Renewed concern has been expressed regarding uranium mining activities along the coastal areas and its impact on the environment following tests undertaken by the Commission for Independent Research and Information about Radiation (CRIIRAD) and EARTHLIFE Namibia.
These mining activities have a direct bearing on people’s health as they reportedly cause cancer, especially to people that get exposed to them.
According to CRIIRAD, people that spend 30 minutes to 35 hours at a distance below 25 meters from the waste rock dump, would receive an external radiation dose above the trivial dose of 10 microsieverts per year.
One of the main concerns is uranium concentrates found in underground water sources and on sediments in areas where RÃ¶ssing and the Langer Heinrich mines are found, especially along the Khan and Gawib rivers.
According to Bruno Chareyron, a Nuclear Physics Engineer and Director of the CRIIRAD Laboratory, the radioactive tailings (waste) of the mines are not covered and dust particles from the tailings are accumulating on bushes and slopes.
“When it rains, this dust is even washed off the waste rock dumps that are situated next to the river banks and therefore deposited into the river system,” the nuclear engineer said.
Chareyron said some waste rocks are dumped on the banks of the Khan River, at the intersection with Dome Gorge, without fencing and confinement.
“The radiological impact of this activity has to be studied in detail, but preliminary measurements show various impacts on the environment,” he said in a preliminary report.
Chareyron said the Nuclear Energy Council of South Africa (NECSA) that evaluated the radiological public hazard assessment for the Expansion of Rössing Uranium mine has not taken this impact into consideration.
In addition, preliminary monitoring of Radon gas activity in the immediate air near the rocks shows high readings.
The readings are 48 times above typical mean natural Radon activity in the open air.
According to Chareyron, the World Health Organisation (WHO) acknowledges that Radon, which is a heavy gaseous radioactive chemical, is the second cause of lung cancer after smoking.
Uranium, even when purified, Chareyron said is radioactive and miners cannot really be protected from it.
Chareyron was surprised to read in official Namibian documents that metal drums containing the yellow cake are effective barriers to the emanation of any radiation.
According to the engineer, he had measured a very high dose of radioactivity when he was passing a truck transporting yellow cake in France, especially as he was getting closer to the truck.
With regard to water contamination, Chareyron said the high uranium concentrate in underground water collected downstream Rössing Uranium mine in the Khan and Swakop rivers’ alluvium raises the question of the origin of that uranium.
What raises the suspicion is the fact that, in the Khan River upstream and in Swakop River upstream and the confluence with Gawib River, the 238 uranium concentrations are much lower.
The Langer Henirich mine is located in the riverbed of the Gawib River’. Chareyron said the Khan River alluvium immediately downstream of the Dome Gorge’s waste rock dump site, measured a uranium concentrate of 430.
“This may be due to the fact that a fraction of the uranium contained in the rocks is dissolved by rain water and eventually reaches the groundwater,” the nuclear engineer added.
Rössing has a network of “dewatering wells” and trenches designed to allow pumping back of the contaminated waters to the tailings dam.
However, Chareyron advised that the efficiency of this system and its durability in the future be studied to gain better understanding.
He also measured radiation on the parking area of the Rössing mine, which was six times above natural background value.
The Rössing Uranium mine has admitted that it uses tailings as road cover in the mines, in order to smoothen surfaces and enhance haul- truck tyre life.
The nuclear engineer, however conceded that the interpretation of all the results would require additional work.
Collected data will be compared later with monitoring results gathered by the mining companies and discussed at various meetings next week in Swakopmund with mining companies, local radiation experts, the Uranium Institute, locals and concerned non-governmental organisations.
Preliminary results have been brought to the attention of the National Radiation Protection Authority at a meeting in Windhoek with the Ministry of Health and Social Services. The assays where carried out between September and October 2011.
Scientists from the CRIIRAD laboratory took radiation measurements in situ, and collected 14 samples of top soil, 13 samples of surface sediments from the Swakop, Gawib and Khan rivers and 11 underground water samples in the alluvium of the Swakop and Khan rivers and tap water from Arandis.
Both the Rössing Uranium mine and Langer Heinrich, as well as the Uranium Institute confirmed receipt of the report and pledged to respond to it next week.