Sains Malaysiana 52(8)(2023): 2267-2286

http://doi.org/10.17576/jsm-2023-5208-08

Exploring Strategies Post- Revocation of Licensing Exemption for Malaysia's Tailing Processing Industry

(Meneroka Strategi Selepas Pembatalan Pengecualian Pelesenan untuk Industri Pemprosesan Amang Malaysia)

MUHAMMAD ABDULLAH RAHMAT¹, AZNAN FAZLI ISMAIL^1,2,*, ELI SYAFIQAH AZIMAN ¹, NURSYAMIMI DIYANA RODZI^1, RATNA SUFFHIYANNI OMAR^1,2, WAN MOHD RAZI IDRIS^3,4 & TUKIMAT LIHAN⁴

¹Nuclear Science Programme, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

²Nuclear Technology Research Centre, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

³Water Analysis Research Centre (ALIR), Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

⁴Department of Earth Sciences and Environment, Faculty of Science and Technology,

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

Received: 12 April 2023/Accepted: 18 July 2023

Abstract

The extraction of heavy metals and rare-earth elements from tailing residue has caused a significant impact towards the environment as well as the industrial workers as a result from the contamination caused by the processing activities. The radionclide concentration of ²²⁶Ra, ²³²Th, and ⁴⁰K in soil and tailing residue were found to be within the range of 0.31 - 4.97 Bqg^-1 and 1.24 - 4.47 Bqg^-1, 0.16 - 11.07 Bqg^-1 and 1.08 - 8.56 Bqg^-1, 0.22 - 1.24 and 0.18 - 1.32 Bqg^-1, respectively. The radiological impack assessment findings indicated significant overexposure risks where the annual effective dose was estimated to be within the range of  0.7 – 207.6 mSvy^-1 while the excess lifetime cancer risks we found to have exceeded the limit let by the local regulatory body. The correlation between study findings and the enactment of the licensing exemption order was done to identify the effects of non-regulatory compliance to the Atomic Energy Licensing Act. The study also emphasized on the remediation importance of industrial sites before implementing any form of changes towards new regulatory adherence. Hence, the study recommeneds potential remediation techniques but taking into account the operational status of each proceesing plant, degree of contation and possible future use of the contaminated site.

Keywords: Legislative improvement; NORM; Radiological Impact Assessment; tailing processing; waste management

Abstrak

Pengekstrakan logam berat dan nadir bumi daripada sisa amang telah memberi impak yang ketara terhadap alam sekitar dan juga pekerja industri akibat pencemaran yang berlaku di lokasi yang melibatkan aktiviti pemprosesan. Kandungan kepekatan radionuklid ²²⁶Ra, ²³²Th dan ⁴⁰K dalam tanah dan sisa amang masing-masing berada dalam julat antara 0.31 - 4.97 Bqg^-1 dan 1.24 - 4.47 Bqg^-1, 0.16 - 11.07 Bqg^-1 dan 1.08 - 8.56 Bqg^-1, 0.22 - 1.24 dan 0.18 - 1.32 Bqg^-1. Hasil penilaian impak radiologi menunjukkan risiko pendedahan berlebihan yang ketara dengan nilai dos berkesan tahunan berada dalam julat 0.7 - 207.6 mSvthn^-1serta risiko kanser sepanjang hayat didapati melebihi had yang ditetapkan oleh pihak berkuasa tempatan. Hasil kajian ini seterusnya dikaitkan dengan perintah pengecualian pelesenan bagi mengenal pasti kesan akibat ketidakpatuhan terhadap Akta Perlesenan Tenaga Atom. Kajian turut menekankan kepentingan tindakan pemulihan kawasan industri sebelum membuat sebarang perubahan bagi mematuhi akta perlesenan yang baharu. Oleh itu, kajian ini mencadangkan langkah pemulihan dengan mengambil kira status pengoperasian setiap kilang, tahap pencemaran dan juga kebarangkalian penggunaan semula kawasan tercemar.

Kata kunci: NORM; pemprosesan amang; penambahbaikan undang-undang;  pengawalan sisa; Penilaian Impak Radiologi

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*Corresponding author; email: aznan@ukm.edu.my