Thanks to some fine enterprise reporting by Emily Walkenhorst of this newspaper, we’ve learned the index created by academics at the University of Arkansas at Fayetteville to measure levels of potentially contaminating phosphorus leaking from the surfaces of agricultural fields during rain has failed to include that which invariably drains through and into underlying karst terrain.
To that revelation I say: Oh, come now. You have to be kidding.
Excess nitrogen and phosphorus in water, both fertilizers generated by animal waste, cause algae to grow faster than ecosystems can handle, and result in danger to aquatic life from explosions of algae blooms and resulting low dissolved oxygen. Did you try canoeing through the mess along some 70 miles of the Buffalo last summer?
Agvise Laboratories reports that many states, out of environmental concerns over excess phosphorus application and runoff, are now regulating animal manure application, focusing first on its phosphorus content, followed by nitrogen.
I’m assured that streams such as our beloved Buffalo National River don’t care whether contaminants originate from runoff or subsurface fissures and cracks.
The excess fertilizer that attaches to soil particles and becomes trapped in the subterranean fractured limestone openings becomes known as legacy phosphorus. Unlike runoff, it can steadily pollute for decades and much longer.
The so-called Arkansas Phosphorus Index, developed in 2010, is primarily used by farmers, although processing plants and municipal wastewater plants have started applying it as well.
The index was established by Andrew Sharpley, a professor in the Agriculture Division’s Department of Crop, Soil and Environmental Sciences at UA, and others. Sharpley also heads the Big Creek Research and Extension Team.
That group, comprised largely of members of the University of Arkansas Agricultural Division, has received hundreds of thousands of taxpayer dollars over the past six years to monitor potential waste discharges, including phosphorus, from C&H Hog Farms.
I wonder, with all that expertise and an obviously inadequate Phosphorus Index, why this monitoring group hasn’t been taking carefully measured accounts of all known ways phosphorus enters natural waters statewide, especially where it is widely known the Buffalo watershed surrounding C&H is riddled with karst.
Walkenhorst quoted Brian Haggard, director of the Arkansas Water Resources Center at the UA’s College of Engineering, saying the variability of karst terrain means it shouldn’t be factored into the index. I suppose that means let’s pretend like it doesn’t exist. I’d sure want karst included in Mikey’s Imaginary Updated and Remarkably Complete Phosphorus Index.
The existence of pervasive karst in our Buffalo watershed is well-documented, including in caves and underground springs that honeycomb the rocky hills and mountains.
Water flow tests voluntarily conducted by emeritus Arkansas geoscientist and noted hydrologist Dr. John Van Brahana—not by our state—showed that dye he injected into property surrounding C&H traveled rapidly, was widespread and emerged as far as 12 miles downstream in the Buffalo.
“The state’s hog farms—and neighboring fields where hog manure is used as fertilizer—are often in karst areas in north and southwest Arkansas,” Walkenhorst wrote. “More often than not, the soil on which the manure has been spread has phosphorous levels that are considered excessive for plant nutrition, according to an Arkansas Democrat-Gazette review of the permits and soil analysis samples of about 100 Arkansas hog farms.”
The index, Walkenhorst wrote, “assigns a phosphorous-runoff risk value to land upon which a farmer wants to spread animal waste. Manure can be applied only on land deemed to have a ‘low’ or ‘medium’ risk of runoff, according to the Arkansas Department of Environmental Quality.”
The index multiplies three things together, according to the story: “phosphorus source potential (based on soil tests and the phosphorous application rate), transport potential (how easily phosphorus might move, based on the slope of the land and other elements), and best management practices (such as ponds, fencing or buffers on the land). Each of the three factors has its own factor that determines its value. Factors are assigned numeric values, even when they are not actual measurements, such as … how often an area of land floods. … Soil samples help to recalculate the land’s risk every year.
The Department of Environmental Quality (cough), which should never have approved the factory with up to 6,500 swine in this incredibly environmentally sensitive region without extensive testing, last year denied it a new operating permit.
The factory’s initial Regulation 6 permit issued in 2012 was discontinued and expired two years ago. Yet the factory has operated as usual since because of ongoing legal appeals.
In part, the agency, in its final permit denial last fall, was concerned about the presence of karst, the measurably increased phosphorus levels and the now-documented impairment of the nearby Buffalo River, Walkenhorst wrote.
C&H sprays the swine manure as fertilizer on surrounding fields along and near the Buffalo tributary, Big Creek, flowing six miles down into the Buffalo.
Jessie Green, executive director of White River Waterkeeper, told Walkenhorst the phosphorus index should have accounted for subsurface leakage. The fact it doesn’t is “a considerable failing.” Hmmm, ya think?
Sharpley said the index was designed only to measure surface phosphorus runoff in rain and is finally being updated to account for local conditions such as karst.
The original C&H permit application and nutrient management plan failed to account for the acres of karst upon which it has freely operated. Where was the Department of Environmental Quality in 2012?
Unbelievable stuff, eh?
Mike Masterson is a longtime Arkansas journalist. Email him at firstname.lastname@example.org.