A new study from the Andrew Lees Trust, which manages social and environmental projects in Madagascar, indicated that Rio Tinto subsidiary QIT Madagascar Minerals SA's Mandena operation polluted local water sources with radioactive substances, Mining Technology reported Sept. 5.
The Mandena ilmenite deposit forms part of the QMM property in southern Madagascar and is 80% owned by Rio Tinto, with the remainder held by the government. Ilmenite mining produces byproducts such as zircon and monazite, which both contain radionuclides such as uranium-238 and thorium-232.
Under Malagasy law, an 80-meter buffer zone must be maintained around environmentally harmful activities such as mining. QIT Madagascar claimed it was unaware of the law until 2013, four years after it finished building the mine.
As a result, the subsidiary secured a compromise from the government to reduce the buffer zone to 50 meters in exchange for building a dam between the Mandena project and the buffer zone. However, the Madena operation is just 24 meters from water bodies, according to the report.
The report also revealed that two nearby lakes were 4.6 meters above sea level, while the company had reported they were 0.6 meter above sea level, putting the lakes at high risk of being polluted by the waste from the mining operation.
Steven Emerman, the author of the report, established that the proximity of the mine to the lakes represented a serious risk to public safety as the lakes are an important source of water and food for locals.
In response, Rio Tinto said QIT Madagascar was operating within the law, and it is trying to schedule a discussion with the Andrew Lees Trust.