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Heavy metal contamination
in groundwater due to mining activities in Sukinda valley,
Orissa - A case study
Ratnakar Dhakate and V. S. Singh
National
Geophysical Research Institute, Uppal Road, Hyderabad – 500
007 (A.P.) India
*Corresponding author. E-mail:
dhakate_ratnakar@yahoo.com.
Tel: 040-23434700. Fax: 040-27171564.
Accepted
5 June, 2008 |
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Sukinda
Valley, Orissa is known for its chromite ore deposits. The
open cast mining for chromium is being carried out since
1950. The extraction of chromite has mostly been carried out
by open cast and at few places by under ground mining
methods. The possibility of leaching contaminants from the
ore material kept in the open ground or from the wastages or
degraded ore material produced during the mining processes
may contaminate the groundwater in the study area. There is
also a high possibility that the contaminants will move to
the aquifer system from the seepage of bottom floor of the
mining quarry. In order to assess the chemical quality,
groundwater samples from different part of the study area
for post and pre-monsoon period have been collected and
analyzed for various contaminants. This study showed that
the groundwater in the study area was nearly neutral to
mildly alkaline in pH (6.1 - 7.6) with low to moderate TDS
(50 - 507 mg/l). High TSS (4 - 64 mg/l) indicates the
influence of mine’s waste on the groundwater quality,
because the TSS particles remains as suspended colloidal
particles in groundwater and are hence toxic as far as the
groundwater potability is concerned. TSS levels are higher
than the normal permissible limits of potable water and
require a proper filtration process before human
consumption. Metallic trace elements such as Cu (0.01 - 1.8
mg/l) and Cr(VI) (0.01 to 0.45 mg/l) are more than the
permissible limits at some places in different seasons and
my cause health hazards. In general, good groundwater
conditions as well as simultaneous dissolution and dilution
restraint the chromite and other heavy metals in
groundwater.
Key
words:
Heavy metals, dissolution, dilution, ultramafic rocks. |
