Developing environmental regulator capability in source apportionment and remediation of mine pollution

在19世纪50年代，英国是世界领先的铅、锌和铜等贵重金属生产国。到20世纪20年代，经济衰退和在国外发现更大的金属矿藏迫使大多数金属矿关闭。然而，这些废弃矿山的固体废物和受污染的排水，在这个行业衰落近一百年后的今天，仍然是水质和生态系统退化的主要原因。这个问题在威尔士尤为严重，在那里超过1300个已知的废弃矿井导致高达19%的河流不符合环境标准。解决这一问题需要三大创新。首先，我们需要开发方法来系统地筛选受采矿影响的河流集水区，以准确识别和量化污染源，以便优先考虑修复地点。其次，我们需要开发建模工具，以便从改善水质的角度来评估不同补救方法（如矿井水处理）的潜在有效性。第三，我们需要开发新的方法来治疗、隔离或消除已确定的矿山污染源。本项目通过分别在威尔士中部和北部的南特Cwmnewyddion和Afon Crafnant集水区进行案例研究，解决了前两项创新。(1)创新。矿山污染源识别需要同步测量河流流量和金属浓度，以便计算河流金属负荷。对河流集水区的多种金属负荷估算提供了对矿山污染源的概述（或概要）评估。对集水区的河流金属负荷测量得越多，就能提取出更多关于矿山污染源的细节，以便制定补救计划。然而，威尔士自然资源部（和其他环境监管机构）目前用于确定矿山污染源的方法并没有提供必要的空间细节，以捕获整个集水区所有可能的矿山污染源。为了克服这个问题，该项目将展示一种创新的方法，以以前无法实现的空间分辨率识别污染源。具体来说，该项目将使用注入河流的水文示踪剂来计算河流中的金属负荷。使用示踪剂的主要优点是，它在可以收集的样品的准确性和数量上提供了数量级的提高，因此提供了查明污染源所需的空间细节水平。创新(2)目前在英国没有方法来评估不同矿山污染修复方案的潜在有效性。这部分是由于缺乏运行修复模型所需的适当数据。该项目将展示如何利用水文示踪剂研究所得的数据来开发一种建模工具，能够模拟假设的补救方案对水质的影响。这将确保补救计划的设计和目标是尽可能产生最大的环境和经济效益。该项目是自然资源威尔士（NRW）和利物浦约翰摩尔斯大学之间的合作努力，并建立在以前rcuk资助的研究（NE/M017486/1; FENAC/2016/11/008；钻石SP17227）广泛关注改善受采矿影响的集水区水质。主要目标是发展北威州在使用水文示踪剂和修复模型方面的专业知识，以便他们能够优先考虑那些矿区进行修复，从而提供最大的环境和经济效益。据估计，清理被矿山废物污染的河流将在25年内使威尔士经济受益3000万至4900万英镑，其途径包括：增加娱乐活动（如钓鱼）；旅游;改善公共供水、农业、工业和发电用水的水质；创造就业机会;通过提供国内和国际的研究机会。

In the 1850s, the UK was the world's leading producer of valuable metals such as lead, zinc and copper. Economic downturn and the discovery of larger metal deposits abroad forced the closure of most metal mines by the 1920s. However, solid waste and polluted drainage from these abandoned mines remains a major cause of water quality and ecosystem degradation today, almost one hundred years after the decline of this industry. The problem is particularly acute in Wales where over 1300 known abandoned mines cause up to 19% of rivers to fail environmental standards.Three major innovations are required to tackle this problem. First, we need to develop methods to systematically screen mining-impacted river catchments to accurately identify and quantify sources of pollution in order to prioritise sites for remediation. Second, we need to develop modelling tools that allow the potential effectiveness of different remedial approaches (such as mine water treatment) to be evaluated in terms of improvements to water quality. Third, we need to develop novel approaches to treat, isolate or remove identified sources of mine pollution. This project addresses the first two of these innovations through case studies in the Nant Cwmnewyddion and Afon Crafnant catchments in central and north Wales, respectively.Innovation (1). Source identification of mine pollution requires synchronous measures of streamflow and metal concentrations in order to calculate stream metal loads. Multiple metal loading estimates across a river catchment provides an overview (or synoptic) assessment of mine pollution sources. The more measurements of stream metal loads across a catchment, the more detail on mine pollution sources can be extracted for remediation planning. However, the current approach used by Natural Resources Wales (and other environmental regulators) for identifying sources of mine pollution does not provide the necessary spatial detail to capture all possible sources of mine pollution across a catchment. To overcome this issue, this project will demonstrate an innovative approach for identifying sources of pollution at a previously unachievable spatial resolution. Specifically, the project will use a hydrologic tracer injected into the river to calculate stream metal loads. The major advantage of using a tracer is that it provides order-of-magnitude improvements in the accuracy and number of samples that can be collected and therefore delivers the level of spatial detail required to pinpoint sources of pollution.Innovation (2) There is currently no method in the UK for evaluating the potential effectiveness of different mine pollution remediation scenarios. This is partly due to the lack of appropriate data required to run remediation models. This project will demonstrate how data derived from hydrologic tracer studies can be used to develop a modelling tool capable of simulating the effect of hypothetical remediation scenarios on water quality. This will ensure that remediation schemes are designed and targeted to yield the most environmental and economic benefit possible.This project is a collaborative effort between Natural Resources Wales (NRW) and Liverpool John Moores University and builds on previous RCUK-funded research (NE/M017486/1; FENAC/2016/11/008; Diamond SP17227) broadly concerned with improving water quality in mining-impacted catchments. The key aim is to develop NRW expertise in the use of hydrologic tracers and remediation modelling so that they can prioritise those mine sites for remediation that will deliver the most environmental and economic benefit. It is estimated that cleaning up rivers polluted by mine wastes could benefit the Welsh economy by £30-£49M over 25 years through: increased recreational activity (e.g. fishing); tourism; enhanced water quality for public supply, agriculture, industry and power generation; job creation; and by providing national and international research opportunities.