More than enough has been written about the technical aspects of 1,4-dioxane treatment. The treatment technologies and constraints are now well established nearly a decade into dealing with its presence in groundwater at chlorinated solvent release sites. What we continue to see debated is the cost-benefit of different approaches. It appears that the marketplace is less certain about the cost structures associated with these approaches. Here is the framework we recommend you follow when choosing.
Screen technologies based on constraints – the physical, chemical and logistical specifics at your project will place a limit on the technologies you can easily consider. The presence of high concentrations of bromide or other naturally occurring chemicals may make some technologies less feasible, the physical setting or location of a site may place constraints on O&M, or a host of other considerations may impact the technology selection.
Clearly define your cleanup goals – Whether or not you need to meet MCL, whether you need to conduct mass removal, or whether you are just trying to achieve containment are all considerations that will impact your choice (and the cost) of treatment.
Balance long and short term costs – Some technologies come with a higher up-front capital cost or will provide for faster removal, others will rely more heavily on longer term O&M but may be less capital intensive at the start. We find many of our clients are heavily focused on the financial impacts of the first 3-5 years of the investment driving a preference for lower up-front costs, while others may be more focused on life-cycle costs. Be clear on what those preferences are for your organization.
Run the cost-benefit model – Once you have the technology and logistical options identified, it is time to run the cost models out and compare benefits. New advances in digital controls (yes, the ‘internet of things’ has come to remediation) may mean that long-term O&M is cheaper than you think, pushing the life-cycle costs down. Labor costs or challenges with site accessibility may balance greater up-front capital costs in the long run, making higher capital technology options preferable. It is pretty easy to run these costs out against each other to easily see the comparisons and weigh the benefits.
Yes, there are lots of opinions out there about costs and you will need to choose wisely which sources you rely on. If you use cost estimates from technology vendors, we recommend running thorough sensitivity analysis on the cost models so you understand where those estimates may be vulnerable, and identify contingencies you might need to carry.
The benefit of the last few years’ experience with 1,4-dioxane is that the technologies available are well understood. We believe the costs are nearly as well understood also if you know where and how to evaluate them.