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Saturday 17 August 2019
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Phosphate dredging is safe, learn from Mexico

Recently, there has been propaganda that Marine Phosphate mining has not be done anywhere in the world. Such lies are damaging to the perceived industrialisation of Industrial Minerals such as Phosphate. In fact marine fish trawlers fishing the bethos are more damaging. Hence the Ministry of Environment should re-enforce fisheries to be subject to Clearance Certificates and be monitored according to the Environmental Management Act of 2007.
Marine Phosphate dredging is not a pollutant, at the moment the problem with the Clearance was procedures. Missing a procedures does not mean pollution.  In fact the Fishing industry should challenge the sufficiency of the Environmental Management Plan produced by NMP, and give a critical scientific analysis.

Two dredges on ship deck
transiting the Panama Canal
In June 1981 the twin dredges ‘Guaycura’ and ‘Pericue’ were christened in Baltimore for Roca Fosforica Mexicana SA de CF (Rofomex) of Mexico. The Rofomex dredges were named after two local Indian tribes, “joining the ancient traditions of the peninsula with modern technology”. The Ellicott Series 3000E electrically powered “Super-Dragon®” dredges were used in a phosphate mining project in LaPaz, Baja California, Mexico.
The project utilized 100 percent Mexican labor, dredging 2,000 tons of hard phosphate-bearing sand per hour, and transferring it to floating processing plants. Tailings were returned to the pond and the mineral underwent further processing in a shore-based plant.
Phosphate mining in Mexico
As Namibians are complaining about the Issuance of the Clearance Certificate for marine dredging of Phosphate, in Mexico at Santo Domingo, on the Pacific shore of the Baja California peninsula, Rofomex is dredging the marine phosphate sands since 80’s. According to Birch et al., (1978) in the Orange file at Ministry of Mines and Energy in Windhoek under Phosphate; this deposit found in Mexico is similar to the deposit in Namibian shelf. And it has been mined commercially off Baja, California (Birch et al., 1978).
Roca Fosforica Mexicana SA de CV (Rofomex) started up one phosphate mine in Baha California Sur in 1981 and another in 1982.
The Rofomex mines are strategic to Mexico as part of its program to improve productivity on Mexican farms by producing fertilizers.
At Santo Domingo, on the Pacific shore of the Baja California peninsula, Rofomex constructed a mine that  produce 1.5 million mt/yr of concentrates by dredge mining a beach sand deposit that grades about 4.5% P2O5 at a cutoff grade of 3% P2O5. Two Ellicott cutting head suction dredges feed ore to a barge-mounted primary flotation plant, which float in the mines area behind the dredges. Analysis of mining systems for the Santo Domingo project included consideration of bucket wheel excavators, draglines, scrapers, shovels, and dredges.
Selection of a dredge-based system hinged primarily on the fact that the other systems could not operate effectively below sea level. Low operating and maintenance costs prompted the final selection of floating hydraulic cutter suction dredges with 27-in diameter suction heads.

Lesson
In the mid/early 1980’s Rofomex, a Mexican state-owned company, dredged phosphate sands directly from the Bay of Magdalena.
Those who have claimed that offshore phosphate mining has never been done before, and is somehow impossible, are obviously off the mark.
Not only has phosphate mining/dredging been practiced in ocean waters, but it has been done in Mexico (the mine was eventually abandoned because of difficulties penetrating below a layer of calcium carbonate.
More important, the fact that the Mexican government was mining phosphate within the highly sensitive Bay of Magdalena tells us a number of interesting things.
It tells us that the government at that time viewed the benefits of mining in the bay to outweigh the environmental damage caused by the operation. Note that the Bay of Magdalena is considered one North America’s most biologically sensitive areas. The bay is known for whale calving and is a nutrient rich protected area that attracts a highly diverse group of species.
The Mexican government would not choose to mine here if it wasn’t very serious about establishing a strong domestic source of rock phosphate.
The government also likely viewed the environmental damage as relatively minimal since the process is a simple mechanical operation that doesn’t introduce any contaminants to the water. Dredging happens every day, all over the world, with relatively little environmental impact.
It also tells us that Rofomex decided the most economic method of mining this very large resource was by using a dredge, and extracting phosphate sands from underwater.
Much of the Santo Domingo claim lay above the water line, but Rofomex did not try to mine on dry ground. This point would support the claims made by Rofomex management, and which are supported by independent due-diligence, that dredging phosphate sands is less expensive than land-based extraction (even in this case when the land-based resource had little or no overburden).
The Rofomex example took place approximately 30 years ago, and of course much has changed in the intervening period, but no marine life was affected.
The current atmosphere surrounding the ECC for NMP, demonstrates that the opposition or affected party lack an in-depth of marine exploration and mining.
This demonstrated with spreading fear to public that such exercise of marine dredging has not be done before anywhere in the world.
The Namibian Government should send a team to visit the marine dredging in Mexico in order to have a first-hand experience that may help in decision making for Namibia. And probably use the data generated from marine monitoring as a modelling tool for Namibia.
What next
It is important that the Environmental Management Plan produced NMP, be reviewed to accommodate the issues raised by the concerned group, in order to make sure that strict environmental management are enforce for NMP to dredge the sea floor.
However this is only possible once the concerned group has identified loop holes in the EMP produced by NMP. Because the issue of saying the ‘Environmental Commissioner did not follow the procedure’ in issuance of the Clearance Certificate of does not constitute a scientific analysis to the project, rather an administration issue, which does not result to pollution.
Hence the procedure can be corrected.  But the concerned group should give a critical analysis of the EMP produced by NMP. Government should allow NMP to carryout test mining, in order to ascertain the likely environmental effects of dredging. And such data to be generated should be used as bench mark for future sea floor marine exploration and mining.
NMP in its EMP has highlighted its continuous monitoring by mapping the sediment plumes.
This method is similar to the current procedure followed by Namport in its EMP during the dredging of the port expansion situated close to the lagoon. If fisheries is concerned about the effects of dredging on marine life, what happened to diamond dredging and port expansion at Walvis Bay, marine phosphate mining is not dangerous, it is rather a management of risk, similar to any other mining activities like diamond dredging.
And also, it is important to note that Ministry of Environment has adequate knowledge on environmental monitoring and management, through its Environmental Management Act of 2007.
A country can industrialize if its natural resources are adequately utilized. Production of phosphate will realize Namibia’s strategy on Mineral beneficiation because the by products from the phosphate industry will spear head industrialization of by-products.
In addition fertilizer industry will assist Government to provide cheap fertilizer to increase the crop yield and create a revolution in the agriculture sector. It is time we educate the public than spread fear.

Mulife Siyambango is a local Industrial Geologist, with a Master of Science in Industrial Rocks and Minerals (Exeter), an MBA in strategic Management (Maastricht), and current part time student LLM-Natural Resource Law (Univ. Dundee). He is the Centre Director at Centre for Geosciences Research in Windhoek.




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