Residents in Chiang Rai are worried that murky water from the Kok River, which flows from its source in Shan State, Myanmar, through Mae Ai in Chiang Mai and into Chiang Rai over a 130-kilometre stretch, may contain cyanide and mercury.
Chiang Rai’s provincial governor has ordered an environmental inspection amid fears of chemical contamination, including cyanide and mercury, possibly linked to a Chinese-financed gold mine in Mong Yawn, Myanmar.
Chiang Mai’s Environmental and Pollution Control Office Authorities had already collected water samples for testing on March 19. The tests aim to determine the presence of cyanide, a substance commonly associated with gold mining, among other parameters.
Following this, Chiang Rai Governor Charin Thongsuk instructed the Provincial Office of Natural Resources and Environment to work with Chiang Mai officials to conduct further water testing in Chiang Rai on March 24.
The action was prompted by reports and concerns over mining activities near the Kok River in Myanmar, which borders Thailand near Mae Ai.
Locals have voiced their concerns about the river’s water quality, as it is widely used for daily needs in Chiang Rai before eventually meeting the Mekong River near Ban Sop Kok, Chiang Saen district.
The Kok River also connects with important tributaries such as the Lao, Korn, and Mae Suai rivers, amplifying fears of potential contamination affecting broader areas.
Initial inspections conducted on March 19 at Ban Kaeng Sai Moon, Tambon Tha Ton in Mae Ai, found that while the water appeared murky, its overall quality was still within acceptable levels.
Indicators such as oxygen content and acidity (pH) ranged from 7 to 8, which is considered normal. Electrical conductivity tests also showed no anomalies. However, detailed results to confirm the presence of harmful substances, including cyanide, will take another month to finalize.
Some residents in Tha Ton mentioned significant mining activity near Ban Hung, which is under Wa State’s administration and located about 36 kilometres from Thailand’s border.
Reports indicate that over 23 Chinese companies are mining operations along the Kok River in Myanmar, predominantly focused on gold extraction. This has raised further unease regarding potential environmental impacts on the Kok River and surrounding communities.
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Geoff Thomas is an award winning journalist known for his sharp insights and no-nonsense reporting style. Over the years he has worked for Reuters and the Canadian Press covering everything from political scandals to human interest stories. He brings a clear and direct approach to his work.