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

要成功地运作和关闭矿山废物储存库，就需要准确地量化地表水预算，以控制大气降水渗入废物的情况。净表面渗透率最终产生内部渗漏，释放出可能威胁下游受体的潜在沥滤液。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实地规模观察表明，目前用于计算废石堆和尾矿库等矿山废物沉积物渗透率的预测模型是不可接受的。例如，在不列颠哥伦比亚省的Equity银的排水收集沟中，根据测得的流量直接确定的净渗透率比使用当前土壤-大气建模方法预测的渗透率大三倍。这里提出的研究计划的全球目标是调查这些错误的原因，并改善现有的土壤-大气方法目前可用于估计地表通量边界条件在矿山废物库。

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.