Breaking into the Earth's Water Vault
Call them water scouts. Or sluice sleuths.
From the sky and from undergroundfrom satellite imagery to the depths of abandoned minesresearchers at UK's Kentucky Geological Survey (KGS) are working to find water to supply small communities in Eastern Kentucky.
Robert Andrews (left) and Jim Dinger are using remote-sensing devices and novel drilling techniques to find high-yield wells in Eastern Kentucky.
Is water really in such short supply in the eastern part of the state? Just recently, Kentucky's Division of Water listed all counties in Eastern Kentucky, except three bordering the Ohio River, as being under a water "watch" or "warning" with regard to water supply.
"In addition to shortages in municipal water supplies, many people in rural areas do not have adequate wells, or the water from their wells is high in iron content or sulfate that makes the water smell like rotten eggs," says Jim Dinger, the head of the Water Resources Section at KGS. "Some people are hauling in water to cisterns, which can be expensive and inconvenient. Others are going out with milk jugs and collecting water from roadside springs. This is obviously a health concern," he says.
One search-and-find mission, headed up by KGS geologists Dinger and Robert Andrews, involves using remote-sensing devices and novel drilling techniques to find areas of the Kentucky River Basin where high-yield wells can be drilled and ground-water supplies developed. Andrews is principal investigator on this High-Yield Water Project. The first two years of the study were funded by the University of Kentucky E.O. Robinson Trust; the project is currently funded by the Kentucky River Authority.
Dinger admits this is challenging work. "In other parts of Kentucky and the United States, large supplies of groundwater are found mostly in sandstone or gravel deposits hundreds of feet thick that extend for miles. These deposits act like huge sponges that soak up and store water. While the Eastern Kentucky Coal Field does have sandstone deposits, they are not hundreds of feet thick and don't go on for milesthese deposits are isolated on ridges that are separated from one another by intervening valleys," he explains.
The rocks of the Eastern Kentucky Coal Field, however, do have cracks and fractures in them connecting these sandstone deposits. These fracture zones act like drains and many contain large amounts of groundwater.
"What we're doing," says Dinger, "is trying to locate fractures that might provide sources of drinking water for small communities and towns in Eastern Kentucky." Even more important is to locate where these fractures cross one another, he adds, since this "crosshatching" means there's an even greater chance of finding large amounts of groundwater.
And this is where high-flying high-technology becomes a partner in this research.
"Examination of remote-sensed imagerysatellite images, low-altitude radar, and aerial photographsreveals what appear to be lines or, as we call them, lineaments," says Andrews. "Though these lineaments can represent roads and power lineseven railroad tracksthey can also represent vertical fractures in the earth's crust. In addition," he continues, "these lines can represent surface features caused by fractures. For example, straight-line stream valleys are generally formed in fracture zones." This technique of using remote-sensing imagery to locate high-yielding ground-water supplies was pioneered by Richard Parizek of Penn State University and has been successful in the United States and other parts of the world.
Utilizing satellite imagery, Andrews selects lineaments and, from a database accessible to KGS researchers, creates overlays of man-made features to distinguish them from natural lineaments. Armed with these maps and other information, Andrews and Dinger climb into a KGS truck and head into Eastern Kentucky to begin their reconnaissance mission.
"We need to actually see if we've identified the lineaments correctly," Andrews says. During their field-check, they look for road cutshillsides that have fractures. "Optimally, we're looking for long fracture zones in the earth's surface. These zones allow groundwater to move more quickly than it would through denser rock material."
Once the researchers are satisfied that the lineaments mark good, potential water sources, they decide which spot would most likely be best to drill. But Dinger is quick to point out that the actual drilling is contracted out. "You won't find us on a rig anytime soon," Dinger says, adding, however, that their supervisory role does not end here.
"In the past few years, we've adopted a drilling technique called inclined drilling, which has been very successful," he says. Instead of the traditional approachdrilling straight down into the earth and hoping to hit a fracture that contains waterinclined drilling gives more of a cross section of information about the nature of the bedrock, maximizing the chance that the drillers will find a fracture with abundant groundwater.
"With inclined drilling," Andrews says, "we drill a hole around 250 feet down at a 40-degree angle from the land surface to see if we can find water-producing fractures. This hole covers about 190 lateral feet of the subsurface. Then we drill a traditional, vertical water well at the location of the fracture."
Finding water is a good start, Andrews says, but there also has to be a large enough volume to make the work worthwhile. "We hope to drill a well that will yield greater than 50 gallons a minute, which would be enough to supply water to at least a small community," he says.
So far in this project, Andrews and Dinger have supervised drilling at eight sites in Eastern Kentucky with, as Dinger puts it, "quite a range of results." At their first site, the Hitchens community in Carter County, the well produced only 3.5 gallons per minute, barely enough for one home; but it was drilled without using inclined drilling. The Oakdale site in Breathitt County, however, was another story. The researchers identified lineaments and the drillers went to work. Using inclined drilling, they drilled a well that yielded nearly 98,000 gallons of water a day, greater than 99 percent of already-established wells in Breathitt County.
"This was exciting and very rewarding," Dinger says, adding that the researchers have chalked up similar successes in Clay, Knott and Letcher counties.
So, what's next?
Dinger explains that after the various water samples are tested back in KGS labs, it's up to the communities near these various sites to take it from there.
"The next step would be for the community to build a treatment plant close to one of these high-yield wells so the water can meet EPA standards," Dinger says. "With the good quality of groundwater we've been finding, this generally means that chlorination needs to be added to protect against bacteria." In the meantime, KGS researchers are continuing to refine their use of remote sensing and drilling techniques to locate fractures and large supplies of groundwater in the Kentucky River Basin, and they hope to extend this technique across the state to all communities short on water.
"Because these techniques continue to lead us to significant amounts of groundwater in Eastern Kentucky," Dinger says, "the survey has already conducted a workshop to teach these techniques to consultants who could apply them to other towns and communities in the Commonwealth."
Mining for Water
In a related project also funded by the Kentucky River Authority, KGS geologist Dennis Cumbie is working, too, to bring water to seven counties in the upper Kentucky River basin in Eastern Kentucky. In this steep terrain where adequate surface-water supplies are limited, Cumbie is looking for groundwater that has accumulated in abandoned, underground coal mines that may supply large quantities of water.
Dennis Cumbie says that abandoned mines are natural storage basins for water. The challenge: How best to get the water out.
"The problem here is that no water flows into Letcher Countyall the water just dribbles away to other counties," says Carroll Smith, Letcher County judge executive. "We've got the north fork of the Kentucky River, the Cumberland River and one of the forks of the Big Sandy River starting in this county, so as soon as it stops raining, the level of water in the rivers starts falling. In dry weather, from September to December, we get low on water, so the work Dennis Cumbie is doing out heretrying to determine the amount of water in abandoned coal minesis important for us."
But even if large reservoirs of water can be located, how safe and appealing would water be that has been infiltrated by coal dust for years?
"The water pumped out of the mines is surprisingly good," says Smith, who has held the judge executive position for the past seven years. "It's low in oxygen, as you'd expect since it's not exposed to the air, and most of the dissolved minerals in it are very treatable. The bacteria level and general cleanliness of the water are excellent. The KGS labs haven't found any heavy metals, which I was worried about early on." Cumbie says that the next step in the process, once the water quality is determined, will be to pipe or pump the water into the creek where it will naturally flow down to Whitesburg and Blackie where treatment plants are already located.
He admits that his work in Letcher and six other counties in Eastern Kentucky is in some ways easier than the challenges Dinger and Andrews face. "Mines are natural basins where water has already collected," says Cumbie. "I'm not pumping water out of rocks. Also these mines are huge. One mine in southern Perry County encloses several hundred acresfive feet in depth and 60 percent full of waterthat can equal hundreds of millions of gallons of water.
"Most things can be filtered out of water from mines. What you worry about in coal water are the things that are dissolved in it," Cumbie explains. Occasionally, this water can have high iron content, which is more of a nuisance than a health hazard, and it can be high in sulfate, which can cause the water to stink. "Though this isn't really a health problem, some of this water exceeds what the EPA calls 'esthetic standards.' This term refers mostly to odor and discoloration, iron being the main culprit. But these are problems that can be easily corrected with conventional treatment methods."
Since the general locations of the mines are well documented, Cumbie's biggest challenge, he says, is to try to figure out the best place to drill a well into the mine in order to maximize the amount of water tapped, or to find the locations where there is significant, natural outflow that can be captured for use. "I'm limited in my resources; I can't monitor every outflow in a huge mine, so I have to find as many outflows as I can, then prioritize," he explains. "I have to ask, 'Which outflows will be closest to the community that needs water?'"
Out in the field, Cumbie works with local coal operators, who take him to abandoned mines. "They know how much water they've had to pump out of mines; they know where water-filled areas should be," Cumbie says. He uses maps constructed from aerial photographs and tries to correlate the surface maps with sub-surface maps of the mine. "I select a site, then contract out drilling. I go with the drillers, hoping that one of several things won't go wrong," he says. "One danger, for example, is that they might drill into a coal pillar left in the mine instead of the space created by the mining activity."
So far, Cumbie is batting 1.000 in the drilling challenge. "We're three for three right now, our biggest 'strike' being the Polly Number 4 Mine, located at Cow Branch in Letcher County," he says. The estimated storage volume of this mine is 260 million gallons with a recharge rate of 450,000 gallons a day.
How common is it for a community to get its water from an abandoned mine?
"It's been done for years," Cumbie says. "It's very common in Pennsylvania, and in West Virginia, over 70 public systems get their water entirely out of underground mines." He says that the city of Welch, West Virginia, which is about the size of Jackson, Kentucky (population 3,000), gets all of its water from two underground mines. "The water is generally run through an aeration-filtration plant and is chlorinated. Then it's ready for public use." Two communities in Kentucky presently use similar systemsWheelwright in Floyd County and Fleming-Neon in Letcher County.
Although Cumbie is the primary UK contact for this project, he gets a lot of good help, he says. He consults with his colleagues at KGS and in the Kentucky Division of Water and the Kentucky Rural Water Association. KGS lab technicians analyze all water samples Cumbie brings back.
"I enjoy coming to work," he says. "I had never been around a coal-mining area until I started this job three years ago. This is important work, and it's rewarding to know you're helping the people in these communities."