April-June, 2020
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Hydrogeochemical Study for sustainable development in Wadi El-Mathula, East
Qift city, Eastern Desert, Egypt
Saad A. Mohallel
ABSTRACT: Wadi El-Mathula is one of the promising basins in Upper Egypt. Rain fall, River Nile and return
irrigation water represent the main recharging sources for groundwater aquifers in particular
Quaternary water bearing. The hydrogeological data of the main aquifers, namely Quaternary and
Nubian sandstone water bearing formations were discussed. The Quaternary aquifer occupying delta
of Wadi El-Mathula, where it represented by 18 samples has a salinity ranges from fresh (6% of
samples) to brackish water (55%) then saline water (39%) showing an increase due east towards the
new reclaimed and desert lands, where the values vary from 1320 mg/l to 10622 mg/l with mean
value 5381 mg/l. In the Nubian sandstone aquifer (represented by 6 samples) all the groundwater
samples are brackish water where the salinity ranges from 1836 to 2682 mg/l with a mean value of
2072 mg/l. Chloride – Sodium water type is considered the main water type where it characterized the
majority (67%) of the Quaternary groundwater samples and the majority of Nubian groundwater
samples (83%). Calcite and Dolomite dissolution beside the dissolution of halite are the main
hydrochemical processes affecting groundwater quality. The chemical types and hypothetical salts as
well as the ion ratios indicate meteoric origin for groundwater and dissolution of terrestrial salts.
Hydrogeochemical model (PHREEQC 2.8) was used to calculate saturation indices of minerals to the
Quaternary and the Nubian sandstone aquifers. The results indicated that the groundwater in the two
aquifers is undersaturated with respect to Gypsum and Anhydrite indicating the capacity of
groundwater for more mineral dissolution. All samples of the Nubian sandstone and the most samples
of the Quaternary groundwater are supersaturated with reference to Calcite, Aragonite and Dolomite.
The results of the environmental stable isotopes indicated that the groundwater in study area is
discriminated into two distinctive groups. Group (I) belonging to the deep flowing well in Laqita area
(Nubian aquifer) and group (II) of samples is enriched in their isotopic compositions (Quaternary
aquifer). The investigated groundwater is not suitable for drinking purposes. Only 28% of the
Quaternary groundwater samples are considered very satisfactory for all classes of livestock and
poultry. On the other hand, all the groundwater samples of the Nubian sandstone aquifer are
considered very satisfactory for all classes of livestock and poultry. About 5% of the Quaternary
groundwater samples are Intermediate quality for irrigation. In addition the majority of the Nubian
sandstone groundwater samples (67%) are moderate water quality for irrigation and 17% of the
groundwater samples in the same aquifer are Intermediate quality
[ FULL TEXT PDF 60-82 ] DOI: 10.36632/ije/2020.9.2.5
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