Perilous Times
Rising tide of toxic acid mine water threatens Johannesburg
A toxic tide of acid mine water is rising steadily beneath Johannesburg
which, if left unchecked, could cause earth tremors, power blackouts
and even cancer among residents, experts have warned.
By Aislinn Laing, Johannesburg
Published: 5:19PM BST 06 Sep 2010
Particularly at risk is the central business district which is built
over the central basin and is home to some of Africa?s biggest firms
Photo: ALAMY
The water is currently around 600 metres below the city’s surface but
is rising at a rate of between 0.4 and 0.9 metres per day, meaning it
could overflow onto the streets in just under a year and a half.
Because it would take 13 months to build a pumping station to clear the
water, a legacy of 120 years of mining around Johannesburg, the state
has just four months to find the millions of pounds needed to fund it.
It is currently locked in negotiations with multinational mining firms
who have profited from the area’s rich natural resources over who
should pay and how much.
Announcing a task force of experts set up to deal with the issue
yesterday, Water and Environmental Affairs Minister Buyelwa Sonjica
said she was hoping that the potential dividends from tapping a new
water supply for human consumption and use in industry would entice
investors.
Acidic water is created when abandoned mine shafts and tunnels fill up
with ground water which oxidises with heavy metals and the sulphide
mineral iron pyrite, known as “fool’s gold” because of its yellowish
hue.
Without effective drainage, it pours out into waterways, polluting
crops and poisoning those living nearby.
According to water activist Mariette Liefferink, from the Federation
for a Sustainable Environment, the water is the same acidity of lemon
juice or vinegar and poses an “enormous threat” to the city and its
inhabitants.
Particularly at risk is the central business district which is built
over the central basin and is home to some of Africa’s biggest firms.
According to Miss Liefferink, the buildings they are housed would be
damaged as the mine water corrodes steel and concrete.
She added that some of the city’s poorer residents are already living
on top of mine dumps filled with carcinogenic metals which, if they
react with the rising mine water, will pollute the entire water system.
“This environmental problem is second [in South Africa] only to global
warming in terms of its impact, and poses a serious risk to the area as
a whole,” she told the water affairs portfolio committee.
Marius Keet, a senior government official in charge of water
management, said that when the rainy season arrives in the coming
months, the tide will begin rising faster and the results could be
“catastrophic”.
Mr Keet said the recommended “environmental critical level” for the
rising acid mine water was 150m below surface. The environmental
impacts should it rise above this level, he said, include earth tremors
and the possible formation of sinkholes.
Minister Sonjica has given her team of experts six weeks to find
investors and come up with a viable rescue package which she will then
take to the Cabinet for approval.
At present, the price tag of a new pump station and pipeline, and an
upgrade to an existing waterworks – all of which are deemed essential
for treating the acid mine water – is R218 million (£19m). However, the
current budget only allows for investment of R14 million.