"By December 3 last year, the area of worked-out and sinking coal mines surpassed 700,000 hectares, causing economic losses of over 50 billion yuan (US$6 billion)," said Li Lianji, a researcher from Shanxi Province's Social Sciences Academy.

A report on the issue, chaired by Li, was recently submitted to the State Council and said that worked-out and sinking mines account for one tenth of the country's total coal mining area.

Shanxi in the north of China has been affected most by the resulting accidents. Of the province's 150,000 hectares, over 20,000 are made up of worked-out mines, one seventh of the total. Up to now, 6,000 square kilometers of worked-out areas have suffered geological disasters.

Besides huge economic losses, over 500 people have been killed in these disasters over the past 10 years.

In the northeastern province of Heilongjiang, Qitaihe City has sunk 2.5-6.5 meters since coal mining began there in 1958. About 63.73 square kilometers of the Jixi mining area has experienced subsidence, the deepest site having sunk 30 meters with a six-meter-long crack in the ground. The area is still subsiding at a speed of 1.3 meters per year.

"Our company had to spend tens of millions yuan to control subsidence and compensate local residents and factories for the damage caused," said Bai Yuecheng, senior engineer from Hebi Coal Co. Last year, the finance ministry gave them several hundred million yuan in order to pay their debts.

Yet coal producers seem to continue to invest heavily in remedies and compensation only after serious subsidence occurs, rather than spending money to backfill sites in order to prevent it.

"The funds needed for backfill are far more than that for compensation," explains Bai. Subsidence is usually only detected in the longer term, and this fails to outweigh producers' drive for quick profits.

"Worked-out and sinking mines in east China have resulted in severe devastation to local fish pools, roads and farmland, probably the cost we must pay for obtaining coal resources," said Chen Qi with the China Coal Industry Association.

But the high cost of backfill and its unsatisfactory effect, Li Lianji said, was an excuse used by coal mine managers for not taking preventative measures.

"Since the cost of prevention is high, it should be reflected in the price of coal," pointed out Li. He said that previously, environmental factors have been made artificially cost-free.

The National Development and Reform Commission (NDRC) announced a price linkage mechanism in December to allow energy prices to float in line with coal prices, but only within eight percent. Many coal producers have complained that this range is too small.

"The government has benefited from fixing coal prices, so now that it is aware of the resulting problems it has a responsibility to play a role in compensation and control," said Li.

Government funds will be provided to reclaim subsided land, compensate local residents, and harness underground and surface water.

Once coal producers have assessed and reported on the amounts of money involved, the NDRC will allocate funds to boost prevention and control of the problem.

"The problem of worked-out mines is inevitable, but subsidence can be prevented," said Li. His idea to prevent subsidence is strengthening monitoring and to draw lessons from developed countries with high coal production such as the US and Canada, adopting methods of filling sunken areas with waste rock, sand or cement.

(eastday.com translated by Zhang Tingting for China.org.cn, January 22, 2004)