The Bangkok Metropolitan Administration (BMA) has warned people not to smoke near drains along a section of Rama III Road because it could ignite an oil leak and cause an explosion.
The City Hall and Pollution Control Department warning applies to an 85-metre-long section of Rama III Road where Klong Toey and Yannawa districts adjoin.
It followed public complaints about a strong oil smell. Workers subsequently found signs of an oil leak at ten drainage system manholes along the road.
Checks on Monday night found volatile organic compounds (VOCs) at concentrations of 350 parts per million, which posed a risk of explosion or fire.
Surin Worakijthamrong, director-general of the Pollution Control Department, said workers sprayed foam to reduce the VOC concentration and would pump the leaked oil from the area.
‘We will pump the oil and move it from the area carefully and will assess risk and safety regularly,’ he said.
The Klong Toey district office said oil absorbent booms were installed to contain the oil and workers sprayed environmentally friendly substances to reduce the smell. The situation would be closely monitored to minimise environmental impact.
Neither the Pollution Control Department nor City Hall explained where the oil leaked from.
Bangkok Governor Chadchart Sittipunt said on Tuesday that 5,000 litres of oil-contaminated wastewater had been pumped out of the drains.
According to the governor, leaked oil and its smell remained, and City Hall workers blocked the local drainage network within a radius of 50 metres to prevent contaminated water from reaching public water sources.
He ordered the Klong Toey district chief to quickly find the source of the oil leak and determine whether the incident resulted from illegal oil disposal or a leak from a pipeline near the drains.
‘An oil storage yard stood in this area… There isn’t a data centre,’ Mr Chadchart added.