Nikolay Stoyanov, Stefan Dimovski
ABSTRACT. One of the many environmental problems resulting from electricity generation in thermal power plants is the release of large amounts of solid wastes (coal combustion products). In the absence of effective eco–friendly disposal practices, this waste is accumulated in the form of coal ash embankments or in the excavated parts of the open–cast mines. The so constituted big landfills and surface impoundments emit leachate emissions containing a wide range of conventional pollutants among which, by definition, sulphate ions (SO4) dominate. Using the computer program VS2DI, a numerical model is developed of the conditions for mass transport of pollutants (using the example of SO4) from the designed new embankments for deposition of non–hazardous industrial solid waste from TPP in the area of the internal embankments of Troyanovo–North open–cast mine, part of the Maritsa East Coal Mining Complex. The scheme of convective–diffusion mass transport is employed, taking into account reversible elimination (sorption–desorption), mechanical dispersion and mixing. On the basis of the developed model, a long–term prognosis (100 years) is made for the extent and the degree of subsurface contamination from the new embankments. Based on the model solutions, the retention capacity of the geological foundation and the risk of groundwater pollution are assessed.
Keywords: ecology, mass transport models, groundwater and soil contamination, landfills for solid waste from TPP, Maritsa East Coal Mining Complex
Stoyanov N., S. Dimovski
PROGNOSTIC MODEL OF SUBSURFACE CONTAMINATION CAUSED BY NEW EMBANKMENTS ON THE TERRITORY OF MARITSA EAST COAL MINING COMPLEX – CENTRAL SOUTHERN BULGARIA
DOI: 10.5281/zenodo.5594857
DOI: https://doi.org/10.58903/b15171919
References
1. Adams, E., L. Gelhar. 1992. Field study of dispersion in a heterogeneous aquifer. 2. Spatial moments analysis. – Water Resour. Res., 28 (12), 3293-3307, https://doi.org/10.1029/92WR01757
2. Bear, J. 1979. Hydraulics of groundwater. New York, McGraw-Hill, 569 p.
3. BP statistical review of world energy. 2019. 68th edition. 64 р. Available at: https://www.bp.com/content/dam/bp/business-sites/en/global/corporate/pdfs/energy-economics/statistical-review/bp-stats-review-2019-full-report.pdf
4. Bredenkamp, D. 1990. Quantitative estimation of groundwater recharge by means of a simple rainfall-recharge relationship. – In: Groundwater recharge. IAH Memoir, Vol 8. (Eds. Lerner, D., A. Issar, I. Simmers). Heise, 247−256.
5. Brooks, R., A. Corey. 1964. Hydraulic properties of porous media. – In: Hydrology Papers 3, Colorado State University. Fort Collins, 27 p.
6. Electric Power Research Institute (EPRI), 2012. Groundwater Quality Signatures for Assessing Potential Impacts from Coal Combustion Product Leachate. – Technical Report 1017923, 162 p.
7. Electric Power Research Institute (EPRI), 2015. Groundwater Monitoring Guidance for the Coal Combustion Residuals Rule. – Technical Report 3002006287, 172 p.
8. Haverkamp, R., M. Vauclin, J. Tovina, P. Wierenga, G. Vachaud. 1977. A comparison of numerical simulation models for one-dimensional infiltration. – Soil Science Society of America Journal, 41 (2), 285-294, https://doi.org/10.2136/sssaj1977.03615995004100020024x
9. Healy, R. W. 1990. Simulation of solute transport in variably saturated porous media with supplemental information on modifications to the US Geological Survey’s computer program VS2D. – USGS Numb. Ser., Water-Resour. Inv. Rep. 90-4025, Colorado, 125 p., https://doi.org/10.3133/wri904025
10. Hensel, B. 2016. Groundwater Monitoring and Data Analysis under the Coal Combustion Residuals Rule. – Coal Combustion and Gasification Products, 9, 37-41, https://doi.org/10.4177/1946-0198.9.2.37.1.
11. Hsieh, P., W. Wingle, R. W. Healy. 2000. VS2DI – A graphical software package for simulating fluid flow and solute or energy transport in variably saturated porous media. – USGS Numb. Ser., Water-Resour. Inv. Rep. 99-4130, 16 p.
12. Lappala, E., R. Healy, E. Weeks. 1987. Documentation of computer program VS2D to solve the equations of fluid flow in variably saturated porous media. USGS. – Water-Resour. Inv. Rep. 83-4099, Colorado, 184 p., https://doi.org/10.3133/wri834099
13. Nikolova, M., G. Gerganov, G. Sirashki, H. Sirashki, V. Ivanov. 2010. Vlianie na energiinia kompleks “Maritsa Istok” varhu proizvodstvoto na ekologichna zemedelska produktsia – Scientific Research Almanac, 13, 419-471 (in Bulgarian with English abstract)
14. Petrov, P. 2019. Oharakterizizrane na otpadatsite ot TETs “Sviloza” i tiahnoto ekologosaobrazno sahranenie i opolzotvoriavane. Avangard Prima, Sofia, 139 p. (in Bulgarian)
15. Rocha, A., J. Smith, D. Graves. 2017. Biogeochemistry: A novel approach to managing and marketing CCR. – Proc. of World of Coal Ash (WOCA) Conference in Lexington, KY, USA – May 9-11, 2017. p. 8
16. Rossi, C., J. Nimmo. 1994. Modeling of soil water retention from saturation to oven dryness. – Water Resource Research, 30 (3), 701-708.
17. Spitz, K., J. Moreno. 1996. A practical guide to groundwater and solute modeling. JW&S, NY, 460 p.
18. Stoyanov, N. 2019. Matematichesko modelirane v hidrogeologiyata. Chisleni 3D modeli po metoda na krainite razliki. Vanio Nedkov, Sofia, 246 p. (in Bulgarian)
19. Stoyanov, N. 2007. Migratsionni harakteristiki na tvardia otpadak (pepelinata), otdelian pri eksploatatsiata na TETs. – Annual of the University of Mining and Geology “St. Ivan Rilski”, 50, Part 1, 177-182 (in Bulgarian with English abstract)
20. Zheleva, E., M. Tsolova, B. Bogdanov. 2004. Novi ekologichni I tehnicheski problemi pri rekultivatsiata na narushenite tereni ot mini “Maritsa Istok” – Management and sustainable development, 1-2 (10), 323-328 (in Bulgarian with English abstract)
21. U.S. Environmental Protection Agency (US EPA), 2009. Statistical Analysis of Groundwater Monitoring Data at RCRA Facilities: Unified Guidance. – EPA 530/R-09-007, 884 p.
22. van Genuchten, M. Th. 1980. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. – Soil Science Society of America Journal, 44 (5), 892-898, https://doi.org/10.2136/sssaj1980.03615995004400050002x