Not sure if you mean financial cost, or possibly environmental / human losses - but since it's in the middle of a desert, I assume they're trying to minimize the risk?
The sources you've listed don't seem to show any environmental damage. In fact, China has been leading among major nations in environmental protection efforts in recent years. For instance, the destruction of natural forests has been virtually halted, and China has been the most successful country in combating desertification through massive reforestation projects.
Ironically, some Western media outlets are now criticizing China for "having too many trees" and reducing desert areas across the globe.
