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One of Iraq’s most significant groundwater-bearing limestone aquifers is the Dammam Formation. The aquifer groundwater has been studied hydrogeochemically. It is suitable for irrigation, as indicated by sodium adsorption ratio (SAR) and total dissolved solids (TDS), which are 4.15 and 1971 ppm (in average) respectively. Through the vision of the Stiff diagram, the predominant ions are Cl-, SO4 2+ and Na+ while the HCO-3 and Mg2+ are relatively poor. There is plenty of flowing wells in the study area in Najaf Governorate producing groundwater from the Dammam aquifer. In recent years, many wells have been drilled in an irregular pattern for forming fish breeding lakes. These lakes’ water drains 4.715 m3/s into the Najaf depression by Wadi Al- Khur and artificial channels, where it mixes with brine water, rendering it useless. This lead to the exhaustion huge amount of precious groundwater resource. Many signs that confirm the Piezometric pressure drop and groundwater levels descent in the Dammam aquifer in the region. The groundwater flow has been halted in several flowing wells in the study area especially in Wadi Al-Khur due to the exhaustion of the reserve and a decrease in the level of the hydrostatic pressure of the aquifer. A significant decline in values transmissivity and specific capacity of the Dammam aquifer when compared with previous studies in the years 1996 and 2009. Through observation of the monitoring well (W/7), a decrease in groundwater levels of flowing wells in the study area.

Sedimentological properties of the dunes and valley terrigenous sediments in Al-Muthanna Governorate, southern Iraq were carried out. Ten samples were collected, where five samples from both sand dunes, and valley sediments. Grain size analysis revealed that sand, silt and clay fractions are the constituents of these sediments. Sand fractions predominant in the dunes and the texture is classified as silty sand, whereas clay fractions dominate in the valley sediments, with sandy clay texture. The mineralogy is determined by X-ray diffraction, which revealed that quartz is the main mineral in both study areas, followed by calcite, feldspars in lesser amount and evaporates (gypsum) in minor component of the light minerals. Petrographically, monocrystalline quartz dominates over polycrystalline quartz in both areas. Rock fragments in the valley sediments are higher than in the sand dunes, which are comprised of carbonate, chert, igneous, metamorphic, evaporate, and mudstone rock fragments. Feldspars are approximately similar in the study areas and comprised mainly alkali feldspar (potash feldspar) and plagioclase. Petrogenically, the sand dunes occupy the quartzose-recycled field, while the valley sediments fall in transitional recycled fields represented recycled orogeny.

The geophysical method (Cross-Hole Survey) was used to assess the bearing capacity of the soil in the study area to build a water treatment plant. It was noted, that the velocities of the primary and secondary waves decrease at the depths of 4 and 5 meters compared to the depths above and down, so, the lithology or physical properties of this specific soil have changed. It was also observed that seismic wave velocities are low in general due to the medium density and hardness of the soils in the study area. Furthermore, the elasticity modulus values were shown to decrease at depths of 4 and 5 meters. It is further evidence of the soil's weakness at these depths. When the type of layer changed, the elastic modulus changed as well. The geotechnical properties between the wells were evaluated based on the velocities of seismic waves (S-waves and P-waves) for classifying the load capacity values with the stiffness. The bearing capability of the soil was found to be medium-stiff at depths of 2 and 3 meters, but soft at depths of 4 and 5 meters. At depths of 6, 7, 8, 9, and 10 meters, the bearing capacity is stiff to very stiff.