Abstract：
Metal mining in the Extremadura region was very important in the 19th and 20th centuries. However, due to different reasons the great majority of mines ceased operations, leading to plenty of abandoned mining sites, most of them with on-site waste dumps. Although metal extraction is not radioactive per se, it is considered a NORM activity. In this study, three former mining sites, in which Pb-V-Zn-Ag, Pb-Ag, and Pb-Zn were extracted, were selected to assess the radiological impact on the population and the environment. The external γ exposure was estimated by determining the effective dose and elaborating isodose maps of the sites. The presence of the mining sites increased up to 0.41 mSv/y the effective dose over the surrounding background, which is below the reference value of 1 mSv/y. In only one mining site, the uranium and radium activity concentration of waste dumps were higher than the surrounding soil. The soil to plant (wild grass) transfer factors were similar to other reported values without the influence of NORM activities. So, no enhanced transfer of radionuclides was observed. The radiological impact on the environment was assessed by the risk to non-human biota using the tiered approach developed in ERICA Tool. The sum of the risk quotients of all considered radionuclides in the most conservative Tier 1 was below 1. Total dose rates for several terrestrial Reference Animal and Plants (RAPs) were estimated using Tier 3, obtaining values below 40 µGy/h. Therefore, the impact on non-human biota can be considered as negligible.
摘要：
埃斯特雷马杜拉地区的金属开采在19世纪和20世纪非常重要。然而,由于不同的原因，绝大多数矿山停止运营，导致大量废弃的采矿场，他们中的大多数都有现场垃圾堆。虽然金属提取本身不是放射性的，它被认为是NORM活动。在这项研究中,三个以前的采矿场,其中Pb-V-Zn-Ag,Pb-Ag,并提取了铅锌，被选中评估对人口和环境的放射性影响。通过确定有效剂量并详细说明站点的等剂量图来估计外部γ暴露。采矿地点的存在增加到0.41mSv/y有效剂量超过周围背景，低于1mSv/y的参考值。只有一个矿区,垃圾场的铀和镭活性浓度高于周围土壤。土壤到植物（野生草）的转移因子与其他报道的值相似，没有NORM活性的影响。所以,未观察到放射性核素转移增强.使用ERICA工具中开发的分层方法，通过对非人类生物群的风险评估了放射性对环境的影响。在最保守的1级中，所有考虑的放射性核素的风险商的总和低于1。使用Tier3估算了几种陆地参考动植物（RAP）的总剂量率，获得的值低于40µGy/h。因此,对非人类生物群的影响可以认为是微不足道的。
