Promoting the integrated high-quality development of Tongzhou District in Beijing and the three counties and cities of Sanhe, Dachang and Xianghe in Hebei Province is a key task in the "14th Five-Year Plan" to promote the coordinated development of Beijing, Tianjin and Hebei. Tongzhou District and Beisan County have signed an agreement to strengthen the ecological environment management in the border area, and unified management and control in five aspects: regional air pollution prevention and control, river basin water environment restoration, soil pollution control, garbage disposal, and water resource utilization.