This study was conducted to assess the suitability of groundwater resources for drinking and irrigating purposes in Hamedan–Bahar Plain, west of Iran as a major agricultural district, in the spring and summer of 2018. In so doing, a total of 60 water specimens were collected from the semi-deep water wells of the study area with an average depth of 50–75 m and then the hydrogeochemical characteristics of groundwater samples and their suitability were investigated. The evaluation of the groundwater quality was carried out by assessing the physicochemical variables notably temperature (T), pH, electrical conductivity (EC), total dissolved solids (TDS), total hardness (TH), and by measuring the rates of major ions including Ca²⁺, Cl⁻, HCO₃⁻, K⁺, Mg²⁺, Na⁺, NO₃⁻, PO₄³⁻, and SO₄²⁻ and trace elements, such as arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn). The results indicated that the groundwater specimens were somewhat alkaline and brackish. The cationic trend of the specimens in the spring season was found to be Ca > Mg > Na > K > Pb > As > Cu > Zn > Ni > Fe > Cr > Mn > Cd, while, in the summer season it manifested itself as Ca > Mg > Na > As > K > Pb > Cu > Zn > Fe > Ni > Cr > Mn > Cd. However, the trend of anionic contents in both seasons was HCO₃ > NO₃ > SO₄ > Cl > PO₄. The analysis of the data showed that Na–Cl–HCO₃ was the dominant groundwater type in both seasons. The studied specimens were also described in terms of some indices, including the total hardness (TH), Kelley’s ratio (KR), magnesium hazard (MH), permeability index (PI), the residual sodium carbonate (RSC), sodium adsorption ratio (SAR), soluble sodium percentage (SSP), and maximum permissible limit (MPL). The results indicated that groundwater samples have suitable quality for the main uses. Based on the values obtained for chloro-alkaline indices (CAI-1 and CAI-2), chemical weathering was suggested as the main hydrogeochemical process controlling calcium, magnesium, sulfate, and carbonate distribution in the groundwater supplies.

这项研究的目的是评估2018年春季和夏季在伊朗西部作为主要农业区的Hamedan–Bahar Plain的地下水资源是否适合饮用和灌溉。在此过程中，共采集了60个水样从研究区域的半深水井收集平均深度为50-75 m的水，然后研究地下水样品的水文地球化学特征及其适用性。评估地下水质量的方法是评估物理化学变量，特别是温度（T），pH值，电导率（EC），总溶解固体（TDS），总硬度（TH）以及测量主要离子的比率，包括的Ca ²⁺，氯^-，HCO ₃^-，K ⁺，Mg的²⁺，钠⁺，NO ₃ ^-，PO ₄ ^3-和SO _4种^2-和微量元素，如砷（As），镉（Cd），铬（Cr），铜（Cu ），铁（Fe），锰（Mn），镍（Ni），铅（Pb）和锌（Zn）。结果表明，地下水标本有些碱性和微咸。春季样品的阳离子趋势为：Ca> Mg> Na> K> Pb> As> Cu> Zn> Ni> Fe> Cr> Mn> Cd，而在夏季，其表现为Ca> Mg> Na> As> K> Pb> Cu> Zn> Fe> Ni> Cr> Mn> Cd 然而，₃  > SO ₄  > Cl> PO ₄。数据分析表明，Na–Cl–HCO ₃是两个季节中主要的地下水类型。还根据一些指标描述了所研究的试样，包括总硬度（TH），凯利比（KR），镁危害（MH），渗透性指数（PI），残余碳酸钠（RSC），钠吸附率（ SAR），可溶性钠百分比（SSP）和最大允许限值（MPL）。结果表明，地下水样品具有适合主要用途的质量。根据获得的氯碱指数（CAI-1和CAI-2）值，建议化学风化是控制地下水供应中钙，镁，硫酸盐和碳酸盐分布的主要水文地球化学过程。