在高放废物地质处置库选址和性能评价过程中，水文地质条件是其中最要的因素之一，而包气带土壤渗透性又是水文地质研究中的核心问题之一。甘肃北山地区是我国高放废物地质处置库场址首选预选区，新场-向阳山地段是北山预选区的重点候选场址之一。为查明该地区包气带土壤渗透性特征，本文选用双环法和Guelph入渗仪法两种试验方法开展包气带土壤渗透性的研究并综合分析了影响土壤渗透性的主要因素。结果表明：（1）区内包气带土壤渗透性能差异较大。总体来看，沟谷地带的土壤饱和渗透系数(Kfs)大于缓坡地带，缓坡地带Kfs大于平滩地带；（2）构造影响带Kfs很大，不同构造影响带Kfs存在一定的差异；（3）研究区包气带土壤渗透性的最主要影响因素是粒径> 0.5 mm的粗砂与粒径< 0.1 mm的极细砂、粉粒及黏粒含量，而粒径为0.5~0.1 mm的中砂、细砂含量影响最小。
In selecting and evaluating a new dump site for disposal of high-level radioactive waste (HLW) repository, its hydrogeology condition is one of the most important factors. Moreover, soil permeability of the aeration zone is one of the key issues in the study of hydrogeology, affecting water infiltration, runoff and evapotranspiration in the surface soil layer and their distribution relations. Analysis of soil permeability of the aeration zone helps understand the mechanism of groundwater formation. Beishan in Gansu Province is a preselected priority region for disposal of China’s HLW, while Xinchang-Xiangyangshan is a preselected priority site. For that end, investigations were carried out on soil permeability of the aeration zone in that preselected site, using the double ring method and and a Guelph infiltration meter in-situ. With the aid of software SPSS 19.0, soil organic matter, initial soil water content, soil pH, soil bulk density, soil total ion content and soil particle size distribution were selected as 6 main affecting factors for principal component analysis. This project was aimed at acquiring data for in-depth study on characteristics of soil water movement and formation and circulation of groundwater in the area, so as to provide some scientific basis for site determination and performance evaluation of the preselected area. The following knowledge and results were obtained：(1) horizontal distribution of permeability coefficients of the soil aeration zone of Xinchang-Xiangyangsan was characterized by ① soil permeability varied sharply with the location; ② in terms of soil saturated hydraulic conductivity (Kfs), various geomorphic units followed an order of gully (4×10-5 m s-1) > slow slope (1.6×10-5 m s-1) > flat land (7.69×10-6 m s-1). Therefore，it could be inferred that gullies are the main area where rainwater infiltrates and permeates into deep soil to form groundwater, and an area that should be crossed out from the list of candidates of HLW dump sites, because of its active groundwater; ③ Kfs is higher at the Xinchang fault belt than at the Jijicao fault belt, being on average 2.75×10-4 m s-1 and 9.37×10-5 m s-1, respectively. So large-scaled fault belts should also be crossed out from the list due to its highly active groundwater; ④ Kfsin clay is very low, being on average only 9.99×10-7 m s-1. (2) Soil permeability also varied vertically, with Kfs rising first and declining later down the soil in depth at the four experimental points in the Sishilijing Basin. As the number of soil samples was limited, causes and trend of the change need to be further explored. (3) Analysis of factors affecting Kfs and its mechanism shows that Kfs is closely related to soil physical and chemical properties, and the principal component analysis indicates that Kfs affecting factors may be summarized as follows: the first principal component may be described as soil looseness, which is affected mainly by initial soil water content, organic matter content and soil particle size composition; the second one is basic physical and chemical properties, mainly including soil pH, soil total ion content, soil bulk density and soil particle size (>0.5 mm) composition; and the third one is soil particle size composition, mainly of the particles ranging from 0.1mm to 0.5 mm in size. In a word，among all the affecting factors, the contents of moderate-coarse sands (> 0.5 mm) and clayey silts (< 0.1 mm) are the highest in effect affecting Kfs , while the content of medium-fine sands (0.1 ~ 0.5 mm) is the lowest.
李杰彪,苏 锐,周志超,郭永海,季瑞利,张 明.高放废物处置库预选场址包气带土壤渗透性研究[J].土壤学报,2015,52(6):1412-1421. DOI:10.11766/trxb201412090635 Li Jiebiao, Su Rui, Zhou Zhichao, Guo Yonghai, Ji Ruili, Zhang Ming. Soil permeability of aeration zone in Xinchang-Xiangyangshan - a preselected site for high level radioactive waste disposal[J]. Acta Pedologica Sinica,2015,52(6):1412-1421.复制