Screenshot of a numerical model for underwater noise

Don Diego underwater phosphate mining

Our state-of-the-art methods to assess marine sediment behaviour and sound propagation from phosphate extraction at Don Diego, Mexico played an important part in the overall Environmental Impact Assessment (EIA).

Our independent scientific studies of marine sediment plume dispersion and the propagation of underwater sound from phosphate extraction at Don Diego, Mexico played an important part in the overall Environmental Impact Assessment (EIA).

Marine phosphate, a strategic resource to help increase food production

Marine phosphate is of increasing international interest as a strategic reserve of agricultural fertiliser. At present no major marine phosphate deposits are being developed, and there is a high level of scrutiny of emerging proposals. The proposed Don Diego dredging area is located in waters 70-90 m deep and 40 km offshore. The area of highest phosphate is located in the Mexican Exclusive Economic Zone. Phosphate is a fundamental component of agricultural fertiliser, and this potential major new source of marine phosphate could help increase food production in Mexico and allow the country to become a phosphate exporter.

Independent scientific studies for the proposed dredging area

An Environmental Impact Assessment (EIA) for the proposed dredging and recovery of marine phosphate sands from the Don Diego deposit was required. Key issues for the EIA 

  • included the potential for sediments released from the extraction processes, to disperse widely and settle on areas of biodiversity interest.
  • concern over the potential for underwater sound to affect marine mammals in the region.

HR Wallingford carried out independent scientific studies of marine sediment plume dispersion and the propagation of underwater sound from the extraction processes. We applied our state-of-the-art computer models of marine sediment behaviour (SEDTRAIL-3D) and underwater sound propagation (HAMMER).

Assess marine sediment behaviour and underwater sound propagation

We applied our state-of-the-art assessment methods to marine sediment behaviour and sound propagation. The results provide a clear understanding of some of the key effects of marine phosphate recovery.

Evidence-based EIA

The modelling results provide a clear understanding of the physical processes in the phosphate recovery area. These have formed the basis of ecological assessments undertaken within the EIA. Our work ensured that regulators have the best available evidence to inform their decision-making.