Geotech. Geoenviron. Eng. 139 (4): 526–538. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000793.
Chen, J., C. Benson, and T. Edil. 2018. “Hydraulic conductivity of geosynthetic clay liners with sodium bentonite to coal combustion product leachates.” J. Geotech. Geoenviron. Eng. 144 (3): 04018008. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001844.
EPA. 2014. “Method 6020B, inductively coupled plasma-mass spectrometry, Revision 2.” In Test methods for evaluating solid waste: Physical/chemical methods compendium (SW-846). Washington, DC: USEPA.
Fan, J., and R. Rowe. 2023. “Effect of geosynthetic component characteristics on the potential for GCL internal erosion.” Geotext. Geomembr. 51 (4): 85–94. https://doi.org/10.1016/j.geotexmem.2023.03.006.
Hanson, J., and N. Yeşiller. 2020. “Assessment of condition of an uncovered geosynthetic landfill bottom liner system.” In Proc., Geosynthetics 2019, 10–19. St. Paul, MN: Industrial Fabrics Association International.
Hou, J., R. Sun, and C. Benson. 2023. “Hydrodynamic assessment of bentonite granule size and swelling on hydraulic conductivity of geosynthetic clay liners.” Geotext. Geomembr. 51 (5): 93–103. https://doi.org/10.1016/j.geotexmem.2023.05.002.
James, A., D. Fullerton, and R. Drake. 1997. “Field performance of GCL under ion exchange conditions.” J. Geotech. Geoenviron. Eng. 123 (10): 897–901. https://doi.org/10.1061/(ASCE)1090-0241(1997)123:10(897).
Jo, H. Y., T. Katsumi, C. H. Benson, and T. B. Edil. 2001. “Hydraulic conductivity and swelling of nonprehydrated GCLs permeated with single-species salt solutions.” J. Geotech. Geoenviron. Eng. 127 (7): 557–567. https://doi.org/10.1061/(ASCE)1090-0241(2001)127:7(557).
Kolstad, D. C., C. H. Benson, and T. B. Edil. 2004. “Hydraulic conductivity and swell of nonprehydrated geosynthetic clay liners permeated with multispecies inorganic solutions.” J. Geotech. Geoenviron. Eng. 130 (12): 1236–1249. https://doi.org/10.1061/(ASCE)1090-0241(2004)130:12(1236).
Lin, L.-C., and C. H. Benson. 2000. “Effect of wet-dry cycling on swelling and hydraulic conductivity of GCLs.” J. Geotech. Geoenviron. Eng. 126 (1): 40–49. https://doi.org/10.1061/(ASCE)1090-0241(2000)126:1(40).
Makusa, G. P., S. L. Bradshaw, E. Berns, C. H. Benson, and S. Knutsson. 2014. “Freeze-thaw cycling and the hydraulic conductivity of geosynthetic clay liners concurrent with cation exchange.” Can. Geotech. J. 51 (6): 591–598. https://doi.org/10.1139/cgj-2013-0127.
McBride, M. 1994. Environmental chemistry of soils. New York: Oxford University Press.
Meer, S. R., and C. H. Benson. 2007. “Hydraulic conductivity of geosynthetic clay liners exhumed from landfill final covers.” J. Geotech. Geoenviron. Eng. 13 (5): 550–563. https://doi.org/10.1061/(ASCE)1090-0241(2007)133:5(550).
Moore, D., and R. Reynolds. 1989. X-ray diffraction and the identification and analysis of clay minerals. New York: Oxford University Press.
Nassar, I., R. Horton, and A. Globus. 1997. “Thermally induced water transfer in salinized unsaturated soil.” Soil Sci. Soc. Am. J. 61 (5): 1293–1299. https://doi.org/10.2136/sssaj1997.03615995006100050002x.
Petrov, R., R. Rowe, and R. Quigley. 1997. “Selected factors influencing GCL hydraulic conductivity.” J. Geotech. Geoenviron. Eng. 123 (8): 683–695. https://doi.org/10.1061/(ASCE)1090-0241(1997)123:8(683).
Rowe, R. 2020. “Geosynthetic clay liners: Perceptions and misconceptions.” Geotext. Geomembr. 48 (2): 137–156. https://doi.org/10.1016/j.geotexmem.2019.11.012.
Rowe, R., R. Brachman, W. Take, A. Rentz, and L. E. Ashe. 2016. “Field and laboratory observations of down-slope bentonite migration in exposed composite liners.” Geotext. Geomembr. 44 (5): 686–706. https://doi.org/10.1016/j.geotexmem.2016.05.004.
Rowe, R., J. Garcia, R. Brachman, and M. Hosney. 2023. “Moisture uptake and loss of GCLs subjected to thermal cycles from silty sand subgrade.” Geosynth. Int. 30 (2): 113–128. https://doi.org/10.1680/jgein.21.00049.
Rowe, R., and S. Hamdan. 2021. “Effect of wet-dry cycles on standard & polymer-amended GCLs in covers subjected to flow over the GCL.” Geotext. Geomembr. 49 (5): 1165–1175. https://doi.org/10.1016/j.geotexmem.2021.03.010.
Rowe, R., and C. Orsini. 2003. “Effect of GCL and subgrade type on internal erosion in GCLs under high gradient.” Geotext. Geomembr. 21 (1): 1–24. https://doi.org/10.1016/S0266-1144(02)00036-5.
Rowe, R., W. Take, R. Brachman, and A. Rentz. 2014. “Field observations of moisture migration on GCLs in exposed liners.” In Proc., 10th Int. Conf. on Geosynthetics, ICG 2014, 7–17. Austin, TX: International Geosynthetics Society.
Ruhl, J., and D. Daniel. 1997. “Geosynthetic clay liners permeated with chemical solutions and leachates.” J. Geotech. Geoenviron. Eng. 123 (4): 369–381. https://doi.org/10.1061/(ASCE)1090-0241(1997)123:4(369).
Scalia, J., and C. Benson. 2010. “Effect of permeant water on the hydraulic conductivity of exhumed GCLs.” Geotech. Test. J. 33 (3): 1–11. https://doi.org/10.1520/GTJ102609.
Scalia, J., and C. Benson. 2011. “Hydraulic conductivity of geosynthetic clay liners exhumed from landfill final covers with composite barriers.” J. Geotech. Geoenviron. Eng. 137 (1): 1–13. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000407.
Scalia, J., C. Benson, W. Albright, B. Smith, and X. Wang. 2017. “Properties of barrier components in a composite cover after 14 years of service and differential settlement.” J. Geotech. Geoenviron. Eng. 143 (9): 1–11. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001744.
Scalia, J., G. Bohnhoff, C. Shackelford, C. Benson, K. Sample-Lord, M. A. Malusis, and W. J. Likos. 2018. “Enhanced bentonites for containment of inorganic waste leachates by GCLs.” Geosynth. Int. 25 (4): 392–411. https://doi.org/10.1680/jgein.18.00024.
Shackelford, C., C. Benson, T. Katsumi, T. Edil, and L. Lin. 2000. “Evaluating the hydraulic conductivity of GCLs permeated with non-standard liquids.” Geotext. Geomembr. 18 (2–4): 133–161. https://doi.org/10.1016/S0266-1144(99)00024-2.
Take, W., R. Brachman, and R. Rowe. 2015. “Observations of bentonite erosion from solar-driven moisture migration in GCLs covered only by a black geomembrane.” Geosynth. Int. 22 (1): 78–92. https://doi.org/10.1680/gein.14.00033.
Tian, K., C. Benson, and W. Likos. 2016. “Hydraulic conductivity of geosynthetic clay liners to low-level radioactive waste leachate.” J. Geotech. Geoenviron. Eng. 142 (8): 04016037. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001495.
Tian, K., C. Benson, N. Yeşiller, and J. Hanson. 2019. “Evaluation of a HDPE geomembrane from a composite liner after 12 years of atmospheric exposure.” In Proc., Geosynthetics 2019, 522–527. St. Paul, MN: Industrial Fabrics Association International.
Williams, T. 2018. “Hydraulic properties of geosynthetic clay liners.” M.S. thesis, School of Engineering and Applied Science, Univ. of Virginia.
Yeşiller, N., and C. Shackelford. 2011. “Chapter 13: Geoenvironmental engineering.” In Geotechnical engineering handbook, 13.1–13.61, edited by B. Das. Plantation, FL: J. Ross.
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© 2024 American Society of Civil Engineers.
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Received: Aug 16, 2023
Accepted: Nov 21, 2023
Published online: Feb 28, 2024
Published in print: May 1, 2024
Discussion open until: Jul 28, 2024
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