Qian Tongshuan lies quietly on a bed with a mask placed over his nose and mouth breathing oxygen. Several doctors and nurses have been keeping a close watch on him.

He is in one of the ICU rooms of the Worker's Hospital of the Zhengzhou Coal Industrial Corp in Zhengzhou, capital of central China's Henan Province.

Qian is one of the 12 survivors who were trapped underground for 109 hours last week at the Chaohua colliery of the Zhengzhou Coal Industrial Corp, which is located in Chaohua Township, in the city of Xinmin.

"It is a miracle that they are still alive after being trapped for nearly five days," said Zhang Linsen, president of the Worker's Hospital of Zhengzhou Coal Industrial Corp.

Six of the 12 miners and technical personnel who were rescued last Friday (April 16) morning are in stable condition, according to the local hospital. But the other six, who have heart problems, "are being kept under observation," Zhang said on April 20.

Zhang said all the victims were suffering from anoxia, dehydration and hunger after being trapped for 109 hours in the mine.

After six days of observation and treatment, the condition of the six with heart problems is getting better, according to Zhang. He added that it will take one more week for them to recover fully.

After he was allowed by the doctor to talk for only 10 minutes, Qian who is the deputy director of the safety team of Chaohua colliery, told Xinhua News Agency on April 19 how they survived four days and five nights underground with no food or clean water.

The following is Qian's account of those dark times.

At 4:32 on the afternoon of April 11, 12 of us went down to the 21051 work face to check a flooding problem. About two hours later at 7:10 pm, water suddenly started pouring into the tunnel where we were.

We grabbed the conveyor belt, trying to escape to a higher level in the tunnel. We climbed to a ventilator outlet where there was quite a bit of room.

Fortunately the water level began to fall not long after that and the ventilation shaft was not blocked. But we were stuck underground.

There were four technical people in the group -- Zhou Dingshuan and Li Aibin, both senior engineers, and myself and one other technician. We had a quick meeting and decided that we had to do what we could to ensure our survival while waiting for rescue teams to get us out.

We first moved to the tunnel for extracting coal gas, which was located much higher than the work face. We sat close to the water to watch for any changes in its level. Using a gas leak detector we kept monitoring the density of gas.

We, divided into six groups of two, took turns going on patrol, each watch lasting three hours. The main thing we were watching for was changes in water level.

Those who were not on duty had to sit down or sleep, neither speaking nor moving, in order to conserve energy. To save the batteries we turned off all our headlamps, except for one.

We had nothing to eat after the flood washed away the food we brought down. All we had was a bit of air and dirty water. We set a rule: Only when you were extremely thirsty could you drink water, and then only three handfuls. It was a way to prevent us from developing stomach problems. At the same time, we soaked some stakes of elm and Chinese scholar tree in water, as their bark is edible. Although in the end we did not eat any of it, we knew it might save us.

We're alive

To tell people we were alive was another thing we did. We wrote down our names and location on pieces of paper and floated them on the water, hoping they might find their way out of the tunnel. We cut plastic bags into rectangular or triangular shapes and also floated them on the water. We hoped the specially shaped pieces might let people know that we were alive and awaiting rescue. We also found a bottle of kerosene and poured it slowly into the broken water pipe, hoping people outside might smell it.

We knotted a lamp lanyard in a way to suggest the number "12" and put that in the water as well.

We were attempting to tell people all of us were still alive. Later we learned that it was the knotted lanyard that encouraged people to keep on looking for us. They understood what we were trying to tell them.

The pipe for pumping water was another important means for us to signal to the people outside. When we saw that there was less water in the pipe, we knocked on it and kept shouting into it, "Give us some air." Once, though I don't recall exactly when, we felt air blowing in through the pipe. We were wildly excited because we knew our efforts had been noticed.

Supporting one another and bolstering each other's hopes was another thing that helped us survive. When we heard the sound of a drilling machine, I kept telling my colleagues and myself that we were going to get out.

Feelings of hope and despair followed us all along. There was one crucial moment we thought we were goners when the water in the tunnel started to rise quickly. Fortunately it stopped.

Once we heard a thunderous explosion nearby. Some of us jumped with joy, thinking we had been found. But nothing happened.

Just when we could no longer stand the hunger and fatigue, our rescuers finally broke through the blockage in the tunnel.

By 9:30 am Friday morning, all the trapped men had been rescued and sent to hospital.

Zhengzhou Coal Industrial Corp claims investigation after the accident showed a nearby private coal mine had dug 320 meters into the territory of the Chaohua mine, leaving more than 60,000 cubic meters of empty tunnels, according to a Xinhua report.

Cause of the accident

The mined-out area held an estimated 28,000 cubic metres of accumulated water, which suddenly poured into a tunnel of the Chaohua mine on Sunday afternoon while work was going on, according to the investigation.

The headquarters for rescue work at the Chaohua mine, consisting of the Henan provincial coal mine administration and the safety supervision department, found that the major cause of the accident was that the coal mine administration did not carry out a thorough survey of hydrological and geological conditions in the mining area before approving operation.

With a deposit of 100 million tons, the state-owned Chaohua coal mine had been open for about 11 years with an annual output of 2.4 million tons, according to Su Wanli, who heads the colliery.

Chaohua resumed production on April 18 after all 12 trapped miners were rescued.

The Henan provincial coal mine safety authorities have called on all local coal mines to carry out safety inspections to identify areas in danger of flooding and to make preparations for the rainy season.

(China Daily April 23, 2004)