Evaluation of the Environmental Impacts of Water Disposal Associated With Crude Oil Production on El-Moghra Aquifer in Abu El-Gharadig Basin, South East Qattara Depression

         Egypt entered the water poverty area where the water per capita amounted to700 m³/year. This is due to the limited water resources compared with the water demands. The physical and chemical properties of the groundwater differ from surface water related to the environment in which it occurs. Groundwater is affected by surface activities, rainwater, seepage, irrigation water and drainage water and other effluents. Shortage of water sources in Egypt bring out the issue of using non-conventional water resources.Industrial activities represent the most hazardous source of ground water pollution and disposal lagoons for water associated with crude oil production represent the main source of pollution to Moghra aquifer in the study area. The large quantities of water drained daily to the un-lined disposal lagoons, facilitate the salt water intrusion to the aquifer layer. There are three main water disposal lagoons in the study area, the surface area of the main lagoons ranges from 0.08 to 2.08 Km² with a total surface area of about 3.28 Km² and the average quantity of water were drained to these lagoons equal 7,155 m³/day, the water accompanied with the oil wells, disposed in open ponds, forms another source recharging the Moghra aquifer in the study area. The Moghra aquifer is steady at -50 m below disposal lagoons there will be a direct hydraulic connection with the aquifer.This fact indicated by the continuous rise of the water level of the Moghra aquifer around and in the vicinity of the disposal lakes. The Moghra aquifer is discharged through few wells inside the concerned area and through many wells outside the concerned area. and a rise in the Moghra aquifer’s water salinity also was seen in the results of water analysis for water wells tapped to Moghra aquifer during time in the study area, Many water samples were collected between 2011 to 2021 from the study area, the TDS contents of groundwater samples collected in 2011 around 22,000 mg/l at wells No. 2, 3 & 5 and TDS start to increase with time to reach 35,000 mg/l in the same wells .Also the water samples were collected from the un-lined disposal lagoons, the TDS contents of these samples 42,000 mg/l. A proper interrelation between the surface water and groundwater systems in the study area is clearly recognized. The present work is a trail to evaluate the groundwater resources potentialities of El-Moghra aquifer in Abu El-Gharadig Basin, South east Qattara Depression to achieve a sustainable development of water in this area. In addition, investigation the possible environmental impacts of these disposal lakes on the groundwater regime of the area.