لخّصلي

purposes.The sources of organic compounds in oxidation ponds and the groundwater of the Pleistocene aquifer are mainly related to human and industrial activities.The most important overall of these compounds are aromatic hydrocarbons (mostly from gasoline, diesel and other fuels as benzene, toluene, ethylbenzene and xylene) and total oil and grease.The volatile organic compounds are detected in the three oxidation ponds with different concentrations, while the groundwater in the area of study is totally free from these compounds with few exceptions (wells Nos. 6, 7, 10, 12, 14 and 15).2.3.

purposes.

E. Organic Compounds Concentration

Human activities have introduced a vast number of synthetic organic compounds into the environment and causing pollution of surface water and groundwater resources. The most important overall of these compounds are aromatic hydrocarbons (mostly from gasoline, diesel and other fuels as benzene, toluene, ethylbenzene and xylene) and total oil and grease. One gallon of gasoline is enough to render one million gallons of groundwater unusable (Noonan and Curtis, 1990). The aromatic hydrocarbons have a number of properties in common: they are volatile, soluble in water and relatively resistant to biodegradation. In the area of study, the results of organic compounds' analyses revealed that:

1. The volatile organic compounds are detected in the three oxidation ponds with different concentrations, while the groundwater in the area of study is totally free from these compounds with few exceptions (wells Nos. 6, 7, 10, 12, 14 and 15). 2. The total oil and grease detected in oxidation ponds with levels more than that detected in the

groundwater. 3. The sources of organic compounds in oxidation ponds and the groundwater of the Pleistocene aquifer are mainly related to human and industrial activities.