However, the effects of former mining activities are numerous in their impact on the
environment of the region. At this place it should also be noted that ‘closed’ or
‘abandoned’ mine status does not necessarily imply that the problems are less than
those experienced in active mining areas, since the environmental standards were
considerably lower in the past and the competence of the authorities could have been
rather limited (Puura and D’Alessandro 2005). One of the most critical areas is
Šobov, situated 3 km northeast of Banská Štiavnica city. It is an open mine where
hydrothermal quartzite was extracted and then transported, crushed and grinded at a
nearby plant in Banská Belá for refractory bricks. The mined ore often contained
pyrite and clay minerals, mainly illite and pyrophyllite (Uhlík and Šucha 1997)
which were left on site as waste and had been accumulated along over 30 years
(Šottník et al. 2002). In the course of time, pyrite deposited on the pile in large
amounts has been under the slow attack of weathering processes and oxidized,
forming sulfuric acid. The acid attacks other minerals and accelerates migration of
different toxic elements (Kubová et al. 2004, 2005; Bujdoš et al. 2005). The water
that flows out from the mine site represents typical acid mine drainage with high
metal concentrations and pH as low as 1.2–2.5. The major dissolved components are
Al, Fe and SO 4
2À , followed by Zn, Mn, Cu, Pb and As (Matúš 2007; Matúš and
Kubová 2005, 2006, 2008; Matúš et al. 2003, 2004, 2005, 2006). The dissolved salt
concentrations remain between 15 and 50 g L
À1 (Šucha et al. 1997; Šottník et al.
2002). The acid mine drainage is associated with enormous damage to the entire
surrounding habitat, it causes significant changes in soil properties and plant species
richness. In the last decades, different remediation strategies have been implemented
to reduce negative influence of these waters, but with little success. In 1999, a
passive treatment system was designed to treat acid mine drainage, with aerobic
terrace with wetland vegetation arranged in the last stage (Šottník and Šucha 2001).
In order to at least partially prevent the negative effect of acid mine drainage, a
simple construction – the surface channel system – has been built to collect acid
water that flows out of the dumps into an open pool from which it is subsequently
delivered by an underground tube into the deep abandoned mine (Lintnerová 2002).
The polluted area covers an estimated 145,000 m
2 , badlands with no vegetation or
humus cover spread for 35,000 m
2 (Dlapa et al. 2002; Šottník et al. 2002; Medveď
et al. 2004, 2006, 2008).
The second sampling site was situated in Pezinok region (Little Carpathian Mts.),
in so-called Pezinok-Pernek crystalline complex, known for its ore deposits. The
sample was taken from the soil at a Sb ore dump site situated on the south-eastern
side of the mountain above the town. This area has several thousand years of history
in ore mining. With a series of little breaks, it was mined for antimony until the early
1990s, when an interest in antimony had dropped off due to the end of the Cold War;
besides that, only residual deposits of Sb remained on the site. The ore mining and
dressing have significantly contributed to Sb and As contamination of soils,
sediments and waters (Čerňanský et al. 2007, 2009; Urík et al. 2007; Kubová et al.
2008a, b; Kališ and Matúš 2011; Littera 2011). Nowadays, a surface water leaking
out of the mining dump has a pH of 4–6.5, and although it is partially purified by a
natural process of mechanical sedimentation and sorption in the sludge pond, the
5 The Recent Strategies Employed in Chemical Analysis of Contaminated Waters,. . .
157
environment of the region. At this place it should also be noted that ‘closed’ or
‘abandoned’ mine status does not necessarily imply that the problems are less than
those experienced in active mining areas, since the environmental standards were
considerably lower in the past and the competence of the authorities could have been
rather limited (Puura and D’Alessandro 2005). One of the most critical areas is
Šobov, situated 3 km northeast of Banská Štiavnica city. It is an open mine where
hydrothermal quartzite was extracted and then transported, crushed and grinded at a
nearby plant in Banská Belá for refractory bricks. The mined ore often contained
pyrite and clay minerals, mainly illite and pyrophyllite (Uhlík and Šucha 1997)
which were left on site as waste and had been accumulated along over 30 years
(Šottník et al. 2002). In the course of time, pyrite deposited on the pile in large
amounts has been under the slow attack of weathering processes and oxidized,
forming sulfuric acid. The acid attacks other minerals and accelerates migration of
different toxic elements (Kubová et al. 2004, 2005; Bujdoš et al. 2005). The water
that flows out from the mine site represents typical acid mine drainage with high
metal concentrations and pH as low as 1.2–2.5. The major dissolved components are
Al, Fe and SO 4
2À , followed by Zn, Mn, Cu, Pb and As (Matúš 2007; Matúš and
Kubová 2005, 2006, 2008; Matúš et al. 2003, 2004, 2005, 2006). The dissolved salt
concentrations remain between 15 and 50 g L
À1 (Šucha et al. 1997; Šottník et al.
2002). The acid mine drainage is associated with enormous damage to the entire
surrounding habitat, it causes significant changes in soil properties and plant species
richness. In the last decades, different remediation strategies have been implemented
to reduce negative influence of these waters, but with little success. In 1999, a
passive treatment system was designed to treat acid mine drainage, with aerobic
terrace with wetland vegetation arranged in the last stage (Šottník and Šucha 2001).
In order to at least partially prevent the negative effect of acid mine drainage, a
simple construction – the surface channel system – has been built to collect acid
water that flows out of the dumps into an open pool from which it is subsequently
delivered by an underground tube into the deep abandoned mine (Lintnerová 2002).
The polluted area covers an estimated 145,000 m
2 , badlands with no vegetation or
humus cover spread for 35,000 m
2 (Dlapa et al. 2002; Šottník et al. 2002; Medveď
et al. 2004, 2006, 2008).
The second sampling site was situated in Pezinok region (Little Carpathian Mts.),
in so-called Pezinok-Pernek crystalline complex, known for its ore deposits. The
sample was taken from the soil at a Sb ore dump site situated on the south-eastern
side of the mountain above the town. This area has several thousand years of history
in ore mining. With a series of little breaks, it was mined for antimony until the early
1990s, when an interest in antimony had dropped off due to the end of the Cold War;
besides that, only residual deposits of Sb remained on the site. The ore mining and
dressing have significantly contributed to Sb and As contamination of soils,
sediments and waters (Čerňanský et al. 2007, 2009; Urík et al. 2007; Kubová et al.
2008a, b; Kališ and Matúš 2011; Littera 2011). Nowadays, a surface water leaking
out of the mining dump has a pH of 4–6.5, and although it is partially purified by a
natural process of mechanical sedimentation and sorption in the sludge pond, the
5 The Recent Strategies Employed in Chemical Analysis of Contaminated Waters,. . .
157