Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Roma 1, Via di Vigna Murata, 605 - 00143 Roma, Italy.
Dipartimento di Scienze della Terra, Università di Firenze, via G. La Pira 4, 50121 Firenze, Italy; CNR - Istituto di Geoscienze e Scienze della Terra, via G. La Pira 4, 50121 Firenze, Italy.
Environ Pollut. 2019 Oct;253:525-537. doi: 10.1016/j.envpol.2019.07.063. Epub 2019 Jul 13.
659 water samples from springs and wells in the Sabatini and Vicano-Cimino Volcanic Districts (central Italy) were analyzed for arsenic (As), fluoride (F) and radon (Rn) concentrations. Waters mostly sourced from a shallow and cold aquifer hosted within volcanic rocks, which represents the main public drinking water supply. Cold waters from perched aquifers within sedimentary formations and thermal waters related to a deep hydrothermal reservoir were also analyzed. The highest concentrations of As and F were measured in the thermal waters and attributed to their enhanced mobility during water-rock interaction processes at hydrothermal temperatures. Relatively high concentrations of As and F were also recorded in those springs and wells discharging from the volcanic aquifer, whereas waters hosted in the sedimentary units showed significantly lower contents. About 60% (As) and 25% (F) of cold waters from the volcanic aquifer exceeded the maximum allowable concentrations for human consumption. Such anomalously high levels of geogenic pollutants were caused by mixing with fluids upwelling through faulted zones from the hydrothermal reservoir. Chemical weathering of volcanic rocks and groundwater flow path were also considered to contribute to the observed concentrations. Cold waters from the volcanic aquifer showed the highest Rn concentrations, resulting from the high contents of Rn-generating radionuclides in the volcanic units. Approximately 22% of these waters exceeded the recommended value for human consumption. A specific Quality Index (QI), comprised between 1 (very low) and 4 (very high), was computed for each water on the basis of As, F and Rn concentrations and visualized through a spatial distribution map processed by means of geostatistical techniques. This map and the specific As, F and Rn maps can be regarded as useful tools for water management by local authorities to both improve intervention plans in contaminated sectors and identify new water resources suitable for human consumption.
对来自意大利中部萨巴蒂尼和维卡诺-奇米诺火山地区的 659 个泉水和井水样本进行了砷（As）、氟化物（F）和氡（Rn）浓度分析。这些水主要来自火山岩中浅层和低温含水层，是主要的公共饮用水源。还分析了来自沉积地层中高位蓄水层的冷水和与深部热液储层有关的温泉水。温泉水中的砷和氟浓度最高，这归因于在热液温度下水岩相互作用过程中增强了它们的迁移性。从火山含水层中排放的泉水和水井中也记录到了相对较高浓度的砷和氟，而在沉积单元中储存的水则显示出明显较低的含量。大约 60%（As）和 25%（F）的来自火山含水层的冷水超过了人类消费的最大允许浓度。这种异常高的地球成因污染物水平是由于与通过断层从热液储层上升的流体混合造成的。火山岩的化学风化和地下水流动路径也被认为是造成观察到的浓度的原因。来自火山含水层的冷水具有最高的 Rn 浓度，这是由于火山单元中产生 Rn 的放射性核素含量高。这些水大约有 22%超过了人类消费的推荐值。根据 As、F 和 Rn 的浓度，为每一种水计算了一个特定的质量指数（QI），范围在 1（非常低）到 4（非常高）之间，并通过利用地质统计学技术处理的空间分布图进行可视化。该地图和特定的 As、F 和 Rn 地图可被视为地方当局进行水资源管理的有用工具，既可以改进污染区域的干预计划，也可以确定适合人类消费的新水资源。
