One of the interesting places to visit in Centralia, Pennsylvania is the mine drainage tunnel. You can find this by heading east on Big Mine Run Road (PA 2004) away from Centralia. As you go down over the hill, you’ll turn a bend in the road and continue south towards Ashland.
Keep looking to your right. Eventually, you will see guardrails and a little bridge that runs over an yellow-orange stream. This is the acidic water coming out of the tunnel. Pull over and follow the stream to where it begins. Here is the Centralia mine drainage tunnel portal.
The tunnel was originally constructed to drain the mines that were further up the hill under Centralia, Pennsylvania. As the mines went deeper into the mountain, they began to encounter ground water. By digging a tunnel below the the mines, the water was able to exit and lower the water level in the mountain. This helped to keep the mines dry without the need for additional pumping.
The tunnel caused two main problems which aid the Centralia mine fire. First, it lowered the water level in the mines. This enabled the fire to go deeper into the mine and burn for longer.
Second, the tunnel opening provided an excellent source of oxygen necessary to feed the huge fire. Because the fire was burning above the tunnel near the top of the mountain, it created a massive updraft that pulled air from the drainage tunnel and helped to keep the fire burning steadily for years.
It has been frequently suggested that if the Centralia mine drainage tunnel were closed, the fire might be extinguished. However, considering the number of fissures, cracks, and other openings all over the mountain, the mine fire would likely have other sources of oxygen.
Also, Pennsylvania’s Department of Environment Protection (DEP) has said that while closing the tunnel portal would cause the water level to rise, it is doubtful it would go high enough to reach the uppermost areas of the fire. Additionally, such a plan would be high risk. A rising water level within the mine might cause blowouts elsewhere that could cause significant damaged. The mine geyser near Ashland is evidence of this.
Today the Centralia mine drainage tunnel is a neat point of interest near the town. Though, be careful if you visit it. The water is acidic and contaminated with metals and other chemicals coming from the former mine.