Swakop Uranium yesterday gave an assurance that it has done all it could to minimise the environmental impact of a leak at its Husab tailings dam caused by a pump failure earlier this year.
Environmental watchdog Earthlife Namibia issued a statement yesterday in which it accused Swakop Uranium of downplaying the risks of the leak to the environment and human health.
The statement explained that the tailings dam is the most dangerous part of the entire process of a uranium mine as it contains 85% of the radiating material from the original uranium ore, and that the milling process only extracts uranium from the ore, while the decay products remain in the tailings.
Earthlife stated that the "decay chain", including radioactive substances such as thorium-230 and radium-226, was concerning, and that radium-226 was of specific concern as it continuously decays to radon-222, which escapes as a gas into the air. This can apparently cause lung cancer when inhaled.
Radon gas can also be carried far by winds. A part of it can also decay into other radioactive elements, possibly dropping onto soil, vegetation, and on surface water.
"It can permeate into groundwater, our scarcest and most precious resource, which can be contaminated in a way that it will never again be fit for consumption," the statement stressed.
Earthlife rejected Swakop Uranium's investigation report that the spill affected a small area inside the perimeter of the tailings storage facility fence, which is not accessible to the public or animals.
"Keeping in mind that radiation and contamination do not respect any borders, the statement trivialises the dimension of the hazard. This is unfortunately common practice by the management of big companies worldwide to silence the public after disasters happened," the watchdog said.
"The fact that the pumps have failed indicates inadequate maintenance of the equipment. How can it happen that a business of such huge and hazardous level is handled so irresponsibly? We cannot accept the gamble with our environment, and the health of its people. The short-term benefits for a few don't by any means justify the harmful social and environmental impacts," the letter added.
Swakop Uranium's vice president for human resources and business support, Percy McCallum, reiterated that the company did all it could to contain and fix the problem, and gave an assurance that there is no risk to the environment or people.
An investigation was done by the department of environmental affairs, the national radiation protection authority, the Ministry of Agriculture, Water and Forestry, and an external environmental consultancy. It revealed that the pumps at some of the lined seepage collection ponds partially failed, and with the continuous inflow of the seepage water, it resulted in the lined seepage ponds overflowing onto the unlined surroundings.
McCallum said when the external regulators examined the area, there were no longer any overflows of the seepage ponds as corrective action had already been taken to repair the pumps in time, and additional pumps were used to pump the water back into the tailings dam.
In addition to the water analysis done by the mine, the ministry also took independent samples for verification. The company continues to frequently monitor the tailings storage facility and surrounding boreholes, he added.
McCallum said rehabilitation was done to neutralise the sand patches where the spill occurred, and the subsequent rehabilitation of the areas started, and is continuing.
The executive director of the Namibian Uranium Institute, Gabi Schneider, said while Earthlife's "decay chain" was correct, the risk to the environment and humans was from small to non-existent.
"Namibian uranium ores are extremely low grade, and 85% of a low grade ore is therefore even less," Schneider explained. "Because of this low grade, the emission of radiation is also low."