BEIJING, Jan. 9 (Xinhua) -- China's top work safety watchdog said on Thursday that pipeline corrosion causing oil leakage into the sewage network and poor work conduct led to the fatal explosions that rocked Qingdao City of east China's Shandong Province late last year.
The blasts, which occurred on Nov. 22, left 62 people dead and 136 others injured, and caused economic losses of 750 million yuan (122.7 million U.S. dollars).
The major cause of the incident was corrosion that wore down the pipeline and made it break. Meanwhile, work on a sewage cover plate on the day of the accident used a hydraulic hammer that wasn't explosion-proof, producing the sparks that triggered the blasts, said Huang Yi, spokesman for the State Administration of Work Safety (SAWS).
He said that the blasts have been identified as a "responsibility incident." The investigation report has been sent to the cabinet for review.
Lack of responsibility in major hazards inspection and weak emergency response from both pipeline operator Sinopec and local government departments were also exposed through the incident, Huang said.
He added that disorderly municipal design at the work site also brewed security risks in that the oil pipeline was shared with the municipal sewage network and installed at a range too close to nearby buildings.
According to government data, China's total domestic mileage of oil and gas pipelines stands at 102,000 km, with some of it having served for as long as 40 years. The old rusty pipelines, some intertwined with municipal networks, pose major risks.
A special government overhaul of nearly 3,000 petrochemical companies and oil storage facilities since Nov. 22 has revealed nearly 20,000 potential hazards, which are currently being treated, said Wang Haoshui, an SAWS inspector in charge of petrochemical work safety.