Geochemical Modeling of Groundwater in AL Teeb Area (North East Missan Governorate)

Abstract

Geochemical model is developed to simulate the geochemical reaction with flow direction of AL Teeb area NE of Missan Governorate, south of Iraq. Geochemical model under geochemical codes, NETPATH and WATEQ4F program is used to develop a groundwater Geochemical model to interpretation of geochemical reaction. According to the conceptual model of the study area, the aquifers system within the area is subdivided into three aquifers: Quaternary deposits (unconfined aquifer), Bai Hassan (semi-confined aquifer), and Mukdadiyah (confined aquifer). Results of pumping test; by applying AQTESOLV Professional version 4.50 for pumping test analysis to determine transmissivity (T), hydraulic conductivity (K.) for wells are distributed of all the studied area, The (T) value ranges from (28.17 - 613.17) m2/day and the (K)value ranges from (1.3 -12 )m/day. The groundwater quality is assessed through the analysis of the Physicochemical parameters such as pH, EC, TDS and major ions (Ca2+, Mg2+, Na+, K+, HCO−3, CI−, SO4−2), nutrients (NO3−).Two generalized flow paths were selected for the study area. These flow paths begin near the Iraq – Iran boundary to the middle of the study area from northeast to the southwest. The detailed results of the ionic strength calculations for and mineral saturation indices. All samples in the selected flow path are under saturated concerning Pco2. The concentrations of calcium, magnesium, Bicarbonate, and sulfate increase along groundwater flow paths. All waters sampled are oversaturated concerning pure stoichiometric calcite. The SI tells us about the mineral is, in fact, present and is dissolving (SI < 0), or is, in fact, precipitating (SI > 0. The primary goal of the mass balance modeling is to define the net mass of minerals dissolved or precipitated along the flow path down gradient. There are two main flow paths reaction indicate system state for different phases CALCITE, DOLOMITE, GYPSUM, ARAGONITE, DIOPSIDE, and NaCl. The flow path 1 between wells (WS-12 and WS-23) and it is representing the lower aquifer in the study area. Where model NETPATH code checked (35) models and four models are compatible with the found concentrations of the chemical elements and selected phases of this reaction. The flow path between wells (WS-4 and WS-18) and it is representing the upper aquifer in the study area, where model NETPATH code checked (15) models and Four models are compatible with the found concentrations of the chemical elements and selected phases of this interaction reaction.