A coal field with a proven reserve of over 200 million tons and a potential mining life of 100 years in eastern China's Shandong Province will be left untouched for now, according to the Economic Observer.

The decision by the local government not to exploit the 120-square-kilometer coal field in Yanzhou, a county traditionally reliant on coal to drive its economy, has been seen as a triumph for environmental campaigners.

"It has not been easy to make this decision and a debate on whether or not to develop the coal field has been raging for some time," said Han Jun, party chief of the local CPC committee.

"There have been two voices. One said that we should put the coal mine into production as soon as possible and make as much money as possible. The other one said we should not ruin more land and save some natural resources for our offspring," Han said.

Early estimates show that if the mine had been put into production, the coal mine could have earned 800 million yuan (103 million US dollars) in sales income and earned the local government more than 50 million yuan in taxes each year.

The decision to hold fire comes at a time when Yanzhou is undergoing a transformation from a city dependant on its coal resources to a city driven by the development of alternative industries.

Yanzhou is listed 48th of the 100 richest counties in the country. Its coal industry now accounts for 20 percent of the local gross domestic product (GDP), down from 60 percent a few years ago.

Shandong Province has also set about establishing a strategic reserve system for its coal resources.

According to the project for local energy development between 2006 and 2010, Shandong plans to preserve some coal resources and stabilize the output of coal mines.

China has seen a total of 248.9 billion yuan invested in the fixed assets of coal projects from 2001 to 2005, exceeding the investment in past dozens of years, and a potential overproduction problem has emerged, according to the China National Coal Association (CNCA).

"Sealing up coal fields and developing them when the technology is more mature is a good way to aid the sustainable development of China's coal industry," said Niu Kehong, a researcher on coal industry management.