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Scientists go underground to check water quality.

The gate's shut and the stick trap is set," Derek Hall says. That's the signal for Doug Boyer to move on through the Hole of the Devil.

Boyer points to the jaw and leg-bones on the ground, the stark remains of a long-dead farm cow. Then he squeezes, winds, crawls, stoops, glides, jumps, splashes, plunges, soaks, wades, and slithers his way through the muddy, narrow passage called The Bathtub and Barefoot Creek.

The stick trap is placed strategically so it will be knocked down by anyone entering the cave behind Boyer and Hall. They don't want to lock the gate on the way out and accidentally seal any adventurer in The Hole's caverns.

Despite the challenge of negotiating the series of bathtublike holes along the tight, 400-foot-long entrance passage, The Hole has turned Boyer into a spelunker, or cave explorer. An Agricultural Research Service hydrologist in Beckley, West Virginia, Boyer has come to see caving as a way to get a worm's eye view of agricultural pollution. "Caves are Nature's drainage pipes," he says.

In fact, Bill Edwards - an ARS soil physicist in Ohio who studies earthworm tunnels as macropores that can funnel farm runoff downward toward groundwater-once accompanied Boyer on a caving expedition. He'd been intrigued by Boyer's boast that "we have macropores big enough to walk through."

Says Boyer, "Besides size, another difference between wormholes and caves is this: Caves descend hundreds of feet, to deep groundwater, while nightcrawler holes go down only a few feet. And sinkholes above the caves can act as giant funnels directing farm runoff water into caves. We're concerned because cave streams feed surface springs and wells used for drinking water."

Boyer is often accompanied by Hall, who works summers for ARS. He is an avid spelunker and a geology student at Virginia Polytechnic Institute and State University, Blacksburg, Virginia.

When they make their serpentine journeys through The Hole, they are creeping under the 6-square-mile Hole Basin in Greenbrier County in southeastern West Virginia. The area's unstable topography is the result of underground water flowing through limestone bedrock and forming caverns, sinking streams, and sinkholes.

The sinkholes are ground-level depressions formed as surface water moves through fractures in limestone, often draining into underground passages. The water dissolves and breaks up the limestone as it goes along, eventually flushing away limestone pieces as it carves out underground passages.

Over time, the ground above collapses, forming surface depressions resembling potholes. Some view sinkholes as being like injection wells through which water, along with any chemicals that are either dissolved in water or attached to small particles, are channeled into groundwater.

The Hole is one of several drainage basins in West Virginia's Greenbrier River Valley watershed, which is one of 37 chosen in 1990 as demonstration sites for providing intensive educational and technical assistance to farmers. Each of the watersheds was chosen because the potential for agriculture-related problems to develop had been identified in state Clean Water Act reports to the U.S. Environmental Protection Agency.

The hydrologic unit demonstration and research project is part of a larger research and demonstration project under the Department of Agriculture's Water Quality Initiative. The initiative is designed to help farmers comply with state pollution management programs authorized by the federal Clean Water Act of 1987.

The project's purpose is to ensure that surface and underground water supplies are protected through safe use of fertilizers, manure, and pesticides.

"We want to understand waterflow in limestone so the USDA Soil Conservation Service can show farmers the best ways to protect underground water supplies," Boyer says.

As part of the water quality study, Boyer samples Greenbrier Valley springs at least weekly, with occasional samplings of the less accessible cave streams. He checks for nitrate from fertilizers and manure, as well as for herbicides.

Life Underground

Shade-seeking cows usually watch Boyer and Hall as they change into long underwear, extra layers of clothing, helmets, and overalls - despite sweltering summer heat. As the cavers descend toward the entrance, they are immediately refreshed by a flow of cool air from the cave, their breaths condensing from the cave air.

The entrance called Gibbs that Boyer unlocks this day is one of three used by the scientists to access this totally dark underworld illuminated only by odoriferous carbide gas lamps attached to the cavers' helmets.

Nothing can see in caves without these lights. Foxes and raccoons depend on a scent trail to enter and exit through both the human entrances and possibly smaller, unknown ones. Bats the size of very small mice come and go via tiny cracks hidden by pasture grass, navigating around cave curves and human cavers by bouncing sound waves off them.

Many creatures seek the cool of cave interiors during summer because, says Boyer, "Caves always stay at the average annual temperature of an area. In West Virginia, it's 54 degrees."

Armies of cave crickets enter and leave through their own secret passages, with two-thirds of their forces from each day's outing always remaining in the cave, for unknown reasons. Salamanders scurry blindly up cave ledges as mostly flatworms move about in the fishless underground streams. Sometimes an earthworm falls into a cave stream and survives to reproduce offspring with slightly different band markings probably caused by the absence of light.

A biologist Boyer once took to the stream was disappointed by the lack of diversity in stream life, a possible indicator of pollution.

Limestone Caves

The Hole is called a contact cave because it was formed by water steadily carving out the limestone down to where it met an insoluble layer of shale. The cave entrances formed where the shale layer surfaced and became a surface streambed.

Crawling over the crumbly and noisy shale pieces that line the creek beds, Boyer and Hall follow the shale steadily down, usually at a gradual 3-to 4-degree slope. Following Barefoot Creek's more abrupt drops and continuing on through aptly named formations like The Long Room, The Crossover, Adjacent Stream, Spike Street, Bullwinkle Boulevard, Broken Crockery Passage, and The Maze, they are soon hundreds of feet below the basements of farm houses and barns, cow pastures, and cornfields.

Bullwinkle Boulevard gets its name from a calcite formation that bears an uncanny resemblance to the cartoon character Bullwinkle Moose. Spike Street is marked by a spike made of gypsum crystal.

Stalactites and stalagmites decorate the passages, sometimes flowing like stage curtains, other times meeting to form columns.

There are 38 farms above The Hole - two dozen that raise cows and calves, a dozen dairy farms, and two turkey farms.

The Hole has a bad reputation among cavers because of the 4-foot-high Bathtub passage and many miles of other small crawlways. It was named after Holloch Cave in Switzerland, where Holloch means hole of the devil.

The Hole consists of 23 mapped miles of labyrinthine passages carved by the Shale River and its tributaries as they wound their way down hundreds of feet below the surface. Some of the passages lie one above the other, at different levels. Over centuries, the water ate away much of the limestone layer at its point of contact with shale bedrock. At its deepest, the cave is under 750 feet of limestone. It is one of the longest caves in the world.

Bill Balfour, who has mapped much of The Hole and much of the 400 miles of other mapped caverns in Greenbrier, helped introduce Boyer to the county's caves. Balfour is a volunteer with the West Virginia Association for Cave Studies, which helps researchers like Boyer.

"We have accumulated data over 30 years and can save cave explorers the years of work it takes to compile information on caves or karstic areas," Balfour says. "We give them maps, suggest likely water sampling spots, and delineate drainage basins for them, so they're not going in blind."

He believes that Boyer's work is "very important because it provides good baseline information on water quality in limestone bedrock areas." He notes that "a tremendous amount of the country is underlain by limestone. A lot of good pasture, good rolling farmland, lies over this limestone and many people draw their drinking water from holes in the limestone bedrock."

Not many people pump water from limestone in The Hole Basin, Balfour says, but more do toward the west of the Basin, where the bedrock becomes thicker and it's harder to drill through to shale or sandstone.

Greenbrier County sits in the middle of the Appalachian Karst, a topography that results from the work of underground water on limestone bedrock, Balfour says. Karst comes from the German kras, which refers to the bleak, rocky limestone found in coastal areas in the former Yugoslavia.

The major U.S. karstic areas occur in Kentucky, Indiana, Missouri, eastern Kansas, Oklahoma, northeast Iowa, Wisconsin, other parts of Appalachia, and Florida.

Even though the large, dramatic karstic topography is limited to these areas, there are caves in just about every state in the country, Balfour says.

The Karst Plateau in Appalachia is hardly stark, Boyer says. It is actually the most lush land to be found in that mountainous region of acid soils. The gentler limestone terrain and soil characteristics make it a more hospitable place for grass.

Native Americans learned this and expanded grasslands in the area for buffalo pasture by burning forests down, Boyer says. Now the area is called The Great Savannah.

The Savannah grass makes it hard for the casual observer to distinguish sinkholes from river valleys.

What's Above Affects What's

Below

In the Hole of the Devil, Boyer and Hall are deep under a farmstead. They stop to look at a section of the farm's well casing, a 6-inch metal tube inserted about 200 feet down for drinking water. When they return to the surface, they can see the windmill that pumps the water.

About 5 feet of the well casing's length is exposed momentarily in one of the passageways carved by Adjacent Stream. The well goes down below The Hole and draws from the shale layer beneath the cave floor. Once, they persuaded the farmer to join them on a 3-hour journey to the well and back.

The farmer's decision to draw water from beneath the cave was wise, Boyer says. His samplings of cave water and springs for the past 2 years have convinced him not to drink the water. Besides nitrate, he samples for atrazine and related herbicides used to control weeds in cornfields.

He also samples for two kinds of fecal bacteria. When a high bacteria count coincides with a high nitrate measurement, Boyer believes the nitrate came from manure rather than commercial fertilizer or a natural source.

If Boyer has any doubts, after leaving the cave, he can drive his truck around the farm and see if there are cows above that part of The Hole.

While bats turn their upside-down heads slowly in his direction - trying, perhaps, to decide if it's time to wake up and fly away - Boyer uses a syringe to collect beads of water that decorate the cave ceiling like little pendant jewels under the artificial light.

He's invariably found high levels of nitrate in these drops. Boyer believes that natural soil bacteria in the cave are forming the nitrate by oxidizing ammonia when it enters the cave air. He plans to conduct experiments to check on this theory. Like nitrate, the ammonia can come from commercial fertilizer, manure, or natural sources.

Boyer's journey today ended at The Maze, just below the sinkhole that feeds South Maze Stream, barely a half mile's journey. The one-way trip took about an hour and a half.

Boyer calls this part of South Maze Stream either Black Stream or Brown Stream, depending on how much biological ooze it contains on a particular day.

In it and its tributaries, Boyer has found average nitrate levels of 80 parts per million (ppm), accompanied by an excessive fecal coliform bacterial count of 10,000 colonies per hundred milliliters. U.S. Environmental Protection Agency guidelines for nitrate levels in drinking water call for a maximum of 45 ppm.

Boyer explains the reason for the drinking water guidelines: "Nitrate can cause blue baby syndrome in infants and can kill them at 300 ppm. When water is boiled as it is for infant formula, nitrate is left behind as water evaporates. With initial nitrate levels above 45 ppm, the boiled water could concentrate levels to 300 ppm or more. Also, nitrate - like nitrite which some people avoid eating because of health concerns - can convert to carcinogenic compounds, under certain conditions.

"You don't see levels anywhere near 80 ppm in the springs that emerge from these caves, because they are diluted by cleaner water before they emerge," Boyer says. "But we can sample the water under each different land use and discern the effects from that one land use." All he has to do is crawl around underground until he reaches the cavern directly below the suspect site.

Boyer explains that over the years, sinkholes have been seen as convenient dumping places by people unaware of their role as funnels to caves. State law forbids dumping objects but not agricultural waste into the sinkholes.

Lloyd Burns, a farmer who calls Boyer whenever he finds a hole in his fields, taught Boyer another reason farmers used to fill sinkholes. Burns has a 258-acre cattle farm in the rolling hills of Greenbrier County, above several other caves that Boyer has also sampled.

Burns told Boyer he grew up with the story of how one of his father's cows slipped through a sinkhole opening in the 1920's, falling 50 feet down. His parents often took him to the opening and told how his father, Sully, was lowered into the sinkhole by his neighbors and a team of horses. Sully tied the cow to a harness and had the team of horses pull the cow back up. Then his neighbors lowered a rope for Sully to escape as well.

The cow was unhurt, her fall cushioned by deep, thick mud at the bottom of the sinkhole. She survived to become pregnant and give birth to healthy twins.

Burns didn't realize he'd get to see his father in action again. When he was 6 years old, he went to feed some calves and noticed two missing. He knew where to check: Sure enough, Sully had to perform his legendary feat again, lowering himself by rope into the sinkhole and emerging with the help of horses.

That was the last straw for Sully. He filled the sinkhole with old fence wire and put a fence around it.

Boyer persuaded Burns to reopen the sinkhole so he and other cavers could explore it. Burns, Boyer, and several Boy Scouts removed enough debris to warrant a few trips to the landfill.

Boyer takes water samples on the Burns farm at least once a week; daily, after a heavy rain.

Burns says he is constantly on the lookout for agricultural pollution problems so he can do his part to stop a problem before it gets big. "I'm the last person to want pollution. I get my water from wells and would be totally helpless without it."

"I hope there won't be excessive regulations on agriculture - only needed ones," he adds. "I believe the truth about agricultural pollution is somewhere between what is said by extremists on both sides of the issue. Still, we can't continue to mess up the land, throw trash on it. I'm concerned about keeping the Greenbrier River pure and clean."

Tracing the Green Stream

Boyer is currently timing the flow of water through sinkholes by having colleagues flush hundreds of gallons of green-dyed water down each sinkhole. He has them wait 2 hours after he enters a cave, to give him time to reach the stream below the sinkhole.

When it rains hard enough to flush the dye down, Boyer checks to see how long it takes before the dye appears in a surface spring. He uses the dye, which is harmless, to confirm hydraulic connections, such as whether a particular sinkhole feeds a certain cave stream far beyond The Hole's South Maze Stream. He has traced waterflow through "bits and pieces of caves" to a spring on the Burns farm.

Boyer double-checks the dye connections by traveling through caves with a compass, measuring tape, and inclinometer to locate himself with respect to the surface by checking direction and angle of incline.

"We study waterflow through limestone because that's the route agrichemicals also take," Boyer says. "Pollutants can travel much faster and in different directions in caves, compared to other topographies."

While he doesn't see widespread agricultural problems so far, Boyer says it is important to monitor spring and cave water so nitrate doesn't get into groundwater.

Furthermore, "The accurate mapping of these underground drainage patterns will help the Soil Conservation Service work with farmers to develop farm management plans and practices that minimize the possibility of groundwater pollution."

Beckley: The Town With a Mine

of Its Own

You can't spend even a day in Beckley, West Virginia, without getting an urge to go underground.

Fortunately, as the town's slogan implies, the town obligingly offers daily visits to an old coal mine.

About a half mile from Beckley's airport, the National Mine Health and Safety Academy nestles in mountainous woodland across the street from the ARS Appalachian Soil and Water Conservation Research Laboratory. The lab sits on 43 acres of similarly rugged terrain.

The academy addresses all mining safety-related activities throughout the United States. And although the ARS lab itself covers only the 121-million-acre Appalachian Region, it links to other ARS labs nationwide and is becoming an international authority on acid soils.

Even the academy's hotel and classroom buildings have a decidedly underground feel, with low lighting, exposed girders, and photos of mines.

The ARS lab opened in Beckley in 1980, to research reclamation of the acid soils of abandoned stripmined areas. Its mission has expanded over the years to focus on farmland soils that are naturally acidic and infertile.

The lab has always had a water quality mission, beginning with studying the effects of runoff from abandoned mines. Now its role in USDA'S Water Quality Initiative has brought it into the area of natural caverns as well. Fortunately, these "mines" are much more structurally stable than coal mines, because underground rivers like the Shale River have eroded all the weak layers and left mostly solid shale below and thick limestone above.
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Title Annotation:includes related article on Beckley, West Virginia
Author:Comis, Don
Publication:Agricultural Research
Article Type:Cover Story
Date:Aug 1, 1993
Words:3079
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