Application of multivariate statistical analysis and a geographic information system to trace element contamination in the Chungnam Coal Mine area, Korea

In order to examine contamination in the Chungnam Coal Mine area, rock, stream sediment and water samples were collected and analyzed for trace elements. In order to compile the drainage-based geochemical maps, catchment basins were calculated using aspects of DEM (data elevation model) and stream-line segments. The constructed DEMs with 3 types of resolution were examined, these need to be properly used for well-shaped and accurate catchment basins. The stream-line segments and sampling points were also considered as a target image for watershed segments and it was found that the stream-line segments as target images were better role at reflecting the catchment area rather than the sampling points. It is important that the geochemical databases were manipulated to present the various phenomena. Factor analysis in R-mode was used to integrate geochemical data, and the input data for factor analysis were the concentrations of 12 trace elements in stream sediment and 3 anion concentrations and pH values in stream water. Using a maximum likelihood scheme, eigenvalues that explained about 90% of total variance were established and 4 factors were selected. Factors 1 and 2 indicated relative enrichment of trace elements, factor 3 was explained by human activities of residents and factor 4 was related to the pH of stream water. The drainage-based geochemical maps with 4 kinds of factor scores were compiled.