More than 10,000 rai of agricultural land located near a potash mine in Nakhon Ratchasima has been contaminated with sodium chloride and potassium chloride, according to an analysis by the Synchrotron Light Research Institute (SLRI).
The mine was operated by Thai Kali Co, which holds a 25-year concession that expires in 2040.
The concession covers about 9,000 rai of land across the tambons of Nong Bua Takiat, Nong Sai, and Non Muang Pattana in Dan Khun Thot district.
In June, about 150 farmers staged a protest saying their farms had been affected by wastewater discharged from the mine.
They said this has contaminated the area's natural water sources and made the area's soil too salty for the cultivation and production of rice and other key crops.
Villagers petitioned Governor Sayam Sirimongkol on June 27, demanding the closure of the mine.
The protest prompted a halt of mining operations at the site, pending an inspection by state agencies.
The director of the Office of Environment and Pollution Control 11 (OEPC11), Thanachai Wansuk, said on Wednesday the soil samples they sent to the SLRI showed excessive amounts of sodium chloride and potassium chloride.
The results of the analysis will be sent to the governor, who will form a working team to calculate the damage done to the area's farmlands in order that fair compensation can be worked out, Mr Thananchai said.
Supakorn Rakmai, director of the SLRI's light transport utilisation and operation department, said that in addition to excessive sodium chloride and potassium chloride, the SLRI found trace amounts of heavy metals.