The Haiyang 981 oil rig has entered the South China Sea again.

The China Maritime Safety Administration announced that the semi-submersible drilling rig Haiyang 981 will conduct exploratory drilling in the area with coordinates 17-29.53N, 110-57.18E from December 28 to February 10, 2016.

China's Haiyang 981 oil rig. Photo: AFP.

On its official website, the China Maritime Safety Administration stated that the Haiyang 981 drilling rig would conduct exploratory drilling in the aforementioned coordinates and prohibited all vessels from entering the 2,000-meter radius around the rig.

Speaking to Zing.vn, Major General Nguyen Quang Dam, Commander of the Vietnam Coast Guard, said that the Hai Duong 981 is currently located off the coast of Quang Binh province, 70 nautical miles east of the median line (the demarcation line in the Gulf of Tonkin between Vietnam and China). The Coast Guard will continue to closely monitor the activities of this drilling rig in the East Sea.

The Haiyang 981 rig was illegally deployed in Vietnam's continental shelf and exclusive economic zone. On May 1, 2014, Vietnam detected this rig and three Chinese oil and gas service vessels moving south from northwest of Tri Ton Island (part of Vietnam's Hoang Sa archipelago).

A day later, the Haiyang 981 oil rig was illegally deployed 80 nautical miles deep within Vietnam's continental shelf, 130 nautical miles from the Vietnamese coast. Dozens of escort vessels accompanied it. Observers considered this the most serious violation of Vietnam's sovereignty in over 20 years of Vietnam-China relations.

After 75 days of illegally placing the Haiyang 981 oil rig in Vietnam's exclusive economic zone, on July 16, 2014, China announced the withdrawal of the rig from the sea area near Tri Ton Island in Vietnam's Hoang Sa (Paracel) Islands.

The drilling rig's location (red dot) is based on coordinates provided by China. Photo: Google Maps.

Hai Duong 981 is a semi-submersible drilling rig, measuring 114 meters in length, 90 meters in width, 137 meters in height, and weighing 31,000 tons. Its deck area is equivalent to a standard football field.

According to the Wall Street Journal, the amount of steel used to build the Haiyang 981 rig is four times greater than the amount used to construct the Eiffel Tower in France. China National Offshore Oil Corporation (CNOOC) launched the Haiyang 981 rig in mid-2012. Currently, Haiyang 981 is managed by China Offshore Oil Service Company (COSL), a subsidiary of CNOOC.

According to Zing.vn