Water management: Under pressure
MARK PATTON, CONTRIBUTING EDITOR
Although not my favorite David Bowie song, “Under Pressure” really does reflect Produced Water Management today. Most people would agree the seismicity issue is probably on the top of the list when it comes to the complexity of managing produced water.
But there is a new concern that has been on the rise, maybe not new but at least getting a lot more attention lately, and that is the well blowout. The abandonment of old wells has always been an issue, but we are seeing with this concern large, and continuous, leaks of produced water.
Handling over-pressurization. Surface leaks can also be a significant threat to groundwater. Over the past few years, these incidents seem to me to be more and more commonplace. Just a few weeks ago, a produced water geyser appeared near Pecos, Texas. Now, I must be fair, these could be formation water leaks and not produced water from disposal zones, but let’s talk a little background before we go further.
In the Midland basin of the Permian basin, we have long understood that the San Andres formation is over-pressurized. After a few years of operators urging for alternatives, the practice of drilling deeper disposal wells beneath the San Andres became a more common practice. Well, a while after this practice began, we started to see a rise in seismicity. I’m not implying this caused the seismicity, but after investigations into seismicity started, it was determined that these deeper wells were the primary contributor to seismicity.
So, at least the reduction, or elimination, of produced water capacity became the primary objective of the strategy to combat seismicity. Understand that reducing capacity or eliminating capacity redirected this capacity back to the shallower and more over-pressurized San Andres.
Solving produced water blowouts. While this occurs, we hear reports of more and more blowouts of produced water. Now, in all fairness, well blowouts have always been a problem, and without concrete data supporting an increase in these blowouts, the two events may not be related. Is there more attention being paid to these events than before, is social media causing an increase in the reporting of these events, or are they really occurring at in increased frequency? I can’t answer these questions.
Additionally, this blowout problem is not unique to the Midland basin; many of these events reported lately are in the Delaware basin and may not be impacted at all by the San Andres over-pressurization problem. Are there well communication issues, where the pressure is migrating and leaking into these abandoned and plugged wells that, because of their age ,are decaying or maybe weren’t properly abandoned in the first place?
Regardless, this is a problem that requires our immediate attention. It is irrelevant whether the problem is really over-reported or blown out of perception. I have had some people tell me that it’s part of the political cycle and, with people running for office, this is the issue they want to highlight. The problem is it is really happening. I have witnessed it, myself. I can’t attest to frequency, but it is real. We don’t need another public relations problem while we battle seismicity.
So, what do we do about it? Well, let’s start by inventorying our abandoned wells and begin a monitoring program that prevents these surprise geysers or just surface leaks. A small containment with leak detection isn’t that difficult and can prevent surface spills, at least those at the wells. Something I heard discussed lately is the use of extraction wells, where we extract produced water from these disposal zones and eliminate the use of brackish water. This could alleviate some of the pressure concerns, if they are contributing to the blowout problem. And this makes sense, because currently the primary option for produced water other than disposal is recycling.
But recycling has its challenges. Wells don’t typically produce water at the rate and location where they need it. When we talk recycling, we refer to the use of produced water as a completion fluid to complete wells. And over the years, we have seen the daily water needs and completion practices, as well, have changed from zipper fracs. And other multi-well fracs are causing a sharp increase in the daily volumes of completion fluid needed. Currently, the practice of using storage ponds has been utilized to aggregate water, to have enough to meet demand, but again with limits on how much produced water is generated at each producing well, this could take time. This is where extraction wells can help supplement the volume and increase the recycling of produced water.
Recycling has other challenges that we have discussed, like landowner restrictions or requiring the purchase of their water and the logistics of having the water in the right location. One challenge we haven’t discussed and is another form of pressure on produced water management is utilization. You see everybody in the produced water recycling business today having a utilization problem. The assets they use for recycling are seriously under-utilized, resulting in an erosion of their margins. Look at it this way —recycling infrastructure is built to supply a volume of water, but the demand for water isn’t constant and moves around, as frac activity moves around. In combination with this, you are competing against other people supplying recycled water and brackish water supply. So as frac activity moves, or you lose an opportunity, your asset sits idle, leading to underutilization. Even recycling companies in the business of portable recycling see this problem from either competing on contracts and losing to mobilizing, or waiting as the frac schedule changes and your equipment sits idle.
We have seen, over the years, recycling companies leave the market and expect this trend to continue. We also have talked to water midstreams, who refuse to chase these types of contracts, because they lead to underutilization. So, how do we solve this problem?
Moving water treatment upstream. I’ve had this discussion with many operators and midstreams, and there is a solution. Move water treatment upstream. And the further upstream, the better the results. By moving upstream, you increase the volume of water treated and, as a result, increase utilization, which decreases your cost per barrel. But wait, there’s more. I love saying that. You see your maintenance cost, in your gathering system and disposal wells, decrease, your oil recovery sharply increases, and cleaner water will decrease injectivity at disposal wells, meaning surface pressure will decrease, which should have an impact on reservoir pressure, which should help with decreasing seismicity.
Then there is emission reduction. A newer concern is emissions from produced water. New Mexico already has regulations in place, and the new EPA standards for methane also include produced water. Moving the treatment process upstream allows this emission to be managed upstream and reduced downstream, up to, and including, eliminating them with the right treatment strategy.
Now, would you be surprised, if I told you that an operator has already tried this, and the increase in oil cut, alone, paid for the extra treatment? So, this strategy more than pays for itself, but it has other benefits like your pretreatment costs for beneficial reuse or desalination are eliminated, making these practices more economically feasible.
So, yes, produced water management is under pressure, but there are solutions, and if there are solutions, there are opportunities. I continue to believe the “Holy Grail” for our industry is becoming water-positive, that is producing a new water source in produced water. And when we become the source of energy and water, we become one of the most sustainable industries around. Until next month, keep up the fight.
