Wink sinkhole center of speculation among residents Gary O. Midland Reporter Telegram 08/11/2002 http://www.mywesttexas.com/ By Stephanie Sparkman MRT Correspondent WINK -- No one knows for sure what's causing the ground near Wink to be swallowed up, but speculation abounds. When the first sinkhole appeared on the morning of June 3, 1980 approximately two and a half miles northeast of Wink, just south of Texas Highway 115, it was a novelty to residents of the area and, although the ground around the hole was unstable, teenagers used to sneak past the fence surrounding it to swim in the pool it formed. The Wink Sink, as it came to be known, was the source of media attention from around the country as news crews converged on Winkler County to report on the phenomenon, which geologists from the University of Texas at Austin concluded was more than twice the volume of another evidently famous sinkhole in Barton County, Kan. The main concern for many residents of the area, however, was whether they had to worry about their own land disappearing into a hole. As years went by without other sinkholes forming, their insecurities subsided. Then, on May 21 of this year, about a mile from the original sink, the ground opened up again, gobbling up more earth and rekindling old fears. "We're all wondering if we're all going to sink," said Caroline Harrison of Kermit. "It's (the new sinkhole) about six miles from our house, but with them coming up like this, you never know." According to Mrs. Harrison, the ground surrounding Wink and Kermit was slush when she first moved to the area. "When I moved to Kermit in 1959, all of that was just slush between Wink and Kermit," she said. "It was all on top of the ground, pools of water. Just about everything west of Wink was also that way. You don't know where one (sinkhole) is going to come up next since all of this was oilfield at one time. "They pumped salt water all out from underground," Mrs. Harrison added. "A lot of people think the cavities were caused by that. That field where these (sinkholes) are is where the first oil wells in Winkler County were. Hendricks Field. The oilfield is all the way around us -- it's circling us." Having their land disappear from underneath them is not the only concern of some Wink and Kermit residents. The stability of the highway that links the two towns is also a concern. "A rancher told me a couple of years ago that the highway between here and Wink (Texas highway 115) has a big crack in it," Mrs. Harrison said. "They just keep filling it in so not a whole lot of people know about it, but I'm a lot more cautious about driving on it since this second one opened up." Although the formation of the second sinkhole, which is larger and deeper than the first, has many wondering about when and where future sinkholes might form, life in Winkler County goes on. "We're not sitting around here, holding our breath, worrying about it," Mrs. Harrison said. "It's just something we live with day to day. But, there's not a day that goes by that somebody doesn't bring it up." Pauline Kline, of Wink, doesn't worry a lot of the second sinkhole, but concedes there's a lot of speculation about what caused it. "I don't think a lot about it because I haven't seen it yet," Ms. Kline said. "There's been a lot of oil taken out of here. Some people think it's connected to that. Some people think it might even be connected to Carlsbad Caverns." Geologists with Devon Energy, Inc., the landowner, don't think the formation of either sinkhole was connected to oilfield production. Although Devon Energy owns the land where the second sinkhole formed, the company does not have any production on it. "Sinkholes are generally a naturally occurring phenomenon around the world in areas where there is shallow limestone and/or salt deposits, both soluble in water," said Vince White, vice president of corporate communications and investor relations. "Of all the sinkholes in the world, almost all do NOT have anything to do with oil field production." According to the U.S. Geological Survey's Water Science for Schools Web site, sinkholes are found in areas where the rock below the land surface can naturally be dissolved by ground water circulating through them. The site goes on to say, "As the rock dissolves, spaces and caverns develop underground. Sinkholes are dramatic because the land usually stays intact for a while until the underground spaces just get too big. If there is not enough support for the land above the spaces then a sudden collapse of the land surface can occur.'' The most damage from sinkholes, according to the USGS site, have occurred in Florida, Texas, Alabama, Missouri, Kentucky, Tennessee and Pennsylvania. Ernie Baker, hydrologist emeritus for the USGS Austin office, was unaware of the formation of the second sinkhole in Winkler County when contacted by the Reporter-Telegram. After taking information and studying maps and old reports Baker concluded, "The culprit is a formation in the Delaware Basin called the Salado Formation. "The Salado Formation has salt and gypsum beds in it that are subject to dissolution by water that may contact them," Baker said. "Dissolution of salt has caused the sink. The salt and gypsum have been dissolving for millions of years. This is an example of land surface collapse and subsidence caused by dissolution." When comparing the locations of both sinkholes, Baker thinks he sees a definite correlation between the two. "It appears both the No. 1 and No. 2 holes are both appearing above the Capitan Reef which is not very wide but extends through Brewster, Pecos, Ward and Winkler counties of Texas and up into New Mexico," Baker said. "The Salado Formation is a wide salt bed with sandstone and shale and it's scattered everywhere out there. But, you have to have something causing this collapse, which is above the narrow band of the Capitan Reef and below the Salado. Evidence points toward the Capitan being instrumental in some way.'' According to Baker, the Capitan Reef is present under both sinks and runs in a band several miles wide from New Mexico, around the Carlsbad area, to where it surfaces in the Guadalupe and Apache Mountains to the West of Winkler County. Devon Energy geologists do not believe the Capitan Reef has anything to do with the sinkhole. According to White, Devon's geologists believe "the formation of the sinkholes has something to do with a fault trend that runs through the area, allowing water a path down to karsted areas below the earth's surface." The American Heritage Dictionary defines a karst as "an area of irregular limestone in which erosion has produced fissures, sinkholes, underground streams and caverns." David Powers, a local consulting geologist who is not connected with Devon Energies, agreed the Wink sinkholes are naturally occurring and not connected with oil production. "Most people think oil is under the ground in big pools, like a gigantic oil tank," Powers said. "That's not the way it is. You get oil from little tiny microscopic pores. You don't have big caverns underneath the earth that are filled with oil. When the oil company is taking oil out of the ground, it's not leaving a big hole under the ground. "Sinkholes are the result of the weathering of rock that has been going on forever," Powers added. "It's been going on longer than anything that's out there -- longer than anyone's lived out there, longer than there's been oil production out there.'' However, there is some question as to whether or not waterflood projects, which began in the Hendrick Field in 1963 and are still in progress, might have something to do with accelerating the dissolution of salt beds in the Salado Formation. In an official Bureau of Economic Geology report for the University of Texas at Austin, after studying the first sinkhole in 1980, geologists Robert W. Gaumgardner Jr., Ann D. Hoadley and Arthur G. Goldstein concluded "dissolution of salt in the Permian Salado Formation is inferred to have produced the solution cavity" ultimately caused the collapse of surface ground, forming the sinkhole. The report further states a possible explanation for dissolution of the salt in the Salado Formation may be the movement of water upward through artesian pressure from water below the formation and downward under gravity from aquifers above the formation. Additionally, the UT geologists concluded, "A plugged and abandoned well that was located within the circumference of the sinkhole may have provided a conduit for water movement." According to the report, that well was the Hendrick Well number 10-A, which was drilled in 1928 and plugged with cement and abandoned in 1964. "Over 12 million barrels of salt water produced from the Hendrick Field were disposed of by injection into the Permian Rustler Formation during 1961," the geologists wrote. While it is certainly possible corroded, damaged casing from plugged wells could cause water from injection projects to go out into the Salado and dissolve salt causing caverns, experts agree proving it would be a difficult task. Whether or not the exact cause of the Wink sinks is ever determined, the most important question for residents like Charlene Beatty Beauchamp is safety. "I remember when the first sinkhole started," Ms. Beauchamp said. "It was a big concern then because no one had ever seen one. The teen-agers used to go swimming in it. This one is kind of old hat. "But, if more form closer to town, it might be more of a concern because of kids wanting to play out there and things," she added. "The ground is still real unstable at the new site. The oil company has done what they can to keep people away. They put the fence around it and won't allow anyone in. Before the fence was put up they had people guarding it to keep people away." According to White, safety is the Devon Energy's primary concern as well. "Safety is our number one concern," White said. "We want to discourage any curious people from crossing the fenced area of this sinkhole -- or from any other sinkholes. The ground around this sinkhole, especially, is still very unstable." As far as fear of being swallowed up by a sinkhole is concerned, White said residents of the area should not panic. "There are a lot of remote things that can affect you," White said. "The odds are remote that you're going to be affected by a sinkhole. There is no cause for panic. The possibility that your home is going to fall into a karst is remote."