Physico-chemical Characteristics of Wastewater from a Ball Mill Facility
in Small-Scale Gold Mining Area
of Paracale, Camarines Norte, Philippines

Jessie O. Samaniego1,2,* and Maria Antonia N. Tanchuling2

1Department of Science and Technology - Philippine Nuclear Research Institute,
Commonwealth Ave., Quezon City, Philippines

2Environmental Engineering Graduate Program, College of Engineering,
University of the Philippines - Diliman, Quezon City, Philippines

*Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.



Small-scale gold miners in Paracale, Camarines Norte use amalgamation process to recover gold from mined ores. In the process, they dispose untreated wastewater to water bodies. In this study, wastewater from an active SSGM ball mill facility in the area was analyzed for physico-chemical parameters and heavy metal concentrations. A total of 40 samples were gathered from the ball mill facility while in full operation and were analyzed for heavy metals (As, Ba, Cd, Hg, Pb). Results showed that all metals (except for Ba) exceed the effluent regulatory limits including Hg (0.1768 mg/L) and Pb (9.3821 mg/L), which are 44 and 94 times higher than the limit, respectively. Presence of Hg concentration in the wastewater confirms the miners’ illegal use of Hg in amalgamation process. Based on the mercury balance in amalgamation, around 16.8% of total Hg input goes to the sediment and some 0.21% mixed with wastewater and the bulk 82.99% is in the form of amalgam that becomes Hg vapor after burning. Physico-chemical parameters – temperature, pH, and true color – are within their respective effluent regulatory limits for Class C waters, while TSS (3,596.9 mg/L) is 36 times higher than the 100 mg/L limit. Other parameters, though not regulated, such as ORP (343.9 mV), turbidity (> 800 NTU), and apparent color (9,880 PCU) were analyzed with high concentrations. From this study, wastewater treatment is recommended before disposing of to the receiving waters to reduce the concentration of heavy metals and TSS. Also, the full and strict implementation of the people’s small-scale mining law must be maintained to protect human health as well as the environment from the adverse effect of the use of Hg in SSGM processes. . . . . read more



Small-scale gold mining (SSGM) plays an important role in poverty alleviation in the rural communities, especially in the developing countries including the Philippines. It is a source of livelihood of at least 10-20 million people worldwide (Telmer & Veiga 2008), while the International Labor Organization (ILO) extrapolated that 80-100 million people worldwide are directly and indirectly dependent on this activity for their livelihood (Hinton et al. 2003; Hentschel et al. 2003). As the price of gold continues to rise, the SSGM activities around the world also continue to grow. In effect, the demand for mercury (Hg), which is being used in amalgamation process in many SSGM areas, is also increasing and currently it represents 1/3 of worldwide Hg consumptions (Telmer & Veiga 2008).



ACHEAMPONG MA, MEULEPAS RJW, LENS PNL. 2010. Removal of Heavy Metals and Cyanide From Gold Mine Wastewater. J Chem Technol Biotechnol 2010; 85: 590-613.
AKAGI H, CASTILLO ES, CORTES-MARAMBA N, FRANCISCO-RIVERA AT, TIMBANG TD. 2000. Health Assessment for Mercury Exposure Among Schoolchildren Residing Near a Gold Processing and Refining Plant in Apokon, Tagum, Davao del Norte, Philippines. The Science of the Total Environment 259: 31-43.
AL-GARNI SM, GHANEM KM, IBRAHIM AS. 2010. Biosorption of Mercury by Capsulated and Slime Layer-forming Gram-ve Bacilli From an Aqueous Solution. African Journal of Biotechnology 9(38): 6413-21.
 [APHA, AWWA, WEF] American Public Health Association, American Water Works Association, Water Environment Federation. 1998. Standard Methods for the Examination of Water and Wastewater, 20th. Ed., Washington DC, USA.
APPLETON JD, WILLIAMS TM, BREWARD N, APOSTOL A, MIGUEL J, MIRANDA C. 1999. Mercury Contamination Associated With Artisanal Gold Mining on the Island of Mindanao, the Philippines. The Science of the Total Environment 228: 95-100.
BHATNAGAR A, DEVI P. 2013. Water Quality Guidelines for the Management of Pond Fish Culture. International Journal of Environmental Sciences, Volume 3 No. 6, 2013.
CORPUS TJ, DAVID CP, MURAO S, MAGLAMBAYAN V. 2011. Small-scale Gold Mining in the Ambalanga Catchment, Philippines: Its Control on Mercury Methylation in Stream Sediments. International Journal of Environmental Sciences Volume 2, No. 2, 2011.
CORTES-MARAMBA N, REYES JP, FRANCISCO-RIVERA AT, AKAGI H, SUNIO R, PANGANIBAN LC. 2006. Health and Environmental Assessment of Mercury Exposure in a Gold Mining Community in Western Mindanao, Philippines. Journal of Environmental Management 81(2006): 126-134.
[DENR] DENR Administrative Order No. 2015-03. 2015. Revised Implementing Rules and Regulations of Republic Act No. 7076, Otherwise Known as “People’s Small-Scale Mining Act of 1991”. Republic of the Philippines, Department of Environment and Natural Resources. 25p.
[DENR] DENR Administrative Order No. 2016-08. 2016. Water Quality Guidelines and General Effluent Standards of 2016. Republic of the Philippines, Department of Environment and Natural Resources. 25p.
[DENR] DENR Administrative Order No. 34. 1992. Subject: Rules and Regulations to Implement Republic Act No. 7076 Otherwise Known as People’s Small Scale Mining Act of 1991. Republic of the Philippines, Department of Environment and Natural Resources. 16p.
DE BEER M, KRUEGER D, MAREE J, MBHELE N, PHALANNDWA M, NOVHE O. 2008. Limestone Neutralisation of Arsenic-rich Effluent from a Gold Mine. Mine Water and the Environment 27(1): 46-51.
DHARMAPPA HB, SIVAKUMAR M, SINGH RN. 1995. Wastewater Minimization and Reuse in Mining Industry in Illawara Region. Proceedings of IMWA 1995: Water Resources at Risk, 14-18 May 1995. Denver, American Institute of Hydrology. International Mine Water Association.
DIOLA MBL. Human Health Exposure and Risk Assessment of Environmental Mercury Contamination in Residential Areas of Camp 6, Tuba, Benguet. [MS Thesis]. Quezon City, Philippines. University of the Philippines - Diliman. (Available at College of Engineering Library II).
 [EMB-REGION 5] Environmental Management Bureau - Region 5. 2004. Mineral Resources by Province: Camarines Norte. Retrieved from on 11 Sep 2017.
[EMB-REGION 5] Environmental Management Bureau - Region 5. 2016. Minahang Bayan in the Bicol Region. Retrieved from on 10 Nov 2017.
GIESE U, KNITTEL U, KRAMM U. 1986. The Paracale Intrusion: Geologic Setting and Petrogenesis of a Trondhjemite Intrusion in the Philippine Island Arc. Journal of Southeast Asian Earth Sciences 1(4): 235-245.
HENTSCHEL T, HRUSCHKA F, PRIESTER M. 2003. Artisanal and Small-Scale Mining Challenges and Opportunities. International Institute for Environment and Development and World Business Council for Sustainable Development. London.
HINTON JJ, VEIGA MM, VEIGA ATC. 2003. Clean Artisanal Gold Mining: A Utopian Approach?. Journal of Cleaner Production 11: 99-115.
ISRAEL DC, ASIROT JP. 2002. Mercury Pollution Due to Small-Scale Gold Mining in the Philippines: An Economic Analysis. Philippine Institute for Development Studies. Research Paper Series No. 2002.02.
MAGLAMBAYAN VB, MURAO S, CORPUS TJC, SERA K, FUTATSUGAWA S, TSUJI M. 2005. Mercury Contamination Associated with Small-Scale Gold Mining in the Upper Ambalanga River, Benguet, Philippines from River Sediment Sampling. Conference Proceedings of Asia-Pacific Learning Event, 7-12 June 2005. Philippine Sustainable Development Network Foundation, Inc.
[MNR] Mines Administrative Order No. MRD-41. 1984. Rules and Regulations Governing the Granting of Small Scale Mining Permits under Presidential Decree No. 1899. Republic of the Philippines, Ministry of Natural Resources. 9p.
PEREZ E, APPEL PWU. 2007. Training of Small Scale Miners and their Families in Safe Handling of Mercury During Extraction of Gold in the Philippines. Improving Access to Social Services: health services and income opportunities for Small Scale Miners and Their Families. Danmarks Og Grønlands Geologiske Undersøgelse Rapport 2007/35. Geological Survey of Denmark and Greenland, Ministry of the Environment.
PIRRONE N, MASON R. 2009. Mercury Fate and Transport in the Global Atmosphere: Emissions, Measurements and Models. Springer Science+Business Media, LLC.
SAMANIEGO JO, TANCHULING MAN, RESURRECCION AC, GARCIA TP, ONG DC. 2013. Water and Sediment Quality of Small Scale Gold Mining Sites in Camarines Norte, Philippines. Proceedings of the International Conference on the Preservation and Rehabilitation of Urban Water Environment for Asian Core Program of NRCT, JSPS, and ERDT. Bangkok, Thailand. 23 Nov 2013.
SAMANIEGO JO, TANCHULING MAN, RESURRECCION AC, GARCIA TP, ONG DC, INOUE T, CHOULAMNY V. 2014. Mercury Pollution of Water and Sediment in Small Scale Gold Mining Area in Camarines Norte, Philippines. Proceedings of 7th ASEAN Environmental Engineering Conference, USB-WQ03, Puerto Princesa City, Philippines, 21-22 Nov 2014. ISBN 978-616-374-596-5.
SORIANO VJ. 2012. A Simplified Sustainable Manufacturing Paradigm for Small Scale Gold Production Systems. ASEAN Engineering Journal Part A, Vol. 2 No. 2, ISSN 2229-127X: 30-42.
TELMER H, VEIGA M. 2008. World Emissions of Mercury From Artisanal and Small Scale Gold Mining and the Knowledge Gaps About Them. In: Mercury Fate and Transport in the Global Atmosphere. UNEP Mercury Fate and Transport Partnership (in publication).
[TETRA TECH] Tetra Tech EM Inc. 2001. Semi-detailed Assessment of Abandoned Mines in the Philippines. 50p. Retrieved from on 16 Nov  2017.
UNIDO-GLOBAL MERCURY PROJECT. 2006. Manual for Training Artisanal and Small-Scale Gold Miners. UNIDO, Vienna International Center, D-12. Vienna, Austria. Retrieved from on 11 Sep 2017
VARGAS EP, RAMIREZ JD, TABORA EU, DIWA RR, PALATTAO BL, REYES RY. 2016. Cu-mo With Associated Uranium Mineralization Within Larap Mineralized Area, Camarines Norte, Philippines: A Revisit. Journal of East China University of Technology, Vol. 39, Suppl., Sep 2016.
VELASQUEZ-LOPEZ PC, VEIGA MM, HALL K. 2010. Mercury Balance in Amalgamation in Artisanal and Small-scale Gold Mining: Identifying Strategies for Reducing Environmental Pollution in Portovelo-Zaruma, Ecuador. Journal of Cleaner Production 18: 226-232.
VEIGA MM, MAXSON PA, HYLANDER LD. 2005. Origin and Consumption of Mercury in Small-scale Gold Mining. Journal of Cleaner Production 14: 436-447.
ZHU Y, AN F, TAN J. 2011. Geochemistry of Hydrothermal Gold Deposits: A Review. Geoscience Frontiers 2(3): 367-374.