Just to clear one thing, this placed is not the other place named Huangyangtan which is undergoing anti-dessertification. That Huangyangtan has the same chinese name but it's in Heibei province (another province). That can ruleout using a anti-dessert facility as a cover-up.
Dont think the cost of that model is that high, since the labour cost around there is next to nothing. Thus, using the liberation army, means anything could be done will be done.
added info: Huangyangtang supposed to be a state-own experimental farm with 4 acres of land and use US imported irrigating machinaries. It is also one of the vineyards of a chinese winery. By overlaying a vincinity map over it, the houses to the east of the establishment are supposed to be farm houses. The hill to the southwest of the facility is called Fabuzhan in the map. The closest large town to the east which marked Shengli in GE is actually called Yongling.