Water: It’s all around us. So, why so many issues finding enough and utilizing it for hydraulic fracturing? AAPG member Dan Arthur shares his insight into water sourcing for this widely-used process for oil production.
Water issues are becoming an increasingly large concern throughout the industry – and geologists are becoming an increasingly important part of cautionary concerns. Photos courtesy of Dan Arthur
With almost three-quarters of the earth’s surface covered in water, finding enough for drilling procedures seems simple.
But not so.
“Water can be a huge issue,” according to AAPG member Dan Arthur of Tulsa-based ALL Consulting, which works on strategic issues in developing conventional and unconventional resources.
For the past two decades, Arthur said, water has been the main focus.
With hydraulic fracturing becoming increasingly integral to production, water issues well up at every step of the process, he said.
In some plays, finding a suitable source is key. In other plays, disposal, treatment, storage, transportation or quality may be driving issues.
Water sourcing varies depending on the character of plays worldwide, Arthur said.
“Look at China – a lot of shale resources are in areas with little water,” he said. “It may take 5-10 million gallons of water per well, but China is in desertification.”
In Canada, meanwhile, there is a lot of pressure not to impact surface water protected by First Nations’ (native populations) rights.
There, companies like Apache and Encana strip souring acids from ground water, use it in hydraulic fracturing, then dispose of it in the formation of origin, Arthur said.
In the Marcellus and Pennsylvania shales, “There is a lot of rain, but a lot of demands on the water, and it is tightly controlled. There is limited disposal,” Arthur said.
“In the Utica (in Ohio), instead of disposal wells, companies look at treatment and 100 percent reuse of the water,” he said.
“We started using models in the late ‘90s – how much is needed to drill the well versus water costs versus production plus disposal – what the drivers are depending on what play you’re in,” he said.
“It’s not just a matter of, ‘I have this water. Do I use it?’ You can’t just get water from the creek or a ground well. You may need a large impoundment and time to permit it. There are a lot of choices involved.
“If Company A is in the Eagle Ford with 11 or 12 wells running, they want a lot of things done fast,” he said. “Company B may have 30 or more – a lot of planning has to fall into place.”
Having an Effective Plan
People tend to think “water is just water,” Arthur said, “but quality before and after use are other complicating issues.”
Source water may contain chemicals, contaminants or bacteria that may affect its efficiency in hydraulic fracturing, he said.
Some sources may require more pre-treatment of the water.
In some cases, “If we ‘engineer,’ or blend a water, using what’s already there, we may need to add fewer chemicals for fracing. By modeling this in advance, we may save hundreds of thousands of dollars per job,” he said.
“You need an effective plan – a water life-cycle management planning process. Sourcing, storage, transport, distance all figure in,” he said.
“If you reduce water costs in the Eagle Ford from, say, $8 to $3 a barrel, you might save a half-million dollars per well. It’s not something you can ignore.
“People say we have enough oil and gas for another 100 years. You’re talking one-to-three three million wells over time in the U.S., if that’s true.
“It means a lot for the business,” he added. “There are a lot of big problems to be solved and a key component is water. No water, no development.”