If operators could not curb toxic emissions, the area would be made a special zone subject to special control measures. New factories would not be allowed until the pollution was cut to required levels, Kosit Panpiemras said.

The minister spoke after meeting with the Industrial Estate Authority of Thailand (IEAT), which proposed an action plan to the ministry.

IEAT suggested factories should be made to close their chimneys and install equipment to control pollution and prevent hazardous substances being leaked or discharged.

The authorities would monitor 10 factories, including power plants, which discharge nitrogen dioxide. It was found that four power plants in Map Ta Phut including BLCP Power, Glow SPP 3 and PTT discharged 69 per cent of nitrogen dioxide.

IEAT governor Uthai Junthima said apart from factories inside Map Ta Phut, the authorities also closely monitored the situation at IRPC, which is located nearby. The IRPC compound has 28 factories including power plants and oil refineries.

On Friday, IEAT will meet residents from 25 nearby communities to hear their views and clear up some local concerns. Reports about serious pollution have worried people living in the area.

Meanwhile, the Energy Ministry will this week meet private companies that operate industrial plants in Map Ta Phut Industrial Estate to get information on their actual toxic emissions. The information will help the ministry find out solutions to deal with possible expansion. Some 7-8 proposed plants are waiting for environmental impact assessments on construction in the estate.

"Theoretically, plants at Map Ta Phut must reduce toxic emissions or at least not release more toxic substances than now. New plants cannot be built if existing plants do not reduce their emissions," Energy permanent secretary Pornchai Rujiprapha said.

The new plants, mostly in power business, want to be located in the estate's "hot spot" to facilitate an exchange of raw materials with existing plants.

The ministry wants to know about actual emissions from existing plants as well as the list of toxic substances being released. The information should lead to guidelines to control toxic substances exchange by old and new plants, to control emissions.

Industrial plants emitting toxic substances over set limits would be the first forced to make cuts. Others would then have to install equipment to reduce toxic substances, probably through joint investment with new plants.

"The exchanges are necessary as the plants compliment each other. They should be located at nearby sites, but first, they would need to help cooperate to reduce pollution," Pornchai explained. 

Chalida     Ekvitthayavechnukul

The Nation