Using GIS to Find Suitable land for Agriculture in Dhahirah Region in Order to Use the Groundwater of the PDO Wells Associated with Hydrocarbons as an Alternative Method to the injection into shallow aquifers

By
Dr. William Bajjali
Hydrogeologist & GIS Expert

Can the PDO save the environment and keep the groundwater clean for future generation?

Can the PDO contribute in changing the climate by transferring vast area of the desert to a land forest?

Brief Introduction:

PDO produces almost 164 MCM per year of groundwater as an associated co-product of around 49 MCM per year oil. Roughly 65 MCM of the produced groundwater is used by PDO for reservoir pressure maintenance by injection. The rest of the groundwater (~ 100 MCM) is disposed into shallow and deep reservoirs. A quantity of 1000 m3/day is disposed into the marine environment at Mina al Fahl. A smal amount of oil just about 0.014 MCM/year remains in the disposal stream.

Because the oil density (0.86 – 0.97) is less than the water density the oil movement and behavior is consider as LNAPL. This type of oil is always floating at the top of any water body.

This study is come to propose way to avoid dispose the produced water into shallow reservoirs and suggest using the water for producing an ideal farm in Dahiryieh region.

The majority of the groundwater in the PDO wells is highly saline, especially the wells tapping the deep aquifer. This type of water could be used by PDO reservoir pressure by injection and the less saline for irrigation purposes. The less saline water should first at all treated to a level to reduce the hydrocarbon, trace element and salinity to a level that could be used for irrigating plants and trees highly tolerant for salinity. In Dahiryieh area there are 4 treatment plants that could be used to produce good quality water and then plendid with more saline water for this purpose. This is multidisciplinary research that should combine various researchers dealing with soil, water, petroleum chemist and hydrogeologist to classify the hydrochemistry of the groundwater in term of water rock interaction.

This study will be carried out in GIS system in order to integrate all the database associated with this subject. In addition it will be used as complete training for professionals at the Ministry of Water Resources in order to achieve the following:

1. Improve the skills of the Omani professionals in using an advance GIS technology in water resources studies, groundwater quality, and management.

2. Present real water resources and environmental problem dealing with saline water associated with hydrocarbon.

3. Find ways and methods do deal with such an important environmental problem and propose efficient proposals and solutions for it.

Encourage the Omani professionals to carry out research dealing with water resources and environment. Emphasis that at the MWR and other local institutions there are quality and quantity of the database available that will facilitate carrying various type of researches and studies.
The figure below shows the best location to dispose the groundwater associated with hydrocarbon