Toxic gas leak leads to partial shutdown

Emission of serious toxic carbon monoxide (CO) gas has forced the Barapukuria Coal Mining Company Ltd (BCMCL) in Dinajpur to reseal yesterday a mining area that was only reopened two weeks ago after being closed for nearly two years.
As a result, the target coal production of the mine has once again dropped to half. Consequently, the mine will once again fail to provide enough coal to run the Barapukuria 250MW coal-fired power plant adjacent to the mine site.
The daily coal production target of the mine is 3,000 metric tons (mt), of which the power plant requires about 2,400mt.
A set of mining equipment worth $ 5.5 million has also been stuck inside the 1,100 feet deep sealed area of Phase 1110, a competent source at the BCML said. The mine will continue to produce coal from another phase using another set of equipment.
"We have been noticing an alarming rise of carbon monoxide emission for the last two days. We had been extracting the coal amid high risk. But the level of emission today has become too dangerous for any human being to work in," said a source.
In early October 2005, to avert a disaster caused by emission of toxic gases as well as a threat of self-combustion, the mining authorities sealed off the Phase 1110 of the mine along with the expensive mining equipment. It became very difficult to reopen this phase as it was filled with carbon monoxide and methane gases.
Since April this year, the BCMCL with the help from Chinese experts has pumped in huge volumes of chemicals inside the sealed-off phase to reduce carbon monoxide before reopening it on August 18. It resumed coal production from this phase from August 22-23, rekindling the hope to turn this troubled mine financially viable.
But the hope was a short-lived one as the BCMCL authorities decided to seal the area yesterday considering the imminent threat the CO emissions pose on human health. Inhaling a small percentage of CO can kill any human being, said experts.
"We will now review our past mistakes. We shall see whether we needed to inject more nitrogen back in April to July to eliminate risk of carbon monoxide emission," said a source at BCMCL.
The BCMCL produced 2,200 tons of coal from this phase alone on Monday and another 1,000 tons yesterday till deciding to seal it off, he added.
Combined with coal production from another phase, the BCMCL was producing over 3,200mt coal every day for the last 12 days -- enough to cater to the requirement of the Barapukuria 250MW power plant. Prior to the reopening of the Phase 1110, it was all set to import coal for the power plant from Indonesia due to ongoing coal shortage.
Now the Power Development Board (PDB) would once again have to rely on imported coal to run its Barapukuria 250MW power plant.
It is not certain when this phase could be reopened. "In the best case scenario, it will take several more months," the source pointed out.
This phase of the complex underground mine gives access to 2.30 lakh tons of coal, which has a production value of at least $100,000.
On October 4, 2005 the BCMCL shut down the mine's production phase 1110 due to deadly saturation of gas.
On April 4, 2006 Chinese contractors tried to unseal the area to recover the costly mining equipment. But it had to be re-sealed on April 7, 2006, as the gas situation inside it was precarious.
Then from April, 2007 the mine's Chinese operators led by CMC, with help of consultants from China University of Mining Technology, started injecting nitrogen into the sealed area to reduce oxygen and to eliminate chances of self-combustion.
On August 18, a team, with the backup of fire services, medical teams and a backup power system, started unsealing the area.
The Barapukuria coal mine project was approved in March 1992 at a cost of Tk 887 crore under Chinese Supplier's Credit with the completion target of July 31, 2001.
Project delays and severe corruption hiked up the project cost to over Tk 1,600 crore. So far, the government has paid off more than Tk 600 crore to China.