Are there really pollution-free places in China (including local underground water sources)? Please tell me why there is no pollution in these places you mentioned.

Yes, deep in Daxinganling, Heilongjiang. Where I was stationed as a soldier, there were no plastic products, and oil lamps were lit at home. There is no chemical fertilizer in the field, only farmyard manure is used. Without agricultural machinery, oxen and horses are used to plow the fields, and they work at sunrise and rest at sunset. If an outsider enters, he will be welcomed and entertained by the whole village. * * * There are three families. However, there will also be some cunning psychology. Children often watch our army's vehicles showing movies outside the village. Once they are found, they will report to the village immediately. The adults in the village will immediately put their heads on the road, stop the traffic, and then discuss with a firm tone and show us a movie. When you want to refuse, you will smell the smell of meat coming from nearby, and they will tell you with a sly smile that the movie will be put on first, and then the pork will be stewed with rice noodles.