What is Karst, and Why Should We Care?

When I was a first-year student at the University of Virginia I was required to take a science course. The choices were physics, chemistry, biology or geology.  “Rocks” is what the students called geology and it was reputed to be the least rigorous, so that’s what I took. It was a good choice.  We learned about the various types of igneous rocks, and minerals like quartz and feldspar. One of the funniest things I ever saw scrawled on a bathroom wall was that geology professors Ellison and Earn “had committed hornblende together.” But I sense I am losing my way here.

Sedimentary rocks constitute another major category. Some sedimentary rocks are formed in oceans from small pieces of other rock and organic debris in the water that settle out and are compressed over millions of years. Limestone and dolomite are sedimentary rocks of this type. Those of us who live in the Shenandoah Valley, including West Virginia’s Eastern Panhandle, are living atop great areas of limestone.

When the underlying rock in an area is hard, surface water features such as streams and lakes area plentiful. But when it consists of soft rock, like limestone, there are fewer surface water features because all the rainfall quickly seeps into the ground through cracks and fissures. In our area groundwater is where the action is. It moves around much more easily in limestone than in harder underlying rocks. Groundwater creates all sorts of interesting and sometimes dangerous underground features in limestone like caves and sinkholes.

The name for geologic areas like ours is karst terrain. Karst formations have high rates of permeability, resulting in reduced opportunity for contaminants to be filtered. While surface water like lakes and rivers are easily polluted simply by dumping contaminants, groundwater in karst terrain is just as easily polluted. That matchless research source Wikipedia tells us that “sinkholes have often been used as farmstead or community trash dumps. Overloaded or malfunctioning septic tanks in karst landscapes may dump raw sewage directly into underground channels.”

One of the chief complaints of the opponents of the Rockwool industrial development is that groundwater pollution from its operations can easily pollute drinking water sources for a large number of residents. A December 1, 2020 article in the WV Independent Observer noted that there were 100 wells within the 1-mile “buffer zone” surrounding the Rockwool plant. Much of the domestic drinking water in Jefferson County comes from wells – in 2011 approximately 679 million gallons per year. This is common throughout the state. The West Virginia Legislature has found that ninety percent of the state’s rural population depends on groundwater for drinking.

Industrial sources of groundwater pollution are not the only concern.  The Eastern Panhandle is undergoing rapid housing development and other building. Any activity that disturbs the surface is a potential source of groundwater pollution.

Perhaps the best we can do is to monitor our groundwater carefully during this phase in our development. If that monitoring reveals hard evidence of groundwater pollution, then action can be taken before it is too late. That is the approach taken by a bill introduced in the last regular session of the Legislature by Del. John Doyle (D-Jefferson) and several others. The bill, known as HB 2980, sought to amend the Groundwater Protection Act by adding protections in karst terrain.

HB 2980 would have required any application for a permit, license or registration for activities that may affect groundwater in karst terrain to contain a groundwater contamination risk assessment, a design proposal for structures to contain any risk, and a water monitoring and contamination response plan at the site.  Anticipating opposition from small business, the bill allows the Department of Environmental Protection to exempt activities having a de minimus effect on groundwater.

As with most environmental bills in the Legislature, HB 2980 died in committee without receiving a vote. The bill will be reintroduced in January 2022 at the next regular session and Del. Doyle has received assurances that the bill will get at least a hearing in committee. If you are inclined to contact your legislators on environmental matters, this bill should be at the top of your list.