The power plant gives importance to the compliance with preventive and remedial measure of environmental impact and measure of environmental quality monitoring specified in the report of Environmental Impact Assessment (EIA). The power plant has conducted strict control of the pollution from the generation process and ensured that the value of the pollutant from the power plant does not exceed the standard. The pollutant control system is as follows:

Air quality

The steam or water injection system is installed at the gas turbine of Wang Noi Power Plant, Block 1 and Block 2, whereas Block 3 and Block 4 are equipped with dry low NO_x burner system to reduce the temperature in the combustion chamber and decrease the rate of nitrogen oxide (NO_x) emissions. Moreover, emissions monitoring system (CEMs) is installed at each stack of the power plant.

Water quality

The power plant has the wastewater treatment system using microorganism for wastewater from the buildings. Wastewater from electricity generation process is treated in the neutralization pit and wastewater contaminated with lubricating oil is treated in the oil separator. The treated water, including water from the cooling tower is stored in a holding pond for precipitation and the retention pond to reduce the suspended solids, solution, and conductivity before being discharged into Canal No. 26. Moreover, the equipment to monitor water quality is installed at the Water Quality Building to monitor the quality of wastewater in terms of acidity and alkalinity, temperature, conductivity, and dissolved oxygen before the discharge.

Waste management

For the garbage from the office building, the authorized companies are contracted to collect garbage for disposal. For waste from the electricity generation process such as waste resin, used oil, and waste oil, the disposal is conducted in a technically correct way by the company which is authorized by Department of Industrial Works, Ministry of Industry. As for sludge cake from the water production process, the power plant is authorized by the Director General of Department of Industrial Works to use the sludge cake to fill the lowland in the power plant area. (Letter of Department of Industrial Works of Or Kor 0313/5763 dated May 19, 2003)

Noise level

The silencer is installed in the power plant to reduce the noise from the steam. An enclosure is provided for the machinery at the combustion chamber of gas turbine. The noise from the machinery and equipment is limited to 85 dB (A) or at a distance of 1 m from the noise origin. The noise level is monitored according to law. A notice or symbol to indicate the area where the noise is over 80 dB A is provided. Devices for noise protection such as earmuff or ear plug are provided for the employees working in the area of loud noise over 80 dB A.

Aquatic ecosystem

Wang Noi Power Plant has installed a screening at the water pump and has kept it to be in good condition. Aquatic species are frequently released into Raphee Phat Canal and Canal No.26.

Analysis has been conducted on the types and an amount of plant plankton, aquatic plankton, and benthic animals twice for each pond, at Raphee Phat Canal and Canal No. 26. The analysis at 4 points include

• In Raphee Phat Canal: The area where raw water is pumped in (at the water gate)
• In Canal 26: The area where wastewater is discharged from the power plant
• In Canal 26: the area 500 m downstream of the point of wastewater discharge
• In Canal 26: the area 500 m upstream of the point of wastewater discharge

Apart from strict operation according to the defined measure, the power plant has voluntarily participated in several environmental activities such as carbon footprint calculation of the power plant in 2014 and received the Certificate of Carbon Footprint for Organization from Thailand Greenhouse Gas Management Organization (Public Organization) on September 19, 2014.

Moreover, the power plant received other awards which include:

• CSR-DIW Continuous Award from the Ministry of Industry, on July 28, 2016
• Green Industry Award, Level 4 from Ministry of Industry, on September 11, 2017
• Certificate of “Environmental Governance Project” on September 28, 2010
• Excellent Award for “State Enterprise which has developed to be Excellence of Driving the Work Plan, Upgrade the Level of Integrity and Transparency in Operation” on September 18, 2017 from the Office of the National Anti-Corruption Commission
• Certificate of ISO 14001 in 1999