HOW TO DETERMINE GROUNDWATER WELL PRODUCTIVITY
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1 - GEOPHYSICAL STUDY
Electrical resistivity studies will be conducted. This geophysical study will be carried out in the premises area before drilling to ensure sufficient and quality groundwater resources are available (not saltwater). Most areas in Malaysia, such as Shah Alam, Bangi, Klang, and Petaling Jaya, are known for their productivity.
2 - PRELIMINARY STUDY
This study involves a site visit to assess the geological characteristics of the area and to collect data from existing reports and studies.
PHOTO SHOWS PRELIMINARY STUDY IDENTIFYING SOIL/ROCK TYPES IN THE AREA AND GROUNDWATER QUALITY BASED ON IN-SITU SAMPLES OR EXISTING DATA
3 - AIR LIFT TEST AND PUMPING TEST
Initial studies are conducted, and if the premises show potential for groundwater production, you will be notified. Drilling will only commence with your permission.
While drilling is in progress, an 'Air Lift' test is conducted at a specific depth to estimate the groundwater discharge rate. This test is typically performed in areas with high groundwater potential and serves as a guide to determine whether drilling should continue.
AIR LIFT TEST IS UNDERWAY
In cases where preliminary studies and drilling have been completed, but no water source is found (lack of potential), a mandatory payment covering mobilization costs is required. Typically, if the discharge rate is high, drilling will continue until the 'Air Lift' test results show a groundwater discharge value that exceeds the actual need.
PUMPING TEST IN PROGRESS
4. DRILLING WORK
The drilling work will be carried out using a drilling machine. The well drilling process is explained below.
The rotary drilling method is used, inserting a temporary casing with a diameter of 8 to 12 inches into the soft soil layer. When rock or broken rock is encountered, the drilling method changes to using a down-hole hammer.
During drilling, samples of rock, soil, and water are collected and analyzed. The type of soil/rock lithology is recorded in the Drilling Work Report.
DRILLING WORKS IN PROGRESS
DURING DRILLING, SOIL AND ROCK SAMPLES ARE COLLECTED FOR IDENTIFICATION
5. GROUNDWATER QUANTITY TESTING IN THE FIELD
The drilling work report contains information such as the main properties of the rock, the depth, and thickness of the rock fracture area, which is a potential area for groundwater resources. The Drilling Work Report also contains information such as the depth at which the ‘Air Lift’ test was conducted.
The drill log also contains information such as the pumping/discharge rate, and the value of this discharge rate will increase with reference to the depth level. Drilling will stop when the discharge rate value exceeds the requirement. Next, the discharge test is carried out, and a more accurate groundwater discharge rate will be known. Additionally, the depth of the static groundwater level is also recorded.
DISCHARGE TESTS ARE CONDUCTED TO DETERMINE SAFE WATER DISCHARGE RATE
FIELD WATER QUALITY TESTS ARE CONDUCTED TO ASSESS WATER SALIENCY AND TURBIDITY
After the drilling and discharge test work is completed, the PVC screen will be inserted into the temporary casing. The diameter, screen slot size, and screen depth need to be determined first.
The external structure for the well will then be completed. A high-capacity submersible pump will be placed in the well. A layer of sand (filter media) will be placed in the empty space between the screen and the borehole to act as a filter for impurities. Next, the internal development work of the well (well washing) will be carried out. Water samples will be analyzed, and the process of preparing the switchboard and installing pipes to the industrial balance tank will follow.
ESTIMATED WORK SEQUENCE AND DRILLING DURATION
You can directly contact +6011 1565 4475 if you have any specific questions or email directly to admin@rbikonsult.com
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