Jawdat Abdul Jalil M.Zaki Al-Hamdani a, Habil Border J. Merkelb, Salih Muhammad Awadh c, and Ommer Sabah Ibrahim d.
b Department of Hydrogeology, Institute for Geology, TU Bergakademie Freiberg, Freiberg, Germany
c Department of Geology, College of Science, University of Baghdad
d Kirkuk University, College of Science, Environmental Research Unit
a General Commission for Groundwater, Ministry of Water Resources
Shallow alluvial aquifer found beneath the urban area of kirkuk city. The ancient part of the city (Shorja) is affected by seepage from a local agricultural area making groundwater heavy metals relativity high. This site selected depending on the highest TDS value (3856 mg/L) associated with the highest heavy metal concentrations (Pb, Ni, Co and Zn) in groundwater. The objective of this study is to evaluate the effectivity of natural attenuation for long-term protection of groundwater quality using realistic three-dimensional reactive-transport groundwater model.
The requirements of model for heavy metals in groundwater and the parameter of 3-dimensional reactive transport model were obtained from field investigations and laboratory works, in addition to subsurface stratigraphy, aquifer mineralogy, and hydrochemistry. The simulations were performed by using PHAST program, which is based on the HST3D flow and transport code and the hydrochemical PHREEQC code. The modeling results stressed the applicability of natural attenuation in reducing the concentration of various hazardous metals, where Long-term (20 year) simulation results indicate that heavy metal adsorption on hydrous ferric oxide, effectively capture the movement of heavy metals in groundwater down gradient of source areas, resulting in an basically immobile groundwater plume.
Keywords: Groundwater; Reactive transport modeling; Heavy metals; Attenuation; PHREEQC; PHAST