WHAT ROCK ARE YOU LIVING ON? (Part 1 of a Series)

(Part 1 of a Series)
By Frank Waksmunski
The Times News, Lehighton, Copyright, 2004: The Watering Whole

April 29, 2004

Ever since I was a kid, I’ve enjoyed car rides through the mountains, especially where the mountain was cut to put the highway through. There I could see different kinds of rock, and no two cuts were the same to me.

I lived most of my life on flat ground, but now I’m living in the mountains and I’m taking more of an interest in those rocks. I have a well drilled into them for my drinking water.

You can catch glimpses of Carbon County’s rocks (geologic formations) when you pass through the cuts, whether made by man or Nature. Route 209 South into Jim Thorpe is a great example.

During the winter, massive ice flows cover the face of the rock. This ice is a solid picture of drinking water. It’s an above ground example of what’s going on underground. Water trickles through cracks in the rocks, and we can pump it out through our wells.

There are no underground lakes in Carbon County, just rocks holding water in cracks and spaces around them. Those rocks are soaking in water, which has the uncanny ability to dissolve some of the rock and deliver it to our tap.

If you look at a geological map of Carbon County, it resembles a patch quilt of different geologic formations. You could be living on, and getting your drinking water from Coal Measures, Pottsville Conglomerate, Mauch Chunk Red Shale, Pocono Sandstone, Catskill Rocks, Chemung, Genesee, Hamilton, Marcellus, Oriskany Sandstone, Lower Helderberg Limestone, Common Red Shale, or Medina and Oneida Sandstone formations.

Each type of formation has its own characteristics, which affect the quality and quantity of groundwater.

Knowing a little bit about geology will make you aware of the diversity of rocks in the county. If you and your neighbor have private wells, you would think you’d have the same water quality. You might, but don’t bet on it. It could be completely different.

I spoke with two people who are next-door neighbors. Their wells were only about 150 feet apart. One was pumping out so much rust that the owner couldn’t replace his filter fast enough, yet the other had no rust problem at all.

Some rocks are better than others, water-wise that is.

Whether it’s municipal or private well water, if you have good water you can give some credit to the rocks in the area of the well. Conversely, those rocks can give you some pretty awful water and a host of problems.

Of course, like most things in nature, relationships between rocks and water aren’t simple. Whatever formation you are on, there is always some variation.

The Appalachian Mountains are about 275 million years old, and were formed by the collision of plates that form the earth’s crust. They were literally pushed up out of the ground, and may have been as tall as the highest Alaskan peaks are today. Erosion has brought them down to the level we see now.

In Part 2 of this series, I will write about the different geologic formations in Carbon County and where they are, so that you can have some idea about what rock you might be living on.

The Carbon County Groundwater Guardians is a 501(c)(3) nonprofit, volunteer organization that welcomes your comments, questions or ideas for future articles. For more information or to get involved, call (570) 645-8597, visit www.carbonwaters.org, or write to P.O. Box 104, Palmerton, PA 18071.