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The proposed wind fence concepts balance dust suppression efficacy, and constructability to the best
ability in current stage, and minimal interference with rail access, stacker/reclaimer operations, ship
loading, and vehicle pathways:
1. Full enclosure: A complete perimeter porous wind fence surrounding the main stockpile zones
(e.g., 80–100 ft high, 50% porosity). This option maximizes wind blocking from all directions,
creating extensive low-velocity recirculation zones over the piles to suppress entrainment across
the full 360°. It offers the highest potential dust reduction but may pose greater challenges for
operations, access, and ventilation.
2. Semi-enclosed or U-shaped fence: An open-sided arrangement focusing on the upwind
exposures (primarily southern and southwestern sides) while leaving the northern or river-facing
side partially open. This creates sheltered zones for predominant SW and SSE winds, promoting
turbulence dissipation and downward deflection to reduce particle lift-off. It provides strong
protection against the most frequent directions with better operational flexibility and lower material
costs than full enclosure.
3. Targeted segments on the port side and bottom side: Focused barriers along the southern
("bottom" relative to dominant SW/SSE inflow) and western/port-side perimeters only. Taller or
higher-porosity sections target SW and SSE winds, with shorter extensions addressing WNW
flows. This modular, effective approach minimizes disruption to core activities while prioritizing
dust control toward key downwind receptors (north/northeast under SW/SSE; south under WNW).
CFD simulations incorporate the wind rose (frequency-weighted directions and speeds) to compare
baseline fugitive dust dispersion against each fenced scenario. The designs emphasize passive porous
barriers that reduce near-surface velocities, attenuate shear, and limit downwind particle transport.
Aerodynamic Coverage and Velocity Recovery Profile
While the terminal's main stockpile and handling area spans approximately 1,700 feet in the relevant
downwind direction under predominant southwest (SW) winds, the effective shelter provided by an 80-
foot-high porous wind fence extends reliably across much of this distance, though with a gradual
reduction in protection intensity.
For a 50% porous fence, established engineering guidelines and windbreak research (from agricultural,
environmental, and industrial applications) indicate that significant wind speed reduction typically persists
over 15–20 times the fence height (H) downwind. This corresponds to:
Optimal or peak shelter often around 10–15H (where velocity reductions can reach 50–80% or
more near the surface).
Adequate protection (e.g., meaningful suppression of shear and entrainment) extending to about
18–20H.
With H = 80 ft:
conditions).
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world factors like terrain flatness, coastal turbulence, and partial wind recovery.
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