Chiang Rai, August 22, 2025 — Thailand’s Geo-Informatics and Space Technology Development Agency (GISTDA) has reported findings from satellite monitoring of environmental impacts along the Kok and Sai rivers linked to suspected transboundary mining pollution from Myanmar. The monitoring was conducted under the directive of a subcommittee on surface water quality, chaired by Deputy Prime Minister and Minister of Digital Economy and Society, Prasert Jantararuangtong.
GISTDA deployed high-resolution satellite data, including imagery from THEOS-2 with 50-centimeter resolution, to analyze past and recent land disturbances and mining-related activities. The study covered areas from the Thai border up to the headwaters of the Kok River in Kengtung, and the Sai River in Tachileik, Myanmar.
The analysis identified 60 disturbed sites potentially linked to mining, covering about 4,435 rai (approximately 707 hectares). Of these, 21 sites—spanning 1,771 rai—were newly active in 2025.
Focusing on the two rivers, GISTDA reported that along the Kok River, six sites were identified in 2025 alone, covering 232 rai. In the Sai River basin, 15 new sites emerged, spanning 1,539 rai.
The high-resolution images have been forwarded to Thailand’s Department of Primary Industries and Mines for further verification. Officials will assess whether all 60 locations are active mining sites based on indicators such as the scale of land clearing, visible ore stockpiles, and associated mining infrastructure.
From initial assessment, GISTDA confirmed at least five active mining sites near the headwaters of the Kok River, covering 120 rai, and 27 active sites near the headwaters of the Sai River, covering 3,715 rai. Other locations remain inconclusive, as some show signs of construction or land preparation unrelated to mining. Data limitations, including cloud cover in satellite images, also affected clarity in certain areas.
The retrospective analysis suggests that most of the Sai River mines began operating about three years ago, with some directly in the river channel. Mining along the Kok River is more recent, beginning only 1–2 years ago, and currently less extensive compared to the Sai River basin.
This is a translation of original Thai-language news article https://transbordernews.in.th/home/?p=43629
