The east foothill of the Taihang Mountains, Hebei Province, is an important groundwater recharge and transport area in the North China Plain. It is of practical significance to study the groundwater hydrochemical characteristics of this area for rational groundwater regulation. In this study, the Chadha rectangular diagram and Piper trilinear diagram were adopted to identify the relevant hydrochemical processes, and the main groundwater hydrochemical type was the HCO₃·SO₄–Ca. Descriptive statistical methods, correlation analysis, major ion ratio determination and principal component analysis (PCA) were employed to analyze the formation mechanism of groundwater hydrogeochemical characteristics and to identify the sources of the main groundwater ions in the study area. The results showed that Ca²⁺ and HCO₃⁻ were the dominant groundwater cation and anion, respectively, and the Gibbs diagram demonstrated that the majority of groundwater samples occurred in the rock weathering-dominated area. Bivariate diagrams revealed that mineral dissolution and ion exchange controlled the groundwater geochemistry. The study area was seriously polluted by NO₃^–, which might be due to the application of farmland fertilizers and leakage of rural domestic sewage and garbage. PCA yielded three principal components (PCs), which represented processes influenced by salinity, human activity and fluoride impacts on the groundwater chemistry. The distribution of high-positive PC scores verified the influences of the various processes on the groundwater study area, which is an effective tool to formulate and implement management strategies for the sustainable development of groundwater areas.

河北省太行山东麓是华北平原重要的地下水补给和运输区。研究该地区的地下水水化学特征，对合理的地下水调控具有重要的现实意义。本研究采用Chadha矩形图和Piper三线性图确定相关的水化学过程，主要的地下水水化学类型为HCO ₃ ·SO _4。–Ca。采用描述性统计方法，相关分析，主离子比确定和主成分分析（PCA）来分析地下水水文地球化学特征的形成机理，并确定研究区域主要地下水离子的来源。结果表明，钙²⁺和HCO ₃ ^-为优势地下水阳离子和阴离子，分别和吉布斯图表明，大多数地下水样发生在岩石风化为主的区域。双变量图显示矿物溶解和离子交换控制着地下水的地球化学。研究区域被NO ₃严重污染^–，这可能是由于农田肥料的使用以及农村生活污水和垃圾的泄漏所致。PCA产生三个主要成分（PCs），它们代表受盐度，人类活动和氟化物对地下水化学影响的过程。高PC分数的分布证实了各种过程对地下水研究区的影响，这是制定和实施地下水可持续发展管理策略的有效工具。