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Application of GIS in Mine Contamination and Associated Environmental Impacts
Chade Salame and Arsalan SyedEAS 351: Environmental Application of GISDecember 6, 2016
Introduction to mining and acid mine drainage
GIS and Remote Sensing methods to measure mining impacts
Two case studies and limitations of GIS applications
Concluding remarks
Outline
Contamination Through Mining and AMD Mining has been a huge part of how we function day to day. It provides us with
minerals and elements and eventually, products that we use daily.
However, it comes at an expense when considering the environmental impacts and contamination that results from its activity. Degradation of the land, destruction of forestry, and contamination of surround soil
and groundwater.
One of the largest sites of contamination is a result of Acid Mine Drainage (AMD). It is the accumulation of acidic products in the environment from the process of mining. During exploitation, mines release metal sulphides (i.e. FeS2) that will oxidize by
reacting with water/atmosphere, then formation of sulfuric acid (H2SO4; Mounia et al., 2013).
4FeS2 + 15O2 + 14H2O => 4Fe(OH)3 ¯+ 8H2SO4
Figure 1: From the Tulsequah Chief Mine in northwestern British Columbia. Acid-leaching site into the Taku River that flows into Alaska (Tucker, 2016). Photo retrieved from https://goo.gl/gfFWpA.
Figure 2: Contaminated Colorado River. Accidental waste water seepage from the Gold King Mine. Highly acidic with heavy metals like iron, zinc, aluminum, copper, and cadmium. Retrieved from
https://goo.gl/1KGMfG.
General Methods The goal is to determine the spatial extent and level of pollution at
mining sites in order to develop or implement the best approach and technique in prevention and reclamation.
Must identify contaminant transport pathways and their locations (whether it be dump sites, excavation areas, etc).
Conventional methods of achieving this is by ground sampling and setting up systemic grids to cover large portions of land which can be time consuming and costly.
To address this issue, GIS and Remote Sensing can be used to develop flow pathway maps as a result of surface runoff.
Methods of Data CollectionLow Resolution Data:
MODIS AVHRR MERIS
Higher resolution data: Landsat Aster Ikonos Quickbird
These high resolution satellites can be used for geological mapping, subsidence related features, detailed pollution studies, and mining related infrastructure.
Radar data: Envisat ASAR TerraSar-X and TandDEM-X
Düzgün et al., 2011
Case Studies
Figure 3: Location of study area. Retrieved from Yenilmez et al. (2011).
Methods for Generating a Raster DEM and Flow Accumulation Map
Obtain topographic map
and an ASTER satellite image
ArcGIS 9.3 to generate DEM with 3D and
Spatial Analyst tools
Elevation contour map in Vector
format
DEM using TIN then to Raster DEM (Fig. 4)
Flow directions generated
Flow accumulation map
(Fig. 5)
36 soil samples collected
Elemental characterization of nearby coal to
determine contents
Analysis of results
Figure 4: Digital Elevation Model generated. High elevations are seen in white. Retrieved from
Yenilmez et al. (2011).
Figure 5: Flow accumulation map. High accumulation is represented by deeper colors.
Retrieved from Yenilmez et al. (2011).
Figure 6: Soil pH distribution with high elevation in grey. From Yenilmez et al. (2011).
Results
Figure 7: Distribution of Cr soil concentration. From Yenilmez et al. (2011).
Limit of Cr concentration is 100 mg/kg by the SPCR.
Results indicated a range of 195 to 650 mg/kg.
Significant amount of Cr contamination observed in the area and on flow pathways.
Trend was observed in almost all of the trace element studies.
Implications and Limitations of this Study Concentrations were higher (especially Cr, Ni, and Cu) closer to
contamination sources. Lower concentrations at higher elevations but higher concentrations downslope and along flow pathways.
Therefore, with the aid of GIS, we can locate areas that have a higher potential of being impacted by contamination via transport routes. Also, this would help determine sample locations, taking both less time and cost to do so.
However, more data is needed to supply background concentrations and what these values were beforehand to grasp a greater understanding of the area.
Study limited due to budget concerns.
They used the elemental characteristics of a coal seam from the Ilgaz-Ilisilik mining site so its not a true representation of the mining site of focus in this study.
Figure 8: Map of study area. Modified from Brugge et al. (2009).
Methods to Develop Risk Communication Strategy
Water Hauling Map
Collection of Survey and Participant
Demographics
Creation of Demographic
Tables
Water Sample Collection from
Wells
Relate Collected Water Sample
Data with Survey Data
ArcMap 9.2 Used to Create Base
Map Layers1m Resolution
RGB Orthophotos
Compilation of Chapter
Boundaries, Locations, Roads,
Mines, Hydrography
Water Hauling Map
Methods to Develop Risk Communication Strategy
Soil Restriction Map
Collection of Survey and Participant
Demographics
Creation of Demographic
TablesCollection of Soil
SamplesRelate Collected Soil Sample Data with Survey Data
Extrapolation of Soil Uranium
Concentration in Missing Data
Coverage Areas
Kriging Analysis to Create Sediment
Uranium Estimation
Apply Geostatistical Analyst Tool
Log Transformation of Data
Data Fit using Gaussian Semi-
Variogram
Manual Classification of
Uranium Concentration
Areas
Soil Restriction Map
Results
Figure 9: Percent of participants hauling water from unregulated source, regulated source and groceries. Modified from Brugge et al. (2009).
Figure 10: Recommended Water Hauling Map. Modified from Brugge et al. (2009).
Figure 11: Recommended Soil Restriction Map. Modified from Brugge et al. (2009).
Implications and Limitations of Study The presented water recommendation map was understood by the
Navajo tribe and they were able to identify regulated water wells in their area.
The soil restriction map was understood by the majority of the tribe with the exception of the elders.
The limitations include language barriers, available data to create additional features, and knowledge gap within the Navajo tribe.
Overall, the use of GIS based thematic mapping for risk communication was effective because it provides a new approach to risk based mapping which involves the community in the decision making process.
Conclusion
Application of remote sensing and GIS have a wide range of capabilities and can assist in developing maps that determine areas of contamination and can provide a low-cost alternative to remediation.
As explained in the two case studies, using GIS can give us an idea of the level of contamination in surrounding areas and allows us to focus on areas of immediate concern to address human impacts as well as, ecological and socio-cultural problems.
References Cited
Brugge, D., Cajero, M., Downs, M., Durant, J. L., George, C. M., Henio-Adeky, S., ... & Shuey, C. (2009). Development of risk maps to minimize uranium exposures in the Navajo Churchrock mining district. Environmental Health, 8(1), 1.
Düzgün, Ş., Künzer, C., & Karacan, C. Ö. (2011). Applications of remote sensing and GIS for monitoring of coal fires, mine subsidence, environmental impacts of coal-mine closure and reclamation. International Journal of Coal Geology, 86(1), 1-2.
Mounia, B., Mostapha, B., Rachid, H., Hassan, B., Abdelhakim, J., & Mohamed, S. (2013). Impact of mining wastes on groundwater quality in the province Jerada (eastern Morocco). International Journal of Engineering Science and Technology, 5(8), 1601.
Tukker, P. (2016). Owners of B.C.'s Tulsequah Chief mine site pushed into receivership. Retrieved December 05, 2016, from http://www.cbc.ca/news/canada/north/tulsequah-chief-mine-bankrupt-receivership-1.3758668
Yenilmez, F., Kuter, N., Emil, M. K., & Aksoy, A. (2011). Evaluation of pollution levels at an abandoned coal mine site in Turkey with the aid of GIS. International journal of coal geology, 86(1), 12-19.
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