Clinton County, Kentucky

 

KARST GEOLOGY

 

The term "karst" refers to a landscape characterized by sinkholes, springs, sinking streams (streams that disappear underground), and underground drainage through solution-enlarged conduits or caves. Karst landscapes form when slightly acidic water from rain and snow-melt seeps through soil cover into fractured and soluble bedrock (usually limestone, dolomite, or gypsum). Sinkholes are depressions on the land surface where water drains underground. Usually circular and often funnel-shaped, they range in size from a few feet to hundreds of feet in diameter. Springs occur when water emerges from underground to become surface water. Caves are solution-enlarged fractures or conduits

large enough for a person to enter.

 

ENVIRONMENTAL PROTECTION

 

 

 

 

Never use sinkholes as dumps. All waste, but especially pesticides, paints, household chemicals, automobile batteries, and used motor oil, should be taken to an appropriate recycling center or landfill.

 

Make sure runoff from parking lots, streets, and other urban areas is routed through a detention basin and sediment trap to filter it before it flows into a sinkhole.

 

Make sure your home septic system is working properly and that it's not discharging sewage into a crevice or sinkhole.

 

Keep cattle and other livestock out of sinkholes and sinking streams. There are other methods of providing water to livestock.

 

See to it that sinkholes near or in crop fields are bordered with trees, shrubs, or grass buffer strips. This will filter runoff flowing into sinkholes and also keep tilled areas away from sinkholes.

 

Construct waste-holding lagoons in karst areas carefully, to prevent the bottom of the lagoon from collapsing, which would result in a catastrophic emptying of waste into the groundwater.

 

If required, develop a groundwater protection plan (410KAR5:037) or an agricultural water-quality plan (KRS224.71) for your land use.

 

(From Currens, 2001)

 

CONSTRUCTION IN KARST AREAS

 

 

 

 

Cover-collapse sinkholes (outlined in red) are typical in areas of karst geology. Many sinkholes such as these have not been mapped. The construction implications of these features must be addressed for any type of development. Photo by Bart Davidson, Kentucky Geological Survey.

 

 

RESIDENTIAL CONSTRUCTION

 

 

Limestone terrain can be subject to subsidence hazards, which usually can be overcome by prior planning and site evaluation. "A" shows construction above an open cavern, which later collapses. This is one of the most difficult situations to detect, and the possibility of this situation beneath a structure warrants insurance protection for homes built on karst terrain. In "B," a heavy structure presumed to lie above solid bedrock actually is partially supported on soft, residual clay soils that subside gradually, resulting in damage to the structure. This occurs where inadequate site evaluation can be traced to lack of geophysical studies and inadequate core sampling. "C" and "D" show the close relationship between hydrology and subsidence hazards in limestone terrain. In "C," the house is situated on porous fill (light shading) at a site where surface and groundwater drainage move supporting soil (darker shading) into voids in limestone (blocks) below. The natural process is then accelerated by infiltration through fill around the home. "D" shows a karst site where normal rainfall is absorbed by subsurface conduits, but water from infrequent heavy storms cannot be carried away quickly enough to prevent flooding of low-lying areas. Adapted from AIPG (1993).

 

 

RADON

 

Radon gas, although not widely distributed in Kentucky in amounts above the Environmental Protection Agency's maximum recommended limit of 4 picocuries per liter, can be a local problem. The bedrock composed of limestone/dolomite/shale in the county may contain high levels of uranium or radium, parent materials for radon gas. This rock and several other limestones in the state locally contain the phosphate mineral apatite. Uranium is sometimes part of the apatite structure, and when the limestone weathers away the phosphates containing uranium become concentrated in the soil and ultimately can give rise to high levels of radon. Homes in these areas should be tested for radon, but the homeowner should keep in mind that the health threat results from relatively high levels of exposure over long periods of time, and the remedy may simply be additional ventilation of the home. 

 

 

 

 

EPA recommends action be taken if indoor levels exceed 4 picocuries per liter, which is 10 times the average outdoor level. Some EPA representatives believe the action level should be lowered to 2 picocuries per liter; other scientists dissent and claim the risks estimated in this chart are already much too high for low levels of radon. The action level in European countries is set at 10 picocuries per liter. Note that this chart is only one estimate; it is not based upon any scientific result from a study of a large population meeting the listed criteria. (From the U.S. Environmental Protection Agency, 1986.)

 

EROSION CONTROL

 

 

During construction, erosion-control fences such as these may be needed to prevent silt from entering local streams. Photo by

Bart Davidson, Kentucky Geological Survey.

 

 

Riprap drainage control and erosion protection. Photo by Stephen Greb, Kentucky Geological Survey.

 

 

GROUNDWATER

 

In the central and southeastern half of the county, about three-quarters of the drilled wells yield enough water for domestic use. In low-lying areas, a few wells yield adequate amounts of water for a domestic supply, except in the northwestern corner of the county close to the Cumberland

River. In the northwestern corner, most wells are adequate for a domestic supply, especially from wells that penetrate small solution openings within the limestone bedrock.

 

Springs are present throughout the county, with flow rates ranging from several gallons per minute to 670 gallons per minute. Some springs are sufficient to supply domestic needs, but most go dry during extended dry periods in late summer and fall.

 

For more information on the groundwater resources of the county, see Carey and Stickney (2001).

 

 

POND CONSTRUCTION

 

 

Successful pond construction must prevent water from seeping through structured soils into limestone solution channels below. A compacted clay liner, or artificial liner, may prevent pond failure. Getting the basin filled with water as soon as possible after construction prevents drying and cracking, and possible leakage, of the clayey soil liner. Ponds constructed in dry weather are more apt to leak than ponds constructed in wet weather. The U.S. Department of Agriculture--Natural Resources Conservation Service can provide guidance on the application of these liners to new construction, and for treatment of existing leaking ponds. Illustration by Paul Howell, U.S. Department of Agriculture--Natural Resource Conservation Service.

 

Dams should be constructed of compacted clayey soils at slopes flatter than 3 units horizontal to 1 unit vertical. Ponds with dam heights exceeding 25 feet, or pond volumes exceeding 50 acre-feet, require permits. Contact the Kentucky Division of Water, 14 Reilly Rd., Frankfort, KY 40601, telephone: 502.564.3410.

 

WASTEWATER TREATMENT

 

 

Sewage lagoons are often constructed near industrial facilities to aid in pretreatment. Dams and embankments of lagoons like this one should be monitored for leakage, which may migrate and affect local streams and groundwater. Photo by Bart Davidson, Kentucky Geological Survey.

 

 

WASTE DISPOSAL

 

 

A large poultry processing plant near Albany uses a constructed wetland to handle wastewater treatment. In addition, process water from the plant is sprayed on adjoining fields through an irrigation system to assist in natural filtration. Photo by Bart Davidson, Kentucky Geological Survey.

 

 

NATURAL RESOURCES

 

 

The lumber industry is a common land-use feature of Clinton County. Photo by Jeff Adams, Don Molden Multiple Services Inc.

 

 

MINERAL RESOURCES

 

 

 

Limestone is a major product of Clinton County. This local quarry is a good example of land usage that requires an adequate infrastructure to handle the increased traffic of hauling vehicles. Photo by Bart Davidson, Kentucky Geological Survey.

 

 

ENERGY RESOURCES

 

 

Oil and gas development in Clinton County has been substantial in the past few years. Here an oil well with a storage tank is located adjacent to a sinkhole pond in which cattle are cooling off. It is important to consider measures that prevent releases when developing oil and gas wells. Openings to the subsurface, such as sinkhole and swallow holes, are often direct conduits to groundwater. Releases in these areas may contaminate groundwater resources. Photo by Jeff Adams, Don Molden Multiple Services Inc.

 

 

Clinton County is one of Kentucky's leading producers of oil and gas. This is a typical oil well with an off-gas flare. Photo by Jeff Adams, Don Molden Multiple Services Inc.

 

TOURISM

 

 

76 Falls is a scenic area adjoining Lake Cumberland near Albany, and is a popular location for both tourists and boaters. Photo by Bart Davidson, Kentucky Geological Survey.

 

 

RECREATION

 

 

 

The land-use planning guides on this map series take into account intensive and extensive recreation. Albany City Park is a good example of a land use that did not require much alteration of the existing landscape--it includes ball fields and playgrounds. Photo by Jeff Adams, Don Molden Multiple Services Inc.