Document Type : Research Paper

Authors

1 Department of Mining Engineering, School of Geology and Mining Engineering, University of Ngaoundere, Meiganga, Cameroon.

2 Department of Environmental Science, National Advanced School of Engineering, University of Maroua, Maroua, Cameroon.

3 Far North Court of Appeal, Ministry of Justice, Keepers of the Seals, Kaéle, Cameroon. Department of Economics, Management and Mining, Oil and Gas Legislation, Petroleum and Gas Engineering, National Advanced School of Mines and Petroleum Industries, University of Maroua, Cameroon.

4 Department of Hydraulics and Water Management, National Advanced School of Engineering, University of Maroua, Maroua, Cameroon.

10.22126/arww.2023.8723.1280

Abstract

This paper assesses the environmental impact of the wastewater treatment plant (WWTP) of the Cameroon Real Estate Company (CRE) camp in the "Cité-Verte" district in Yaoundé (Cameroon) and the causes of its malfunction. The study was carried out in two stages. The first stage consisted of describing the wastewater treatment steps of the WWTP, and analyzing the staff interviews in order to determine the causes of malfunction that had been suspected. The second phase consisted of collecting water samples at the entry of the WWTP (P1), inside the WWTP (P2), and at the outlet of the WWTP (P3). This, in order to produce a list of the WWTP's collecting systems, characterize the various types of wastewater (P1 and P2) and the treated wastewater (P3), and then determine the effect of effluent discharges on the environment. Finally, the structural and operational malfunctions of WWTP are identified using the Ishikawa and the Pareto diagrams. The results of water characterization show that the mean values of pH (7.7), EC (1059.3 μS/cm), TDS (524.6 mg/L), T° (23.6 °C), BOD5 (10.8 mg/LO2), NO3- (2.3 mg/L), and fecal coliforms (447.3 CFU/100 mL) are below the acceptable limit values of the Cameroonian standard of treated wastewater discharge. However, the mean values of TSS (269.3 mg/L), PO4
3- (1661.6 mg/L), K+ (1220.6 mg/L) and Escherichia coli (10133.3 CFU/100 mL) exceed the recommended values set by the Cameroonian standard of treated wastewater discharge. The values of the wastewater parameters at the sampling point P3 are globally lower than those at the sampling point P1 but higher than Cameroon’s standard for PO4
3- and K+. These results demonstrated that the current system (filters and plants) is appropriate but not optimal. The Pareto diagram reveals that the inadequate plant controls, unfavorable working conditions, lack of maintenance and
systematic control, and outdated equipment represent 20% of the causes responsible for 80% of the WWTP's malfunction. Therefore, the implementation of corrective and preventive measures is essential for better monitoring and determinization of the optimal performance of the WWTP of the CRE camp in the "Cité-Verte".

Keywords

Al-Dosary, M.M.S., Galal. and Abdel-Halim, H. (2015) ‘Environmental Impact Assessment of Wastewater Treatment Plants - (Zenien and 6th of October WWTP)’ International Journal of Current Microbiology and Applied Sciences, 4(1), pp. 953–964. Available at: https://www.ijcmas.com/vol-4-1/S.Al-Dosary,%20et%20al.pdf (Accessed: 7 December 2021).
APHA. (1995). Standard Methods for the Examination of Water and Wastewater, nineteenth ed. American Public Health Association, Washington DC, USA. Available at: https://www.wateronline.com/doc/standard-methods-19th-edition-is-now-availabl-0002  (Accessed: 7 January 2020).
Ayo, A. (2012) Evaluation des performances épuratoires de la station rénovée d’épuration des eaux usées du Camp Sic Messa. MA Dissertation. University of Yaoundé 1.
Baumont, S. et al. (2004) Réutilisation des eaux usées épurées : risques sanitaires et faisabilité en Ile-de-France. Observatoire régional de santé d’Ile-de-France, Institut d’aménagement et d’urbanisme de la région Ile-de-France, France. Available at https://www.ors-idf.org/fileadmin/DataStorageKit/ORS/Etudes/2004/Etude2004_2/REURapport_1_.pdf (Accessed: 12 March 2021).
Bonetta, S. et al. (2022) ‘Impact of wastewater treatment plants on microbiological contamination for evaluating the risks of wastewater reuse’ Environmental Sciences Europe, 34:20, pp. 1-13. doi: https://doi.org/10.1186/s12302-022-00597-0
‌Zhao, C. et al. (2015). International Conference on Education, Management and Computing Technology, Tianjin,13-14 June 2015. doi: https://doi.org/10.2991/icemct-15.2015.341
Goetsch, D.L. and Davis, S.B. (2003) Introduction to Total Quality: Quality Management for Production, Processing, and Services. 4th Edn. New Jersy: Prentice Hall.
Jaskulak, M. et al. (2022) ‘The Effects of Wastewater Treatment Plant Failure on the Gulf of Gdansk (Southern Baltic Sea)’ International Journal of Environmental Research and Public Health, 19, 2048, pp. 1-18. doi: https://doi.org/10.3390/ijerph19042048.
 
Law No. 96/12 of August 5, 1996. on the framework law relating to environmental management. Available at: https://minepded.gov.cm/wp-content/uploads/2020/01/LAW-NO.-9612-OF-05-AUGUST-1996-RELATING-TO-ENVIRONMENTAL-MANAGEMENT.pdf (Accessed: 17 January 2018).
Mohammad A. A. et al. (2015) ‘Environmental Assessment of Al-Hilla City Wastewater Treatment Plants’ Journal of Civil Engineering and Architecture, 9, pp 749-755. doi: https://doi.org/10.17265/1934-7359/2015.06.013
Prato, J.G. et al. (2022) ‘Adsorption of Phosphate and Nitrate Ions on Oxidic Substrates Prepared with a Variable-Charge Lithological Material’ Water, 14, 2454, pp. 1-18. doi: https://doi.org/10.3390/w14162454
Sighomnou, D. (2004) Analyse et redéfinition des régimes climatiques et hydrologiques du Cameroun : Perspectives d’évolution des ressources en eau. PhD Thesis. Université de Yaoundé 1. Available at:  http://www.documentation.ird.fr/hor/fdi:010063375 (Accessed: 11 November 2021).
Wethe, J., Radoux, M. and Tanawa, E. (2003) ‘Assainissement des eaux usées et risque socio sanitaire et environnementaux en zone d’habitat planifié de Yaoundé Cameroun’ VertigO, 4(1), pp. 1-12. doi: https://doi.org/10.4000/vertigo.4741
WWC (2000). The Hague 2000 | World Water Council. Available at:  https://www.worldwatercouncil.org/en/hague-2000 (Accessed: 23 January 2022).