Changes in surface water quality from small-scale gold mining operations in the Surinamean rainforest

Artisanal and small scale gold mining (ASGM) is an informal economic activity. ASGM is the process of extracting gold ore from the ground in the absence of land rights, mining license, exploration or mining mineral exploration permit or any legitimate document that allows the operation. Its haphazard nature, location close to and dependence on water have negative effects on the physical, chemical and biological composition of water. The socio-economic benefits of small scale mining, which include employment and income generation, are seriously outweighed by devastating environmental costs and impacts. The objective of this chapter is to examine effects of ASGM on water quality in Mozambique and Zimbabwe. Findings show that ASGM causes land disturbance, loss of biodiversity, deforestation and depletion of water resources, increased levels of siltation, turbidity and heavy metal content and the disturbance of aquatic life and its habitats. ASGM also negatively effects the health of people and animals. Based on the research findings, it is important to support and formalize, as much as possible, the mining operations so that it becomes environmentally friendly and sustainable.

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Fourier and Wavelet Analysis of Water Quality Signals

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.765-767.2848 ◽

2013 ◽

Vol 765-767 ◽

pp. 2848-2852

Author(s):

Wei Zhang ◽

Hong Li ◽

Dan Feng Sun ◽

Lian Di Zhou

Keyword(s):

Water Quality ◽

Surface Water ◽

Wavelet Analysis ◽

Temporal Pattern ◽

Surface Water Quality ◽

Small Scale ◽

Analysis Method ◽

Periodic Patterns ◽

Quality Signals ◽

Detailed Method

Taking the nitrogen monitoring data of two sites S1 and S2 in the period 1988-2003 in Baihe River lying Miyun reservoir stream watershed as a case, Fourier and Wavelet analysis were adopted to explore and compare the periodic patterns and temporal pattern characteristics of the two sites. The results showed that the periodic patterns of two sites were discovered using Fourier analysis. The site S1 had a period of two years, while the site S2 had no significant periodic patterns. The temporal pattern characteristics at different scales were obtained through wavelet analysis, which were at small scale for the site S1, while at moderate and small scales for the site S2. The Fourier and wavelet analysis method can both be used in the study of surface water quality temporal change pattern, the first is a coarse method and the latter is a more detailed method for analyzing surface water quality temporal pattern characteristics.

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Assessment of Surface Water Quality of Bétaré-Oya Gold Mining Area (East-Cameroon)

Journal of Water Resource and Protection ◽

10.4236/jwarp.2017.98064 ◽

2017 ◽

Vol 09 (08) ◽

pp. 960-984 ◽

Cited By ~ 6

Author(s):

Felaniaina Rakotondrabe ◽

Jules Remy Ndam Ngoupayou ◽

Zakari Mfonka ◽

Eddy Harilala Rasolomanana ◽

Alexis Jacob Nyangono Abolo ◽

...

Keyword(s):

Water Quality ◽

Surface Water ◽

Gold Mining ◽

Surface Water Quality ◽

Mining Area

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The impact of artisanal gold mining, ore processing and mineralization on water quality in Marmato, Colombia

Environmental Geochemistry and Health ◽

10.1007/s10653-021-00898-y ◽

2021 ◽

Author(s):

Keith W. Torrance ◽

Stewart D. Redwood ◽

Alessandro Cecchi

Keyword(s):

Water Quality ◽

Surface Water ◽

Gold Mining ◽

World Health ◽

Geochemical Data ◽

Small Scale ◽

Artisanal Mining ◽

Artisanal Gold Mining ◽

Ore Processing ◽

The Impact

AbstractMarmato, Colombia, has been an important centre of gold mining since before the first Spanish colonizers arrived in 1536. The Marmato deposit is hosted in a dacite and andesite porphyry stock as sheeted sulphide-rich veinlet systems. The district is currently experiencing a surge in both major mining projects and artisanal mining, driven by sustained high gold prices. Ore from small-scale and artisanal gold mining is processed in numerous small mills (entables) around Marmato, which impact surface water quality through the discharge of milled waste rock slurry, highly alkaline cyanide-treated effluent, and high dissolved metal loads. To investigate the impact of artisanal mining and ore processing, water samples were collected in January 2012 from streams around Marmato. The average dissolved metal concentrations in impacted streams were Zn, 78 mg L−1; Pb, 0.43 mg L−1; Cu, 403 µg L−1 Cd, 255 µg L−1; As, 235 µg L−1; Ni, 67 µg L−1; Co, 55 µg L−1; Sb, 7 µg L−1; and Hg, 42 ng L−1, exceeding World Health Organization drinking water guidelines. In addition, arsenic speciation was conducted in-situ and indicated that 91–95% of inorganic arsenic species is in the form of As(V). Spatial analysis of the data suggests that entables processing ore for artisanal miners are the main contributor to water pollution, with high sediment loads, alkalinity and elevated concentrations of dissolved arsenic, cadmium, mercury and lead, caused by the processing of gold-bearing sulphides in the entables. Geochemical data from surface water were compared to a comprehensive data set of whole rock analyses from drill core and channel samples from the deposit, indicating that the deposit is significantly enriched in gold, silver, lead, zinc, arsenic, antimony, and cadmium compared to crustal averages, which is reflected in the surface water geochemistry. However, elevated mercury levels in surface water cannot be explained by enrichment of mercury in the deposit and strongly suggest that mercury is being added to concentrates during ore processing to amalgamate fine gold.

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