Assessments of Internal Erosion in a Landfill Due to Changes in Groundwater Level

Soil erosion has special consequences for landfills that are more serious than those found at conventional construction sites. Different potential heads between two sides of a landfill and the subsequent movement of water through pores within the soil body could trigger the soil erosion and construction instability. Such condition was encountered in a landfill project in the southern part of Norway. To check the risk of internal erosion due changes in the groundwater level (because of seasonal flooding in the river), a series of numerical simulations by means of Geo-Seep software were conducted. Output of this study provides a total picture of the landfill stability, possibilities of erosions and necessary measures to prevent or reduce the risk for the landfill operator.

• Siamak Feizi
• Gunvor Baardvik

• Erosion
• seepage
• landfill
• stability.

[1] Vaverkova, M. D.: Landfill Impacts on the Environment—Reviews, Geosciences, 9, 431; doi: 10.3390, 2019.
[2] Thomaz, E. L. and Luiz, J. C.: Soil loss, soil degradation and rehabilitation in a degraded land area in Guarapuava (Brazil). Land Degrad. Dev., 23, 72-81, 2012.
[3] Bai, X. Y., Wang, S. J., and Xiong, K. N.: Assessing spatialtemporal evolution processes of karst rocky desertification land: indications for restoration strategies. Land Degrad. Dev., 24, 47–56, 2013.
[4] Chen, X.W., Tsz-Fung, Wong, J., Mo,W. Y., Man, Y.B.,Wang-Wai, Ng. Ch., and Wong M. H.: Ecological Performance of the Restored South east New Territories 8SENT) Landfill in Hong Kong (2000–2012). Land Degrad. Dev., 1, 1–13, doi:10.1002/ldr.2366, 2015.
[5] Chu-Agor, M.L.; Fox, G.A.; Cancienne, R.M.; Wilson, G.V. Seepage caused tension failures and erosion undercutting of hillslopes. J. Hydrol. 359, 247–259, 2008.
[6] Fox, G.A.; Wilson, G.V. The role of subsurface flow in hillslope and stream bank erosion: A review. Soil Sci. Soc. Am. J. 2010, 74, 717–733.
[7] Terzaghi, K. Der Grundbruch an Stauwerken und Seine Verhütung. Wasserkraft, 17, 445–449, 1922.
[8] Tschugajew, R., A new method for the calculation of seepage flow. (in Russian), Gidrotechniceskoe stroitel’stvo 26, Moscow, 1956.
[9] Novak, P., Moffat, A.I.B., Nalluri, C., and Narayanan, R., Hydraulic Structures, 3rd edition, Spon, London/New York, 2001.
[10] Zhe Huang, Yuchuan Bai Haijue Xu, Yufen Cao and Xiao Hu, A Theoretical Model to Predict the Critical Hydraulic Gradient for Soil Particle Movement under Two-Dimensional Seepage Flow, Water 2017, 9, 828; doi:10.3390/w9110828, 2017.
[11] Geo-Studio program, Seep, 2019 revision.
[12] NGI- Inhouse data base for the landfill project, 2021