May 2022 /// Vol 343 No. 5)
Water Management: The chicken and the egg
We all agree that the goal is to desalinate produced water to the point it can be reused beneficially, but there are many potential uses, each with its own inherent treatment requirements.
I recently attended the New Mexico Produced Water Research Consortium’s (NMPWRC) mid-year meeting at New Mexico State University in Las Cruces, N.M. What a great organization leading the charge on produced water research and regulation.
You may have read, in my previous columns, my discussions concerning New Mexico’s “Produced Water Act” and how it has helped increase produced water recycling. Well, this would not have been possible without the support of, and work being done at, the NMPWRC. But as the discussions and presentations amongst operators, regulators, environmental advocacy groups and treatment technology vendors continued, I realized we were creating a bit of a problem for our industry. We all agree that the goal is to desalinate produced water to the point it can be reused beneficially, but there are many potential uses, each with its own inherent treatment requirements. Additionally, you have regulatory hurdles with each potential reuse option, some more difficult than others. Then you have the issue of discharge standards and what those might be.
Treatment standards. In the meantime, you have technology suppliers developing treatment systems to reach a treatment goal that has yet to be defined. It’s like building a bridge to nowhere. Start building the bridge, and we’ll let you know later where it goes and how long it must be. Well, I am sorry, but we are creating a “chicken and the egg” problem. What comes first—the development of standards, so we can define the technology, or design a technology and hope someone agrees that it will create the standard? I’m beginning to understand why the desalination of produced water has not developed as quickly as people would have hoped. Five years ago, I thought we were five years away, but today we are at least another five years away.
The good news is that without the NMPWRC, we would not have made the progress we have today. The argument a few years ago was that we need to know every constituent in produced water. The NMPWRC took this task on and identified everything in produced water—a huge and unbelievably valuable undertaking. There does, however, continue to be opposition to this work that wants more studies and a deeper look into unknowns. These unknowns are potentially unidentified compounds that cannot be tested for, using today’s test methods. Although it may seem reasonable to request testing of unknowns, the concern over them exists in every water discharge today, but that does not stop the discharge.
We have general toxicity testing that can help determine if any potential unknowns pose a toxicity risk, and that’s part of how these unknowns or potential unknowns are addressed. A few years ago, nobody heard about polyfluoroalkyl substances (PFAS), but today we are finding it everywhere. The EPA is working to develop treatment standards for PFAS, but all these discharges of PFAS continue; wrong or right, we would be shutting municipal treatment plants across the country, forcing everybody to stop using water, because there would be nowhere for it to go.
So, we should continue to work to identify potential reuse scenarios and then develop appropriate risk-based standards for each of these scenarios and let the data and risk modeling speak for themselves like we do for every other discharge of water. Now, technology developers have a treatment goal to design to. No more “chicken and the egg.” I’m glad to say that the NMPWRC seems to have this task moving in the right direction and has all the right stakeholders in the room for an open, transparent dialogue. There is, however, another layer to this chicken and the egg problem.
Look at the end result. We have been spending most of our time identifying and characterizing raw, untreated produced water. This is beneficial, but now the focus is on what raw produced water looks like. Would you buy clothes if I showed you a pile of fabric, or do you want to see the finished product? Today, we use treated sewage water for landscape irrigation and groundwater replenishment and show everybody the finished product after treatment. With this, we received public approval, and these programs continue to grow. Now, what if we published the results of what raw sewage looks like and said, “we are going to turn this into discharge quality water and one day, you will be drinking it.” I can guarantee we never would have progressed with landscape irrigation or groundwater replenishment that becomes groundwater for drinking water, amongst other uses.
I’m not suggesting we ignore what the raw product looks like; again, this is a beneficial step in helping understand the required treatment, but the missing piece is what the product looks like. Here we are, back to the chicken and the egg. We need to develop use-specific standards, that allow appropriate risk calculations to be performed and provide the technology developers with a goal. Otherwise, we will continue to see the moving finish line we never reach. I’m glad to say that NMPWRC seems to be managing this minefield quite well.
I can’t stress the importance of this effort. Much of the produced water today is generated in drought-stricken areas, and the ability to create a new water source from produced water should be a priority. This is too large a concern to ignore or take lightly. Texas also recently formed a produced water research consortium that I expect will further these goals and add more resources behind the effort of the NMPWRC. I know they are already having discussions with each other. Imagine how our industry will change, if produced water becomes the solution to droughts in Texas and New Mexico. Talk about a game-changer. I will continue to update you on the progress of this topic.