The
Malaysian Journal of Analytical Sciences Vol 11 No 1 (2007): 237 – 245
SURFACE RADIATION DOSE MEASUREMENT AND MAPPING
OF JENGKA 15 OIL PALM LAND
Zaini Hamzah*1, Masitah Alias 2,
Ahmad Saat1, Abdul Khalik Wood3 and Zakaria Tajuddin 1
1Faculty of Applied Sciences, Universiti Teknologi
MARA,
40450 Shah Alam,
Selangor
2Water and Air Laboratory, TNB Research Sdn. Bhd.
43000 Bangi, Selangor
3Malaysian Institute for Nuclear and Technology
Research,
43000 Bangi,
Selangor
*Corresponding
author: drzainihamzah@yahoo.com
Abstra ct
Measurement
of surface radiation dose will give an indication of how strong the radiation
originating from the soil. The measurement value is related to the
concentration of uranium and thorium in the soil. In this study, oil palm
plantation area in Jengka 15 was chosen as a study area, since it has a
variation in the surface conditions of the land i.e. slopes, flat and
catchments area. Furthermore, it is close to the forest reserved area, which
has been used as a control area. The soil samples were taken using hand auger
up to 20 cm depth. The surface dose
rate measurements were done in-situ using portable radiation survey meter
Ludlum model 2241. The uranium and thorium concentrations were analyzed by
neutron activation analysis technique using the Malaysian Institute for Nuclear
Technology Research (MINT) facilities. The mean value for surface dose rates
were 0.132, 0.122, 0.125, 0.140, 0.123 and 0.160 Sv/hr for flat area 1, flat
area 2, slope area 1, slope area 2, catchments and forest area respectively.
The mean uranium concentrations are 3.0 ± 0.2, 2.0 ± 0.2, 2.0 ± 0.2, 2.0 ± 0.2,
3.1 ± 0.2, and 2.6 ± 0.2 µg/g for flat area 1, flat area 2, slope 1, slope 2,
catchments and forest area
respectively. The mean thorium concentrations are 7.7 ± 0.3, 6.9 ± 0.2, 3.9 ±
0.01, 4.3 ± 0.2, 11.4 ± 0.4 and 7.7 ± 0.0.2 µg/g for flat area 1, flat area 2,
slope 1, slope 2, catchments and forest area respectively.
Keywords : Isodose,
surface dose rate, soil, neutron activation analysis
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