Evaluation of groundwater quality and assessment of scaling potential and corrosiveness of water samples in Kadkan aquifer, Khorasan-e-Razavi Province, Iran

Abstract

The chemical analysis of 129 groundwater samples in the Kadkan area, Khorasan-e-Razavi Province, NE of Iran was evaluated to determine the hydrochemical processes, assessment of groundwater quality for irrigation purposes, corrosiveness, and scaling potential of the groundwater. Accordingly, the suitability of groundwater for irrigation was evaluated based on the sodium adsorption ratio, residual sodium carbonate, sodium percent, salinity hazard, and US Salinity Laboratory hazard diagram. Based on the electrical conductivity and sodium adsorption ratio, the dominant classes are C3-S1, C3-S2, C2-S1, and C4-S2. According to the Wilcox plot, about 50 % of the samples fall in the "Excellent to Good" and "Good to Permissible" classes. Besides, the Langelier saturation index, Ryznar stability index (RSI), Larson-Skold index, and Puckorius scaling index were evaluated for assessing the corrosiveness and scaling potential of the groundwater. Corrosiveness and scaling indices stated that the majority of samples are classified into "Aggressive" and "Very Aggressive" category. In addition, chloride and sulfate interfere in 90 % of the samples. Assessment of hydrochemical characteristics indicates Na-Mg-Cl as the predominant hydrochemical type. Spatial distribution of hydrochemical parameters indicates that hydrochemical processes are influenced by geology and hydrogeology of Kadkan aquifer. The Gibbs plots gave an indication that groundwater chemistry in this area may have acquired the chemistry mainly from evaporation and mineral precipitation. Grouping the samples based on Q-mode hierarchical cluster analysis helped to more separation of similar samples. The R-mode HCA grouped analyzed parameters into two groups based on similarity of hydrochemical characteristics. As a result, the samples collected in northern and southern parts of the study area show the best quality (i.e., lowest salinity) for some purposes such as irrigation and drinking.

Assessment of corrosion and scaling potential of the groundwater in the Thanjavur district using hydrogeochemical analysis and spatial modeling techniques

“…This index represents the corrosive or coating behavior of the groundwater samples. The amount of free CO 2 in excess amount and its chemical behavior with Ca and Mg are the most important causes for the corrosive nature of the water [31,32]. The dynamics of carbonate and the presence of CO 2 are controlled mainly by the pH values of water.…”

An evaluation of the possibility of water chemical quality restoration at the user by filtration through an activated silica bed

“…Water chemical stability is described by saturation, indicator of the aggressiveness (I), Langelier (IL) or Ryzner (IR) indices, which characterize the calcium-carbonate equilibrium [5]. Values of water indicators which define water as corrosive is presented in the table 1.…”

Groundwater Quality Assessment Based on Geographical Information System and Groundwater Quality Index

“…To express the data as the global norm, the concentration measured in each C cell in the initial map was presented as its ideal standard value of Ć (3,5,14). In the resulting maps, the pixel value is between -1 to +1.…”

“…In this regard, monitoring and zoning of water, as important variables, should be considered in planning (3,4). Because of some unique features (compared to surface water resources), the groundwater has been regarded as one of the main resources of water supply in many countries, including Iran (5,6).…”