RESPONSIBLE ENVIRONMENTAL STEWARDSHIP CONTINUED
and this includes water management and
related risks. The environmental perspective
considers, dust, rehabilitation, seepage and
other runoff issues.
Water management
As a scarce and shared resource, water
management is a key performance area for
the company. Water import sources include
utility companies, rivers and lakes, ground
water, and water draining into pits and deep
underground workings.
Variances between water consumption
(imports) at company operations is in uenced
by differences in climate, the nature of
available water sources, as well as mine and
processing plant designs. Over the past few
years, the company has consistently focused
on reducing the absolute amount of water
imported, as well as the intensity of water
utilisation as measured by kilolitres of water
used per tonne treated.
During the year, asset reduction in South Africa
had an impact on both absolute water imports
and water intensity. Water imports in South
Africa reduced by 28% and intensity reduced
by 20%. This resulted in an improved company
performance across both parameters. Work
will continue at all retained operations for
further improvements.
In South Africa, excess ssure water from
the operations of Blyvooruitzicht Gold Mining
Company Limited (in provisional liquidation) in
the West Wits remains a threat to Mponeng
Mine maintaining process water balance
and its ability to absorb large rainfall events.
The Blyvooruitzicht operations have been
purchased by Blyvoor Gold (Pty) Limited.
Through the year, Covalent Water Company (a
wholly owned subsidiary of AngloGold Ashanti)
pumped and discharged approximately
20Ml/day of extraneous water from
Blyvooruitzicht shafts, while the West Wits
operations absorbed around 5Ml/day of acidic
water from Blyvooruitzicht Mine 5 Shaft. To
eliminate the risk, Covalent Water Company
began evaluating options to intercept
and process the acidic water. Covalent
Water Company owns and operates the
Blyvooruitzicht 4 and 6 shafts in terms of a
registered servitude.
The containment and management of low
pH water seepage from waste rock facilities
at Iduapriem mine in Continental Africa also
required attention during the year. Remedial
actions included the commissioning of an
automated plant to actively treat low pH
seepage water from the base of the Block 1
waste rock facility at Iduapriem mine.
The Sansu community in the vicinity of
Obuasi mine has historically complained
of the mine contaminating ground water
resources. Two sets of consultants – the
Council for Scienti c and Industrial Research
and Envaserv Research – were commissioned
to independently test the ground water
and investigate the allegations of mine
pollution. The consultants representing the
community and mine respectively, concluded
assessments in the second half of the year.
The ndings of both studies were consistent,
demonstrating no evidence of mine pollution
of the ground water. Abnormalities detected
were related to natural geological factors.
The process to engage communities on the
findings commenced at the end of the year,
and Obuasi mine will offer guidance to
the community in responding to its water
quality challenges.
At Cuiabá mine in Brazil, access to surface
water was secured for the life of the asset
with receipt of an updated water use license
from the state environmental agency.
Additionally, a water use permit for the
AngloGold Ashanti owned hydro-electric
facility, Rio de Peixe, was renewed.
Cerro Vanguardia mine in Argentina has
faced the challenge of its water consumption
exceeding the annual abstraction allocation
which was set during a different phase of
operation. During 2018, the mine has engaged
directly with the Santa Cruz Province’s Water
Resources Directorate to secure approval for an
increased allocation.
At Tropicana gold mine in Australia, the rising
level of hypersaline groundwater at the tailings
storage facility has presented a challenge,
despite monitoring bores showing a localised
decline after water recovery pumping was
introduced. Additional water recovery bores
were commissioned to the south of the facility,
and pumping capacity has been augmented
to the west of the facility. By year end, it was
evident that the groundwater levels were
responding positively to the active pumping.
No detrimental impact to the environment has
been observed.
At a global level, AngloGold Ashanti played
an active role in the development of the
ICMM water stewardship position statement
and subsequent implementation guidance
document. As a participant in its design,
AngloGold Ashanti also presented an overview
of the position statement at a Future Water
Institute, of the University of Cape Town,
thought leadership meeting in August 2018.
Energy and climate change
In 2008, AngloGold Ashanti announced a
long-term target of reducing its greenhouse
gas (GHG) emission intensity by 30 percent
from 2007 levels. The time-frame was later
con rmed as 15 years (2022) and the metric
as tonnes of CO
2
equivalent per tonne of
ore treated. While improvements have been
made over the past 10 years, the closure
of underground South African assets in
early 2018, provided a step change in the
company’s emission intensity pro le, dropping
it to ~46% below the 2007 base year. Energy
ef ciency gains in the South Africa region
contributed much of the reductions achieved.
This included projects for which the South
African region has been publicly recognised.
SUSTAINABLE DEVELOPMENT REPORT 2018
49
SECTION 4 / MATERIAL ISSUES