Now that worldwide oil production is falling and oil prices are rising, more countries are turning to coal to fill growing energy needs. Unfortunately, an increasing amount of that coal is being burned before humans even get to it — to burn it themselves and at least make use of the converted energy. In many countries, a disconcerting number of coal deposits are catching fire, and for engineering and budgetary reasons, it is proving impossible to extinguish or even reach most of those fires. As a result, they can burn for decades, or longer: Australia's Burning Mountain has burned for an estimated 6,000 years, making it the world's oldest known coal fire. That particular underground fire, like many others, is naturally occurring.
Yet most such fires are man-made, and the situation is getting worse as coal mining intensifies, thus exposing more coal to open air. The coal combines with oxygen, resulting in a fuel that can ignite spontaneously at 104 degrees Fahrenheit. Human activity and lightning strikes can also spark the inflammable soft coal. The fire burns downward, obtaining air through fissures in rock and porous dirt. Once the fire works its way deep underground, it is difficult if not impossible for humans to evaluate and contain it. An underground fire can smolder for decades without revealing itself aboveground. Eventually, in a process called subsidence, burning subterranean coal turns to ash, creating massive underground caves, causing the earth above to crack and collapse, which allows in even more air to fuel the flames. In fact, most of the mesas and escarpments of the American West, resulted from vast, ancient coal fires.
The U.S., a longtime coal producer, has burning mines in many parts of the country. Centralia, Pennsylvania was once a thriving town; but a nearby extensive network of coal mines caught fire, most likely in May of 1962, when sanitation personnel began burning garbage near an old mine entrance. As a result, the fires continued burning at depths of up to 300 feet during the ensuing 43 years, essentially destroying the town. Huge swaths of vegetation were burned, leaving behind near lifeless areas. Hundreds of fissures released sulfurous gases, poisoning the air and the residents. Discarded tires and plastic lay melting in 20-feet-deep pits. In 1981, a boy almost disappeared down a sudden sinkhole that was quickly engulfed in dense gases. After that, most of the town's residents were evacuated when they accepted the federal government's relocation offer.
The government took title of Centralia, and erased its ZIP code. But some squatters remain, putting up with the sulfur fumes and the curious visitors, but also enjoying the quick-melting snow and lack of property taxes. The federal government decided that it was cheaper to pay everyone to move then to put out the fires, which are expected to burn for another 250 years, destroying 3700 acres, before running out of fuel. Similar stories can be found elsewhere in the U.S. Pennsylvania currently has 38 such conflagrations — the worst in the nation. Throughout the U.S., people are being poisoned, car-sized sinkholes are appearing without warning, and towns are slowly being destroyed.
But the greatest environmental dangers from coal fires lie outside of America.
[To be continued…]