The Industry Ministry and local agencies in Tak have jointly inspected the readiness of disposal pits before cadmium tailings are relocated there from Samut Sakhon.
Nattapol Rangsitpol, permanent secretary for industry, on Monday said he met Tak governor Somchai Kitcharoenrungroj to discuss the province's preparedness before the cadmium tailings are transported to their point of origin.
He said the ministry cooperated with various local agencies to check the sturdiness of the disposal pits, including the cement structure and drainage system, as stipulated in an environmental impact assessment.
Machinery will also be inspected before the bags containing cadmium tailings are moved to the pits. The surrounding environment will also be assessed for safety purposes.
The province has also invoked Section 29 of the Public Disaster Prevention and Mitigation Act to restrict movement in and out of the factory area within a 100-metre radius of the seven disposal pit sites and the warehouse for 90 days from Monday.
Mr Nattapol has also worked with Bangkok governor Chadchart Sittipunt to inspect suspect factories across the capital.
He will do likewise with the Industrial Works Department and provincial industry office to inspect suspect factories in provinces.
He said no further reports had come to light of more cadmium tailings being discovered.
The current amount of discovered tailings remains at 12,535 tonnes, he said.
The burial site of the tailings is located in tambon Nong Bua Tai of Muang district, less than one km away from Ping River.
More than 1,000 households are situated in the site's proximity.
Residents have opposed the relocation of the tailings back to the area due to concerns about their health and environmental impact.
Karit Pannaim, Move Forward Party MP for Tak, said villagers urged the government to carry out health checks of all people in nearby communities before the relocation.
Meanwhile, the Provincial Waterworks Authority (PWA) on Monday said water samples tested from Tak, Samut Sakhon, and Chon Buri confirmed the water was not contaminated with cadmium and was usable.
The PWA has beefed up its water quality surveillance by regularly testing the water supply from its 234 water production branches.