parameters. If the correlation coefficient (r) is
greater than 0.7 and between 0.5 and 0.7, it
indicates strong and moderate correlation of two
parameters, respectively. Based on Spearman’s
correlation, it was found that the correlation
between EC (salinity) and TDS with the major
components of seawater (Na
+
, Mg
2+ , Cl
− , SO 4
2− )
showed significant positive correlation (TDS and
Mg
2+ (r = 0.774); TDS and Na
+
(r = 0.594);
TDS and Cl
− (r = 0.825) and TDS and SO 4
2−
(r = 0.602)) that reflects signs of seawater
influence on the groundwater salinity. The significant correlation of Cl
− ion with Na
+ and Mg
2+
(Cl
−
and Na
+
(r = 0.659); Cl
−
and Mg
2+
(r = 0.872)) reflects the significance of seawater
intrusion into groundwater in the active mining
area. The main contributors to the groundwater
salinity are Na
+
, Mg
2+ , Cl
− and SO 4
2− , which
show significant correlation with EC similar to
TDS.
14.1.3.4 Mechanism Controlling
the Groundwater
Chemistry (Gibbs Plot)
Gibbs (1970) established the mechanism controlling the chemical composition of groundwater
to find out a close relationship between chemical
composition of water and aquifer lithological
Fig. 14.4 Spatial distribution
map of chloride
14 Impacts of Beach Placer Mineral Mining …
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