Soal Jawab Air Bawah Tanah

Kebelakangan ini, ramai individu yang kononnya pakar dalam air bawah tanah bercakap di televisyen dan catatan wawancara mereka disiarkan di akhbar. Kebanyakannya saya dapati bercakap tanpa ilmu. Kalau adapun, ilmu separuh masak! Di bawah ini saya siarkan soal dan jawab bagi soalan-soalan yang selalu menjadi kebimbangan orang ramai terhadap penggunaan air bawah tanah sebagai sumber air minum bersih. Jawapan disediakan oleh kumpulan pakar hidrogeologi dari Sime Darby diketuai Dr Azuhan Mohamed. (Terjemahan sebahagian artikel di bawah disediakan oleh saya sendiri). Mudah-mudahan orang awam non-geologist yang membaca dapat memahami dengan jelas.
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Groundwater is a Sustainable and Reliable Source of Water

25 August 2009- In response to statements made by the Federation of Malaysian Consumer Associations (FOMCA), Sime Darby wishes to state that Groundwater is indeed a sustainable and reliable source of water if abstracted correctly using appropriate methods and technology. This fact has been proven in countries such as Denmark where 100% of water consumed is sourced from groundwater. Sime Darby has invested in state-of-the-art technology and has employed leaders in the industry both at a global and regional levels. There is no question of the ability of our experts (as listed below) and neither is there any question on the technology that is being used to ensure the sustainability and continued viability of our groundwater project.

Groundwater abstraction is undertaken at depths far below the water table ranging from between 100 meters to 300 meters below ground level. (This water table is at depths of only between 30 meters to 50 meters.)

The demand for water in Malaysia is expected to grow significantly by 2010 to approximately 17,000 Mld when the country’s population reaches 30 million. Currently, surface water accounts for more than 98 per cent of water consumed in Malaysia. This is a level of dependence is unsustainable and needs urgently to be addressed, especially since surface water is easily affected by extreme weather conditions, as Malaysians know only too well. This is a matter of grave concern for the whole country and all responsible organisations should be looking into addressing this imbalance in our national water supply.

Groundwater offers a more reliable and sustainable source of water as long as it is abstracted correctly, utilizing appropriate methods and technology.Groundwater is not only an environmentally friendly source as it causes minimal disruption to the land surface area but it is also a sustainable source of water as it can be developed in stages to meet increasing demand.

The methodology is not new and is used in countries with significant agricultural communities such as Denmark. Other countries which use groundwater widely include Germany, Switzerland, England, Australia and the United States among others. It is widely considered a sustainable source of water when recharge rates are taken into consideration and monitored as groundwater is abstracted.

Batang Padang was specifically identified for this pilot project as this area enjoys a high annual rainfall of almost 3,300mm and contains favourable natural fracture & fault lines as well as large areas of undeveloped land and water catchment areas. Furthermore, concerns raised on the salinity and impact on soil stability of the ground are unfounded for the reasons listed below.Sime Darby has communicated these facts to FOMCA and offered a dialogue session to explore the concerns raised several months ago. FOMCA declined to meet with and/or engage with our experts.

Item-By-Item Clarification on Impacts of Groundwater Abstraction As Noted by Fomca

Nos.	Impacts	Clarifications
1	Reduction in river flow and surface water. This includes also wetlands, lakes and springs. (Pengurangan dalam aliran sungai dan air permukaan. Ini termasuk juga tanah bencah, tasik dan mata air.)	Valid in unconfined aquifers and when groundwater abstraction is undertaken close to rivers and other surface water bodies. But the impact due to groundwater abstraction on river flows is negligible compared to surface water abstraction from both direct abstraction from rivers and artificial reservoirs behind dams. (Sah dalam akuifer tak terkurung dan apabila pengekstrakan air bawah tanah dijalankan berhampiran dengan sungai dan badan air permukaan yang lain. Tetapi kesan akibat pengekstrakan air bawah tanah ke atas aliran sungai boleh diabaikan berbanding dengan pengekstrakan air permukaan dari abstraksi secara terus dari sungai dan takungan buatan di empangan.) Invalid for groundwater abstraction from unconfined aquifers away from rivers and other surface water bodies as well as from confined aquifers. (Tidak sah untuk pengekstrakan air bawah tanah dari akuifer tak terkurung jauh dari sungai dan lain-lain badan air permukaan serta dari akuifer terkurung)
2	Living organisms that depend on the availability of groundwater will be affected and slowly killing the ecosystem.(Organisma hidup yang bergantung kepada adanya air bawah tanah akan terjejas dan perlahan-lahan membunuh ekosistem.)	Invalid since under natural conditions, water tables fluctuate that is, water tables are high (close to the ground surface) during wetter months and low during drier months. (Tidak sah kerana di dalam keadaan semula jadi, paras air tanah berubah-ubah iaitu tinggi (dekat dengan permukaan tanah) semasa musim lembap dan rendah semasa musim kering.)
3	Intrusion of sea water through seepage to fresh water area. This will also impacts to swamps and seaside ecosystems. (Perejahan air laut melalui resapan kepada kawasan air tawar. Ini juga akan memberi kesan kepada ekosistem paya dan tepi pantai.)	Valid in coastal unconfined aquifers and when groundwater abstraction is at a rate that reduces freshwater pressure and results in upconing of seawater below the wells. (upconing refers to the rise of the interface between freshwater-saline water that can result in saline water entering the wells) (Sah di akuifer terkurung pinggir pantai dan apabila pengekstrakan air bawah tanah adalah pada kadar yang mengurangkan tekanan air tawar dan menyebabkan upconing air laut di bawah perigi. (upconing merujuk kepada peningkatan antara muka antara air masin-air tawar yang boleh menyebabkan air masin memasuki telaga) Shallow coastal aquifers can be safely developed by controlling the rate of groundwater abstraction and through the use of horizontal wells. (Air dari akuifer cetek pinggir pantai boleh diambil dengan selamat dengan mengawal kadar pengekstrakan air bawah tanah dan melalui pembinaan telaga mendatar.) Groundwater abstraction from coastal confined aquifers is safe and they are many noted discoveries of freshwater springs in the seabed. Offshore drilling for oil also noted the occurrences of freshwater at depths below the seabed. (Pengekstrakan air bawah tanah dari akuifer pinggir pantai yang terhad adalah selamat dan banyak rekod penemuan mata air tawar di dasar laut dicatatkan. Penggerudian luar pesisir bagi petroleum juga banyak merekodkan penemuan air tawar dalam lapisan batuan di bawah dasar laut.)
4	Soil stability will be affected and will cause sinkhole problems. Reduction or extraction of groundwater will cause drop in ‘pore pressure’ for soil stability.(Kestabilan tanah akan terjejas dan akan menyebabkan masalah lubang benam. Pengurangan atau pengekstrakan air bawah tanah akan menyebabkan penurunan dalam 'tekanan liang ' yang penting kestabilan tanah.)	Valid for groundwater abstraction in karstic limestone aquifers and it is associated with high groundwater abstraction and improper well design. (Sah untuk pengekstrakan air bawah tanah dalam akuifer karst/batu kapur dan kejadian ini dikaitkan dengan kadar pengekstrakan air bawah tanah yang tinggi, tidak terkawal dan reka bentuk telaga yang tidak wajar.) There are many cases worldwide that through best groundwater management practices, it is safe to abstract groundwater in karstic limestone aquifers.(Terdapat banyak kes di seluruh dunia khususnya di China di mana melalui amalan terbaik pengurusan air bawah tanah, adalah selamat untuk pengekstrakan air bawah tanah dalam akuifer karst/batu kapur.)
5	Overall, it is not a sustainable activity to be done and it is not environmental friendly.(Secara keseluruhannya, ia merupakan satu aktiviti yang tidak mapan dilakukan dan ia tidak mesra alam.)	Valid under the condition of groundwater over abstraction or undertaken without best groundwater management practices. (Sah dalam keadaan di mana amalan terbaik pengurusan air bawah tanah tidak dilaksanakan.) Best groundwater management practices lead to sustainable groundwater development that benefits both socio-economic development and environment as proven in developed economies. (Amalan terbaik pengurusan air bawah tanah akan membawa kepada pembangunan air bawah tanah yang mapan dan memberi manfaat kepada kedua-dua pembangunan sosio-ekonomi dan persekitaran seperti yang terbukti di negara maju.)
6	Groundwater abstraction affects oil palms and other vegetation. (Pengekstrakan air bawah tanah memberi kesan kepada pokok kelapa sawit dan tumbuh-tumbuhan lain.)	Oil palms and other vegetation do not depend on groundwater for their water intake but on the water that is contained within the unsaturated zone or soil moisture. (Pokok kelapa sawit dan tumbuh-tumbuhan lain tidak bergantung kepada air bawah tanah bagi keperluan air mereka tetapi bergantung kepada air yang terkandung dalam zon tak tepu atau kelembapan tanah.) Vegetation growth depends on rain water and in the absence of rain water, vegetation wilts and dies off. This explains the phenomenon of thick vegetation in rain forests and sparse vegetation in semi-desert or desert areas as well as the need for irrigation to grow crops during dry season or to grow crops in semi-desert or desert areas. In the latter, well irrigation is widely practised. (Tumbesaran tumbuhan bergantung kepada air hujan. Dalam keadaan ketiadaan hujan, tumbuhan menjadi layu dan mati. Ini menjelaskan fenomena keadaan pokok-pokok tumbuh tebal di kawasan hutan hujan, berselerak di kawasan separa padang pasir atau padang pasir. Sistem pengairan perlu untuk tanaman semasa musim kering atau di kawasan separa-gurun atau padang pasir. Di kawasan gurun, pengairan dengan sumber air dari telaga air bawah tanah diamalkan secara meluas.)

Key Personnel In Sime Darby Groundwater Development Activities

Professional	Qualifications/Experiences
Ir. Dr. Azuhan Mohamed Position: Head - Water Management Age: 50 years old Nationality: Malaysian	B.Sc (Hons) – major in Hydrology and Hydraulics Engineering, Univ. of Newcastle upon Tyne, UK M.Sc. in Hydrogeology, Univ. of Birmingham, UK Phd. in Civil Engineering – major in groundwater, Univ. of Birmingham, UK Professional Engineer Corporate Member Institution of Engineers Malaysia Licentiate Institute of Geology Malaysia Certified Groundwater Professional – Association of Groundwater Scientists and Engineers, USA More than 27 years experience in the field of groundwater engineering
Mr. Chong Foo Shin Position: Principal Hydrogeologist Age: 69 years old Nationality: Malaysian	B.Sc. (Hons) Geology, Univ. of New South Wales, Australia Diploma in Hydrogeology, Univ. of London, UK M.Sc. Hydrogeology, Univ. of London, UK Fellow Institute of Geology Malaysia More than 40 years experience in the field of hydrogeology
Mr. Lindsay Furness Position: Principal Hydrogeologist Age: 55 years old Nationality: Australian	M.App.Sc. in Hydrogeology, Univ. of New South Wales, Australia Registered Professional Geoscientists, Australia Consultant to UN agencies and has worked in 16 countries on groundwater related projects More than 32 years experience in the field of hydrogeology
Prof. Dr. Manfred Krieter Position: Advisor Age: 61 years old Nationality: German	Professor of Hydrogeology, Hydrology, Hydrogeochemistry and Soil Sciences, Department of Geosciences, Univ. of Muenster, Germany More than 35 years experience in the field of hydrogeology

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