Namibian Marine Phosphate (NMP), a Namibian based marine phosphate mining company that will be developing Sandpiper Project, located off the Walvis Bay coast, has made a firm commitment that its mining activities will be subjected to the highest standards of environmental monitoring. This monitoring will be conducted in accordance with the activity programme recommended by independent environmental specialists, which recommendations forms an integral part of NMP’s final Environmental Management Plan (EMP).
NMP Project General Manager David Wellbeloved says the company considers the environment as one of the key priorities and takes its responsibilities and the public concerns seriously.
“Environmental impact assessment studies have shown that the recovery of phosphate sediment in the mining area (ML170) can be undertaken with relatively low impact to the seawater quality. Furthermore, NMP will comply with all Namibian environmental regulations and best practices,” he says. “We will be implementing a monitoring programme, in line with the expert’s recommendations as incorporated in the final EMP, to ensure that our impact is measured, monitored and minimised.”
The quality of seawater within ecosystems is important as it affects the marine life which has evolved to fill specific ecological niches.
Based on their specialist studies, the independent experts have concluded that the anticipated dredging activities lie seaward of the mud belt which is generally associated with high hydrogen sulphide concentrations and would have a limited impact on water quality and organisms living on the seabed.
NMP’s plans to dredge phosphate enriched marine sediments from the seabed at depths of between 200 and 275 metres off Namibia’s continental shelf, which would entail the removal of the sediment into the dredger along with some onsite discharge of water containing fine sediment from the dredger overflow. However, on assessment of these activities the experts have concluded that:
- Levels of oxygen and hydrogen sulphide would not be significantly affected by the dredging activity.
- Seawater quality could potentially be affected by dredger overspill sediments released back to the water column as a sediment plume, Dr. Robin Carter found. However, these impacts are in general identified as moderate to low and will be localised to the actual site and up to a distance of 1.8km from the dredge area.
- The main risks associated with dredging the ocean floor would be physical, such as increased water turbidity, according to the environmental studies commissioned for the project. Due to high turbulence at the sea bed in the proposed mining depths, it is determined that the quantity of organic matter and nutrient concentrations of the dredge area are low.
- Sulphur-absorbing bacteria – an important component of Namibia’s marine life – are typically located in the mud belt which is inshore of the mining sites of the licence area.
NMP’s mine permit is valid for 20 years. It is important to maintain a perspective on the relative scale of proposed activities. Assuming a thickness of 1m, then on an annual basis it is estimated that an area of approximately of 3 km2 would be dredged per year which equates to a total of approximately 60 km2 to be dredged over a 20 year life of mine or 2.68% of the total area of ML170 (area 2233 km2). The phosphate resources to be dredged are all located in sediment thickness of up to 3m. In accordance with the recommendation incorporated in the Environmental Management Plan a 10% residual of sediment will be retained within the resource recovery areas so as to leave blanket of local sediment to encourage re colonisation by marine fauna .
“We realise that our planned activities in the ocean could impact other ocean based industries in Namibia. We are accepting of the concerns of others and committed to constructive engagement directed towards mitigating any actual or perceived impact wherever possible and moreover, to minimising our impact on the marine environment,” Wellbeloved explains.