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The Orca Quarry began production on February 20, 2007, and the first Panamax freighter was loaded and dispatched for San Francisco Bay on April 1, 2007.
Extraction will occur in phases, moving from north to south. Scrapers remove the sand and gravel, feeding it to a portable dump hopper that directs the sand and gravel onto a conveyor system for transport to the processing plant. Extraction will be to a depth of up to 60 m and will occur only above the groundwater table.
Progressive reclamation will occur throughout operations, beginning after year 4, with each extraction phase being graded and then covered with soil removed from the next phase of the site. Silt (fine sand produced as a by-product) and other organic materials available will be added to the soil as it is spread. Local plant and tree species will then be planted. At closure, all structures on land and in the marine environment will be removed, unless used for another approved purpose. All disturbed land will be reclaimed.
The processing plant separates the material into three products: coarse and fine gravel and concrete sand. The processing plant consists of primary screening with a crushing circuit for oversize gravel, secondary screening, washing and sand classification, product storage stockpiles and a product reclaim system. The processing plant and product stockpiles will be located at the north end of the property in the area of the existing Hartford Pit. Four product stockpiles are required, two for sand and one each for large and small gravels. A minimal amount of raw material is oversized, that is larger than 1 inch (25 mm) and will require crushing and blending back with the sand and gravel stream. The only by-product from the process is silt (very fine sand less than 75 microns in size) which must be removed for product integrity in the washing stages. However, this silt becomes a valuable soil additive in the reclamation of the land.
Process water containing silt passes through a thickener and is directed through filter presses allowing clean water from the washing process to be recycled in the plant to minimize groundwater usage. Make-up water is supplied from groundwater via a well. There will be no surface water, or wastewater, discharged from the site. Fines extracted through the filter presses will be used in the reclamation of the pit. This progressive approach to the silt recovery and water recirculation eliminates the need for ponds to be created to store these materials.
Aggregate products from the Quarry are transported via conveyor to the ships or barges on the foreshore, a distance of approximately 1,700 m. This conveyor sits on the ground, passing underneath Highway 19 and the Rupert Main logging road in culverts. Underpasses suitable for large animals have been included in the design that will allow them to travel under the conveyor between the Rupert Main and the foreshore. The reclaim and conveying system will have a capacity of up to 5,000 tonnes per hour.
The conveyor is elevated above the foreshore on groups of piles, spaced 35 m apart and extending 485 m from the shore to a quadrant ship loader. The ship berth consists of discrete piled structures which will not impede the flow of water or movement of marine life. |