The deeper that the Permian Basin enters into the current expansion, the greater the role that water plays in the overall dynamic. Whether the question is supply, or conservation, or treatment, or disposal, water issues are a rising tide. Understanding the “water cycle” is a key to keeping the tap turned on. By Al Pickett, special contributor
As Permian Basin operators turn the drill bit on its side and drill more horizontal wells with longer laterals, the need for even more water to be used in large hydraulic fracturing jobs increases just that much more. Thus, the cost of finding new water sources as well as either disposing or recycling produced or flowback water has become a major economic issue for the oil and gas industry.
Enrique Proano, vice president of Water Management Solutions, calls it the “water cycle.” Water Management Solutions is a service line of Cudd Energy Services, a division of RPC, Inc. Cudd’s corporate headquarters are located in The Woodlands, Texas, but the firm also maintains offices in Midland.
“Cudd wants to be a provider of water management,” Proano said, citing some other steps as being equally important in managing the “water cycle”: finding sources of water; transferring or moving the water; storing, conditioning, and treating the water; application services; flowback services; and, finally, disposal or recycling.
While water management issues are an increasingly important part of the oil and gas production story, water has become so much more than just a vital element of an operator’s economic equation. Set against the backdrop of the continuing drought in the Permian Basin and all across the state of Texas, water is now a critical public relations and environmental issue for the oil and gas industry.
As the booming oil and gas industry in the Permian Basin continues to grow, where is the industry—and the region, for that matter—going to find enough water? How serious is the current drought? Can the abundant brackish groundwater found in the Permian Basin be used in hydraulic fracturing? What technological advances are being made in treating flowback or produced water? A number of experts in the industry, from consulting engineers to water management/water treatment companies, addressed those and other questions related to water for Permian Basin Oil and Gas magazine.
Drought Impact
The current dry spell is increasingly compared to the severe drought of the 1950s, a period that inspired the bestselling novel The Time It Never Rained by Elmer Kelton, the celebrated western writer from San Angelo, now deceased.
“Devastating droughts in Texas have typically occurred when below-average rainfall conditions persist for a long period of time,” explained Barney Austin, Phd., who is a professional engineer and director of hydrologic services for INTERA, a leading geosciences and engineering consulting firm in Austin. “In the 1950s, the Midland-Odessa region experienced below-average rainfall for six consecutive years [1950-56], including an extremely dry year [1951] when there was less than five inches of rain.
“What has hurt the Midland-Odessa area so badly recently is the occurrence of back-to-back droughts in the late 1990s and early part of this century. The region experienced six years in a row with less-than-average rainfall (1998-2003). After a brief but fairly wet spell (2004-07), we are now in the seventh year of another drought—if you include 2009 and 2010, when average rainfall occurred but soil moisture conditions didn’t really recover—including one of the hottest and driest years on record in 2011. Unfortunately, the folks at the National Oceanic and Atmospheric Administration’s Drought Prediction Center expect the current drought to continue in the short term. The real concern is that we don’t know how long this drought will continue. Some people speculate this is the new normal.”
While the large amount of water used by the oil and gas industry is often cited by environmentalists in their attacks on hydraulic fracturing, Gerry Grisak, senior vice president and principal hydrogeologist with INTERA, observed that the amount of water used by the industry is miniscule in the larger picture of the state’s water usage.
“Water use in relatively large hydraulic fracturing campaigns is often cited at about one to three million gallons [or about three to nine acre feet] per well,” Grisak stated. “In 2011, the total amount of water used by hydraulic fracturing across Texas was about 0.08 million acre feet, or about one-half of one percent of the total water use in Texas of about 18 million acre feet. Annual municipal water use in Texas is about 4.8 million acre feet, and annual agricultural water use is about 10.1 million acre feet.”
Grisak acknowledged that the percent of water used by hydraulic fracturing can be more significant on a local basis, sometimes as much as 20 percent of the total water use in a county. Recognizing the competing interests for fresh water (including fresh groundwater), the Texas Bureau of Economic Geology in a recent report distinguished between water use and water consumption.
“Water use is the total amount of water used in hydraulic fracturing operations,” he explained, “whereas water consumption is the total amount of fresh water, not including brackish groundwater, reuse of flowback water, and recycling from other oil and gas industry operations. Across all of Texas, brackish water/recycled water is currently about 21 percent of water used for hydraulic fracturing. In the Permian Basin, the percentage of brackish water used in hydraulic fracturing is currently somewhat higher. In the period of 2020-2040, brackish water is predicted to be 60 to 75 percent of the total amount of water used for hydraulic fracturing.”
Groundwater Database
Last summer, INTERA released the first comprehensive complementary database of groundwater resources in Midland County. The new database included aquifer locations and depths; well yields, locations, and water quality; water-level trends; cross-sections from geophysical log correlation and disposal well detail. It also provided an in-depth summary of Midland County’s fresh and brackish water source options and characteristics.
“The main purpose of the study was to compile all available sources in a format that is easily digestible,” said Wade Oliver, a hydrogeologist with INTERA. “We have done a lot of confidential studies for companies, but we did this study on our own dime that we made public.”
Grisak said INTERA took a cross section of Midland County from southwest to northeast to demonstrate the quality of the Santa Rosa, a brackish water aquifer that lies below the county’s fresh water sources. He pointed out that the freshwater aquifers in Midland County, the Ogalalla and Edwards-Trinity (Plateau), lie about 100 to 300 feet below the surface, while the Dockum zone, which has the Santa Rosa at its base, is at about 1,200 feet depth.
“We developed a methodology and used existing geophysical logs to go through a series of steps to be able to ascertain the water quality in the Santa Rosa,” he explained.
The quality of Santa Rosa water varies from one end of the county to the other, according to Grisak. He said the water in the Santa Rosa in the southwest portion of Midland County is not potable, but is “pretty good.” As the aquifer moves northeast, however, it becomes very salty. Oliver said salinity levels of Santa Rosa water can vary from 2,000 to 3,000 parts per million to 50,000 parts per million from one end of the county to the other.
INTERA’s published study not only demonstrates how water quality varies from one part of the Permian Basin to another but also provides interested parties information related to different types of water.
“The formula is different for every well,” Grisak replied when asked about the possibility of using more brackish water in hydraulic fracturing. “But the scarcity of fresh water in the Permian Basin is a big deal with the current drought. I can’t tell you how much brackish water there is in West Texas and southeastern New Mexico, but I think we will see a continued growth in the use and application of brackish water, and as well alternative fresh water sources, for the next 30 to 50 years. Cities in West Texas will be adding groundwater as part of their water portfolio in the next century.”
Grisak said INTERA’s role is to identify water sources, but each oil and gas operator in the Permian Basin has its own issues related to the quality of water it can use. One of the problems in obtaining the Santa Rosa water, according to Oliver, is that the deeper brackish water zones are less prolific than the shallower fresh water zones, so, as Oliver put it, “installing [water] well fields is a little more involved.”
“You have to decide whether you are willing to make an investment up front,” Grisak added. “Recent research by many firms has demonstrated that hydraulic fracturing can be accomplished with a broad range of water quality. The primary constraints, which contribute to scaling and the concomitant reduction in productivity, are microbiological action and precipitation related to the chemical constituents in the water. Research on all of these issues is advancing rapidly, with month-to-month changes and improvements in water quality constraints reported in the literature.”
Desalination of groundwater is another issue. Grisak said the El Paso is using desalination with its Kay Bailey Hutchinson plant to produce water for the city. He added that INTERA contributed to a request for a proposal by Odessa to desalinate deep Capitan water from Ward County for that city’s drinking water.
Water Management
According to Proano, Cudd Energy Services offers a number of different water management services, including its Atlas SMARTank technology, which remotely delivers tank level data in real time for improved safety and maximized efficiency.
The SMARTank Technology is utilized in intra-field water transfer applications, which, as Proano says, “is a safety measure because it eliminates the need for workers to walk on top of tanks to monitor water levels.”
The technology also helps operators manage water levels and pump rates with real-time data to maximum tank efficiency, according to Proano. Tank level data can be conveniently accessed through a secure network onsite via a personal computer or mobile device. “When companies are transferring water into multiple frac tanks, it is impossible,” Proano said, “to fill the tanks at the same rate.
“Our system has a series of manifolds so you can choke back if you need to,” he explained. “The Atlas technology gives you a visual display so you can very accurately calculate flow rates. It is more than just safety. It has been very well received.”
Besides tank and water level monitoring, Cudd provides other systems for the entire water management operation. Proano stated that 100 percent of the water used in hydraulic fracturing—even fresh water—has to be conditioned. Usually it is treated with a biocide to prevent bacteria in the reservoir. Often solids or certain impurities found in fresh water must be removed.
“A sour reservoir,” or one with hydrogen sulfide gas [H2S], “could reduce the value of reserves,” he said. “Acidizing can create a huge corrosion issue. Accumulated biomass can clog up the production string. People spend a lot of money trying to correct problems that could be prevented with minimum water conditioning. Scale inhibition and desalination are big issues, too.”
The development of new additives, or frac fluids, by companies like Cudd has made a big difference in the quality of water that can be used for hydraulic fracturing.
“As frac fluid technology has advanced, the quality of water that can be used is lowered,” Proano said. “You don’t need pure water. That is no longer a main driver.”
The use of brackish water or recycled flowback water is the future of the oil and gas industry because, as Proano asserted, it offers significant cost savings.
“Environmental stewardship is also important,” he said, adding that the industry must “find ways to minimize the use of fresh water.”
Proano says that roughly 75 percent of the cost in the water cycle is dedicated to trucking water and disposing of the produced water. By recycling, companies can avoid disposal costs and save money.
“For example,” he explained, “if it takes 100,000 barrels of water for a frac job, you usually get about 30 percent, or 30,000 barrels, of flowback water. At $15 a barrel to truck [the 30,000 barrels] to a disposal well, that [cost] is $450,000—a huge sum.”
More and more companies are choosing to recycle flowback water, allowing that water to become a source again.
“The savings cost is a huge part of the equation,” Proano said. “In the last five or six years, a lot of players are developing technology for water treatment and recycling. The industry is still in flux, trying to keep pace with the shale boom. As fields mature, it will change the dynamics.”
While some operators are proactive and are recycling as much as 50 percent of their flowback water, Proano estimates that probably less than 10 percent of the produced water in the Permian Basin is currently being treated and recycled. He said that understanding frac fluids gives his company significant insight [in water management].
Treating Water
Midland-based Water Cleaning Services uses three different methods of treating brackish well water, as well as flowback and produced water. Brent Clinklaw, operations manager for Water Cleaning Services, listed back filtration, electrocoagulation, and reverse osmosis as methods it uses to treat water.
“Back filtration is the least expensive,” he offered. “It removes solids from the water. We see it a lot with coiled tubing and drill outs when they want to reuse the water.”
Electrocoagulation is used to treat flowback water, Clinklaw continued.
“It is used to remove suspended solids and iron and heavy metal reduction,” he said. “It reduces H2S. It produces a clean brine for re-use.
“Reverse osmosis is used to get back to pure water. In the Permian Basin, for example, the water wells west of the Pecos River are high in sulfate and total hardness. Reverse osmosis is used to remove hardness and sulfate.”
Clinklaw said more and more operators are looking for way to reuse water because it saves on trucking costs.
“If you look at the total life cycle of a barrel of water,” he emphasized, “it is a less expensive alternative to treat and recycle flowback water. The drought has played a part, too. The Railroad Commission is making it easier for operators by loosening up restrictions on salt water pits.”
Making water treatment technology more cost effective and having the foresight to project where the market will go in the future is a lot like hitting a moving target, according to Cudd’s Proano.
“You have to aim ahead of it,” he said.
But that is the challenge today for operators in the drought-stricken Permian Basin, where water conservation is crucial and water management is becoming an increasingly important part of the oil and gas industry’s overall production and completion picture.
Al Pickett is a freelance writer in Abilene and author of four books. He also owns the West Central Texas Oil Activity Index, a daily and weekly oil and gas reporting service. For more information, e-mail apickettc@sbcglobal.net.