Hydrochemical Analysis of Groundwater in Coastal Coal Mining Areas—A Case Study of the Liangjia Coal Mine,North China

To understand the hydrochemical characteristics and circulation pattern of groundwater in coastal coal mining areas, we analyzed 81 water samples from different water bodies in the Liangjia coal mine (LCM) area using multivariate statistical analysis and hydrochemical methods. The Quaternary groundwater (QW), accumulated water (AW) in the subsidence area, and mine water (MW) in the LCM all exhibit weakly alkaline to slightly saline water chemistry. The dominant cations and anions in the water are sodium (Na⁺) and chloride (Cl^?), reflecting the influence of seawater intrusion. Some ions in QW, AW, and MW exhibited significant annual variations, but Na⁺ and Cl^? concentrations increased with time. The water samples were divided into four categories through cluster analysis: C1 and C2 (bedrock water samples), C3 (water samples prominently affected by seawater intrusion), and C4 (QW and AW in the surface subsidence area). According to the Piper diagram, QW and AW in the surface subsidence area mainly correspond to the Na?Cl type, whereas the MW mainly consists of Na?Cl and Na?HCO₃ types. Factor analysis revealed four main factors: seawater recharge, HCO₃-rich bedrock water, alkaline water, and Quaternary groundwater (QW) with eigenvalues of 4.18, 2.44, 1.22, and 1.19 respectively, which explained 81.98% of the original data information. The comprehensive results of hydrochemical analysis and mathematical statistics indicated that the recharge sources of MW in LCM include seawater, QW, AW, HCO₃-rich bedrock water, and mixed water. Based on regional hydrogeological conditions, a preliminary groundwater circulation model of the coastal coal mining area was constructed. Groundwater generally flows into the Bohai Sea from southeast to northwest, and coal mining has changed the original local groundwater runoff patterns and intensified seawater intrusion.

     

基于PCA-RA的滨海矿井水源识别技术研究

煤炭开采过程中矿井水害的发生,严重威胁着煤矿的安全生产,确定水源数量和类型对于矿井水害的防治具有重要意义。为了明确滨海煤矿矿井水补给来源的数量和类型,以龙口梁家煤矿为例,对矿区内不同水体(矿井水、第四系水和地表塌陷区积水)分别进行取样,并基于水化学和主成分分析-残差分析(PCA-RA)进行矿井水源识别。结果表明:梁家煤矿区内第四系水、地表塌陷区积水和矿井水中的主要化学组分含量差别较大,且受到了海水入侵作用的影响。就均值而言,矿井水中的阳阴离子质量浓度分别存在着ρ(Na⁺)>ρ(Ca²⁺)>ρ(Mg²⁺)>ρ(K⁺)和ρ(HCO₃^-)>ρ(Cl-)>ρ(SO₄²)>ρ(Cl-)的关系。不同水体中,Cl-和Na+均为优势阴、阳离子,水化学类型以Na-Cl型为主,并且3种水体之间存在着一定的水力联系。选取的水化学数据适合进行PCA,但仅根据特征值大于1或是累计方差贡献率大于85%来确定主成分的数量,并不能很好地表征原始数据的全部信息。基于水化学和PCA-RA方法,确定了梁家煤矿矿井水共有5个补给来源,即海水、富HCO3基岩水、塌陷区积水、混合水和第四系水。PCA-RA法能有效地处理和表征原始水质数据信息,可更加合理地确定矿井水的补给来源类型和数量。研究结果可为滨海煤矿区的水害防治提供科学依据。     

日照市涛雒地区浅层地下水污染源解析

根据日照市涛雒地区16组实测枯、丰两期浅层地下水数据,选取总硬度、TDS,SO_4~(2-),Cl~-,Fe,Mn,挥发性酚类,COD,NO_3~-,NO_2~-,NH_4~+,F,Se,Pb,Be等15项污染影响因子,使用多元统计-因子分析法对研究区内浅层地下水环境进行污染源解析。结果表明:源解析结果基本和实际污染源相一致,因子分析法对涛雒地区地下水污染进行源解析是可行的;涛雒地区主要存在4种污染特征源,它们分别是海水入侵源、冶炼源、化工源、农业生活源,对浅层地下水的污染贡献率分别为38.37%,18.49%,12.05%,11.23%。研究结果可为涛雒地区的地下水环境污染的进一步改善和治理提供参考。     

河西走廊浅层地下水主离子特征及水质评价

为查明河西走廊浅层地下水的主离子特征及浅层地下水水质状况,运用数理统计法、Piper三线图、相关性分析、Gibbs图及离子比例系数等手段,对研究区75个水样点的水化学指标进行了全面研究。在此基础上,采用了模糊综合评价法与内梅罗指数法对该地区浅层地下水进行了水质评价。结果表明:河西走廊浅层地下水整体偏碱性;Cl~-、Na~+、K~+、NO~-_3和SO_4~(2-)在空间上存在较强的变异性;水化学类型整体上为重碳酸硫酸型水;研究区内浅层地下水中的Na~+、SO_4~(2-)和Cl~-很可能有相同的来源;水化学组分主要受蒸发-结晶作用,硅酸盐矿物、蒸发岩盐及硫酸盐溶解的控制。水质评价结果表明人类聚集地浅层地下水水质较差。