Puyang has never heard of the third sewage treatment plant. There is a municipal sewage treatment plant and an oil field sewage treatment plant, in the second plant, both of which are here. There is also a second sewage treatment plant under construction. I forgot the details, but I can find them. Is LZ studying environment? Me too. However, the sewage treatment plant in Puyang is a public institution, and the BOT model is under construction.