Mass Rapid Transit Authority of Thailand (MRTA) by Environment Division, MRT Project Development Department inspected the compliance with mitigation measures on environmental impacts in construction sites of the MRT Yellow Line Project: Lat Phrao – Samrong Section from Lat Phrao Station on Lat Phrao Road to Samrong Station on Thepharak Road. The inspection activities consisted of the contractors’ compliance with measures on reduction of PM 2.5 such as covering of soil, sand, and construction waste, installation of opaque fences around the construction site to clearly show the boundaries of the project construction area as well as installation of sound barrier at Chok Chai 4 Station, and instructing the workers to adhere strictly to mitigation measures on environmental impacts and preventive measures of COVID-19 regulated by Ministry of Public Health.