Improved Methods for Determining Soil-Atmosphere Flux Boundary Conditions at Mine Waste Repositories

矿山废物库的成功运作和关闭需要准确地量化地表水预算，以控制大气降水渗入废物分布。表面净入渗的速度最终会产生内部渗漏，释放出可能威胁下游受体的渗滤液。最近在加拿大活跃和回收的矿场以及加拿大公司经营的国际矿场进行的现场规模观察表明，目前用于计算废石场和尾矿库等矿山废物沉积物的渗透率的预测模型是不可接受的。例如，根据不列颠哥伦比亚省Equity Silver矿排水收集沟中测量的流量直接确定的净入渗率，被发现比使用目前的土壤-大气模拟方法预测的入渗率大三倍。这里提出的研究计划的全球目标是调查这些误差的原因，并改进现有的土壤-大气方法，以估计矿山废物储存库的地表通量边界条件。*申请人在过去六年中进行的所有研究都是在矿山废物管理领域。研究方案的目标一直是开发新技术，以改善矿山废物管理、关闭和减少长期环境责任。这些目标是通过高素质人员的培训和创新实现的。*这项应用的短期目标是推进新的技术，为改进土壤-大气通量边界方法提供田间尺度蒸发通量的精确测量。该研究计划的长期目标将是提高研究人员和从业人员观察、预测和设计尾矿和废石蓄水池覆盖系统的能力。此外，长期目标将是继续培训HQP，将研究结果传播到适当的期刊和会议记录中，并最终协助将研究结果落实到实践中。计划培训1名硕士和2名博士生和研究助理(1/2次)。开发和实施在此提出的新技术的最终目标将是在地表水管理和减少环境责任方面改进矿山废物储存库的设计和性能。

Successful operation and closure of mine waste repositories require accurate quantification of the surface water budget that controls the infiltration of meteoric water into the waste profile. The rate of net surface infiltration ultimately generates internal seepage with the release of potential leachates that may threaten downstream receptors. Recent field scale observations at both active and reclaimed mine sites in Canada, as well as international sites operated by Canadian companies, have shown current predictive models used to calculate infiltration rates for mine waste deposits such as waste rock dumps and tailings impoundments are unacceptable. For example, net infiltration rates determined directly on the basis of measured flow rates in the drainage collection ditches at Equity Silver mine in British Columbia have been found to be three fold greater than infiltration rates predicted using the current soil-atmosphere modelling methodology. The global objective of the research program proposed here is to investigate the reasons for these errors and to improve the existing soil-atmosphere methods currently available for estimating surface flux boundary conditions at mine waste repositories.****All of the research carried out by the applicant over the past six years has been in the area of mine waste management. The objective of the research programs has been to develop new technologies for improved mine waste management, closure and the reduction of long-term environmental liabilities. These objectives have been achieved through the training and innovation of highly qualified personnel.***The short-term goal of this application is to advance new techniques that provide precise measurements of field scale evaporative fluxes for improving soil-atmosphere flux boundary methods. The long-term objective of the research program will be to improve the capability of researchers and practitioners to observe, predict and design cover systems for mine tailings and waste rock impoundments. In addition, the long-term objective will be to continue training of HQPs, disseminate the results of the research into appropriate journals and conference proceedings, and finally to assist with the implementation of the research results into practice. The training of 1 MSc and 2 PhD students and Research Associate (½ time) is planned. The ultimate objective for developing and implementing the new techniques proposed here will be to improve the design and performance of mine waste repositories with respect to surface water management and the reduction of environmental liabilities.**