内陆核电站拟选厂址附近浅层地下水水化学特征及同位素指示意义

以江西何魁核电站拟选厂址附近为研究区,采集地表水样品5个和浅层地下水(泉水和井水)样品37个,进行水化学及同位素分析。结果表明:拟选址周边地表水为淡水,呈弱碱性,主要阴、阳离子为HCO₃^-和Ca²⁺;泉水为弱酸性,主要阴、阳离子为HCO₃^-和Na⁺;井水呈弱碱性,主要阴、阳离子为HCO₃^-、Cl^-、SO₄^2-和Ca²⁺、Na⁺。水-岩相互作用和大气降水是影响该区浅层地下水化学特征的主要因素,Na⁺和K⁺来源于盐岩和硅酸岩溶解,Ca²⁺来源于碳酸岩和石膏溶解,HCO₃^-、Cl^-和SO₄^2-分别来源于碳酸岩、盐岩和石膏溶解。饱和指数分析...

Hydrogeochemical characteristics and isotopic indication of shallow groundwater in the vicinity of a proposed inland nuclear power plant

Nuclear power can alleviate the pressure of global energy demand. However, the resources suitable for constructing nuclear power plants (NPPs) in coastal areas are limited, and the development of nuclear power construction in the inland area has become one of the trends. It is essential to master the characteristics of the water environment near the NPPs for the site selection, planning, and design of NPPs. In this study, the vicinity of the proposed site of Hekui NPP in Jiangxi Province was taken as the study area, and the shallow groundwater was chosen as the research object. Five surface water and thirty-seven shallow groundwater samples, including spring and well water, were collected for hydrochemical and isotopic analysis. The major results obtained from this study were as follows: the surface water in the study area was fresh water and weakly alkaline, and the major anions and cations were HCO3- and Ca2+; the spring water was weakly acidic, and the major anions and cations were HCO3- and Na+; the well water was weakly alkaline, and the major anions and cations were HCO3-, Cl-, SO42-, and Ca2+and Na+. Water-rock interaction and atmospheric precipitation were the dominant factors affecting the chemical characteristics of shallow groundwater in this area. Na+ and K+ came from halite and silicate dissolution. Ca2+ came from carbonate and gypsum dissolution. HCO3-, Cl-, and SO42- were from carbonate, halite, and gypsum dissolution, respectively. The saturation index results showed that major components of shallow groundwater were from the weathering and dissolution of silicate and carbonate. Stable hydrogen and oxygen isotope compositions showed that well water was mainly recharged by atmospheric precipitation and affected by mixing reactions. Groundwater exchanged with hydrocarbon and silicate minerals, CO2, wall rocks, and clay. Unlike spring water and well water, surface water was significantly affected by evaporation. Tritium concentration was between 2.1-3.6 TU, and it was speculated that the age of shallow groundwater was over 50 years. This study provides not only the natural environment background value for the proposed site of Hekui Inland NPP but also a theoretical basis for the development and utilization of groundwater resources, as well as environmental protection and the optimization of the design scheme for the construction of the NPP. Meanwhile, this study has reference significance for water pollution in emergencies.