Environmental Aspects of Phosphate and Potash Mining

Environmental Aspects of Phosphate and Potash MiningSolution Mining Pump and Pipeline Monitoring and Control SystemThe PCS Patience Lake Division, located inSaskatchewan, Canada, extracts potash from a floodedconventional underground mine using a solution miningmethod. The extraction method uses a system ofbrine injection and recovery well linked with pipelinesto cooling and precipitation ponds adjacent to the processingplant. The wells are scattered over a wide arearequiring an extensive network of pipelines.To avoid the potential risk of failure and release ofbrine a number of design features and control andmonitoring techniques have been employed. Brinesare transported through buried, large diameter HDPEpipes at a low pressure. The buried pipeline is lined,with drainage manholes located at low points to detectleaks. A monitoring system is in place to detect spillagesat the wells and a containment system using bunds(earth walls) has been constructed around the recoverywell site.Visual inspection of the system is conducted each shift,while an electromagnetic survey is conducted at regularintervals to detect hidden leaks from buriedpipelines or ponds. PCS has developed this method thatallows changes in ground conductivity, caused by thepresence of salts, between surveys at different times tobe detected.Spillage detectors - Potash Corporation of Saskatchewan(PCS), Patience Lake, CanadaRecovery of potash from ponds - Potash Corporation ofSaskatchewan (PCS), Patience Lake, CanadaEmergency spillage recovery pump, Potash Corporation ofSaskatchewan (PCS), Patience Lake, CanadaHeating potash brine prior to injection - PotashCorporation of Saskatchewan (PCS), Patience Lake,CanadaAir EmissionsEffects on air quality tend to be of a localized natureand are largely related to the generation and emissionof dust particulates by blasting, excavation and equipmentmovement or exhaust gases and particulatesfrom engines. Control techniques are discussed inSection 3.1.Underground operations control exhaust particulatesby installing particulate filters on the exhausts ofmobile equipment. Retrofitting equipment with new,more efficient and cleaner engines also reducesexhaust particulate and gas emissions, as well as contributingto reduced fuel consumption andmaintenance costs.