HOHHOT, May 15 -- A major coal stock piling ground in Inner Mongolia will soon become dust free, as construction of the world's largest enclosed coal logistics park started on Thursday.

The park in Baotou City slated for completion by the end of this year will be enclosed by a pneumatic membrane and steel structure.

The park, where more than 300 firms kept their coal stock and covering 320 hectares, will be half covered by the inflatable structure.

Baotou city government have decided to shut down the open-air coal business to curb dust pollution.

Two investors -- CITIC Logistics and Beijing Zhongke Construction Investment Co. Ltd. -- have jointly invested more than 1 billion yuan (160 million U.S. dollars) in the building. The park will retain its former capacity of 30 million tonnes in annual coal throughput.