Tag Archives: karst

Karst Topography and the Buffalo National River

In August 2012 a hog factory with as many as 6500 hogs was permitted by the Arkansas Department of Environmental Quality (ADEQ). The permitting process employed what is called a Regulation 6 General Permit. In itself this is somewhat unusual as Reg 6 is usually applied to things like wastewater treatment facilities, or construction sites with concerns for managing storm water run-off. There are two types of Reg 6, individual and general. The permit used in this case was the general permit – it has no location or site specific considerations. Along with the general permit is a Nutrient Management Plan (NMP) that allows for the dispersal of agricultural wastes,in this case liquid pig manure, in a fashion which shouldn’t burden the soils with nutrients in excess of what can be absorbed on designated fields.

The problem is that this particular factory is sited on a Mount Judea, AR location on Big Creek, a tributary of the Buffalo National River. If hog manure is spread on the land in excess of the amount that the grasses can absorb, there may be nutrient pollution of Big Creek and and the Buffalo.

In August of 2013 Governor Beebe allocated several hundred thousand dollars to fund a research effort to examine the risk of pollution to the Buffalo. Professor Andrew Sharpley University of Arkansas Division of Agriculture is leading what is called the Big Creek Research and Extension Team (BCRET)

In April 2014 the Pollution Control and Ecology (PC&E) Commission began a moratorium on any new medium to large hog operations (Confined Animal feeding Operations – CAFO.) The data is mixed as to whether pollutants are running off the hay fields where the manure is spread and into Big Creek, then down to the Buffalo.

An important and confounding feature of this hog factory is that the local topography appears to be underlain by karst, a particularly porous limestone that is prone to sink holes, caves and springs. Water and anything in it will move rather rapidly through the subsurface terrain and contaminate locales distant from the site.

Two types of studies have been conducted that confirm the karst. Dr Van Brahana, emeritus Professor of Hydrogeology University of Arkansas, has done dye tracing in the area. He and his coworkers bore a hole in the ground, add a specific dye solution and then monitor the surrounding aquifers for presence of the dye. Dye added in close proximity to the farm spray fields resulted in detection of the dye in 44 remote sites, 14 of which were in caves and springs near the river and 3 in the Buffalo itself.

Professor Todd Halihan, Professor of Hydrogeology Oklahoma State University, utilized another technique to test for the presence of karst. He employed Electrical Resistivity Imaging (ERI) across several transects very close to the ponds holding millions of gallons of liquid hog wastes. He found not just porosity but what he believes to be a major fault which is allowing movement of wastes into the subterranian aquifers, confirming Brhana’s dye studies.

Sadly neither of these studies were conducted by the BCRET, and hence have been ignored by the ADEQ and the PC&E commission which oversees the ADEQ.