Knowledge Center / Surface Disposal Project Experience
US BORAX,
BORON, CALIFORNIA, USA
This study was performed to determine long-term disposal options for Borax’s waste material. The study involved the removal and relocation of solids from the plant waste ponds to an alternate area. Golder PasteTec™ attempted to reduce the costs and improve operations by limiting additional ponds. The removed solids would be pumped as thickened slurry to an alternate deposition area, where they would ideally desiccate with minimal water bleed. Several options were produced for transporting and storing the solids and the most suitable method was a mobile mixing/pumping method.
THREE SISTERS PROJECT,
CANMORE, ALBERTA, CANADA
This project involved work between Golder PasteTec™ and Golder Associates Ltd. (GAL – Calgary). Golder PasteTec™ excavated coal spoils and other waste materials over a three-year period for disposal underground. The waste material was thickened into a paste, mixed with cement and inserted underground into abandoned coal mines. The goal of this project was to stabilize the old coal mines so that houses could be built on the land and also allowed for the disposal of the coal spoils underground.
SKEENA PROJECT,
PRINCE RUPERT, BRITISH COLUMBIA, CANADA
A PCB dredge and disposal system was designed and built by Golder PasteTec™. Golder PasteTec™ completed a fast-track design/build/operate project for a PCB clean-up project in Prince Rupert, BC. Marine shoreline sediments contaminated with PCB were dredged, screened, sorted and deposited in final ponds, while carrier water was treated in clarifier prior to release to the environemnet. Strict guidelines for release were dictated by the Department of Fisheries and Oceans. Production rate designed for 400 m3/hr included mineral and organic solids consisting of large cobble (> 200 mm), hogfuel/woodchips (long strands to 5 mm chips), fine saw dust, stones and sediments to <1 micron.
COLDSTRIP POWER STATION,
BILLINGS, MONTANA, USA
This project in Billings, Montana was conducted for PPL Montana. Golder PasteTec™ performed the feasibility study, pilot plant testing, flow loop, geotechnical testing, detailed engineering and is currently finishing construction of a 73 tph flyash Surface Disposal system. The plant will reduce the amount of water in the effluent holding pond and will significantly reduce PPL’s current issues with groundwater contamination and seepage from the EHP.
BULYANHULU GOLD PROJECT
This project for Barrick Gold involved Golder PasteTec™ working with SNC-Lavalin to complete the detailed engineering of a 180 tph batch paste plant which will have the capability to dispose of tailings underground as backfill or on surface in a ‘stacked’ paste form. Golder PasteTec™ performed the process and geotechnical design and SNC-Lavalin provided the structural, civil, electrical and instrumentation packages. Golder PasteTec™ designed the underground distribution system, which utilizes gravity to feed all areas of the mine. Construction and commissioning of the plant was completed in March 2001.
ROCK CREEK,
MONTANA, USA
This Asarco project was one of the first full-scale feasibility studies completed on the use of paste for Surface Disposal. A 10,000 tpd Copper project was investigating the potential for alternative tailings management schemes and detailed cost estimates were made based on paste technology and traditional sub-aqueous disposal methods. Laboratory testing was followed by field trials on the behavior of the material when placed on surface and included leachate collection and trafficability.
The results showed that the capital cost of the project could be significantly reduced through the use of paste technology although the operating costs of the paste option resulted in a slightly higher Net Present Cost for the paste option over the projected 30 year mine life.
GREECE PROJECT
At the request of the client, Golder PasteTec™ investigated the use of paste for Surface Disposal at a gold project located in Northern Greece. A conceptual design was proposed that reduced the footprint of the facility, reduced the volume of the containment facility and greatly reduced the reclamation costs for a relatively short-term project. Favourable geometry indicated savings of 20% over the cost of a traditional impoundment.
SAN BARTOLOME PROJECT
This project for Empresa Minera Manquiri S.A.involved Golder PasteTec™ working with Fluor Inc. to complete the detailed engineering of a 300 tph Surface Disposal paste pipeline and pumping system, which will have the capability to transport paste through a long pipeline via pumping. The pumps were designed to overcome a 20% incline to reach the final deposition area. Golder PasteTec™ performed the process and transport system design and Fluor Inc. provided the structural, civil, and electrical packages. Golder PasteTec™ designed the paste pipelines.
ESCONDIDA PROJECT
This project for Minera Escondida TDA involved Golder PasteTec™ performing the process engineering and pipeline design of a 4500 tph Surface Disposal paste plant which will have the capability to dispose of tailings surface in a ‘stacked’ paste form. Water conservation was a key requirement of this project due to the extreme climate of the area. There were several paste thickeners involved in the process design. Golder PasteTec™ designed the paste distribution system, which utilizes pumping of paste through long pipelines.
CODELCO NORTE,
CHILE, SOUTH AMERICA
This project for Codelco Norte in Chile involved Golder PasteTec™ doing the complete detailed process and pipeline design for a Surface Disposal paste plant. The mine is located in the desert thus water conservation is important. This plant will have the capability to dispose of tailings on the surface in a ‘stacked’ paste form which will hold its water. The paste will also require less water for deposition than conventional slurry. This design involved a ring of paste thickeners with pumping and spigotting around the deposition area.
