By David Venhuizen
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| David Venhuizen |
You may have noticed that a continuing theme in the pieces I have written for [ITALIC]Onsite Water Treatment[ITALIC] has been what it will take to maintain and expand the “onsite industry,” and in particular to establish and maintain its credibility as a permanent solution for wastewater management challenges. A critical aspect of this is the manner in which approvals are gained—or denied—to employ a device or strategy, and, as far as I can see, we are in real trouble there.
Part of the problem is process; part of it is substance. Let’s look at process first.
To my knowledge, only a few regulatory systems are taking direct responsibility for evaluating methods proposed for use in their jurisdictions and are rendering their own judgments as to the inherent capabilities of each method and its suitability for use in the lightly supervised environment of on-lot/small-scale management systems. Far too many shirk that responsibility and instead base that judgment solely on the presence or absence of a third-party “certification” of system performance.
Before proceeding, let me make it clear the intent here is not to vilify any given certification process. Rather, I merely question if any such certification, by itself, is a “proper” basis for a regulatory system to give blanket approval, no further questions asked, to a given method, and—even more importantly—if simply lacking such a certification is a “proper” basis for denying the use of the method. That is, should such certifications be simply one “screening” tool available to the regulatory system, or should it completely substitute for an independent knowledge of the method and judgment of its merit?
A case in point is provided by considering the method known popularly as an aerobic treatment unit, or ATU, and contrasting that to the recirculating “sand” filter—or, more generically, a recirculating biofilter, since media other than sand or gravel are also being employed in that method. All ATUs are truncated versions of some variant of the activated sludge process. Because each system does not faithfully execute any standard model, it does indeed seem that you need to explicitly test each such “widget.” Further, even a standard model-activated sludge process is somewhat theoretically limited in the onsite environment, since there is no theory of operation for the process that does not presume steady-state operation. But flows into onsite systems are not steady-state. Rather, these systems experience episodic loading: peak flows morning and evening, or perhaps periodic peak laundry days. As it is operating off-theory in this environment, an explicit evaluation is needed for each widget.
While all this indicates that regulators do indeed need the results of some sort of testing protocol in order to rationally evaluate a method like the ATU, this does not mean that any testing protocol by itself ensures field performance—that gets into the substance issues discussed below—so the regulatory system should still be capable of independently evaluating the prospects for actual field performance. Neither does it mean that every method also needs that sort of explicit testing protocol in order to allow the regulatory system to judge its merit. Consider the case of the recirculating biofilter system.
In contrast to ATUs, this is a process that is amenable to analysis based upon principles that have been derived from more than 100 years of research and practice. A regulator can review this method in light of that information and have a great deal of confidence that a certain level of performance would be consistently and reliably attained without an explicit test of the widget at hand. The system design and operation is quite transparent and—given that capabilities of different media are shown to be equivalent to sand/gravel—the results are quite predictable and consistent, as long as the established principles are faithfully executed by the design.
And that is the rub for the regulatory system—there is technical review and judgment involved. The regulatory system must therefore embody the competence to first gain the knowledge and understanding of those principles and then to analyze and judge whether each design does indeed faithfully execute those principles. Rather than provide the resources to gain and apply that expertise, many regulatory systems prefer to shunt off the evaluation to that third-party testing process, then use the resulting certification as the entire basis for approval. Of course, it is easier for the regulatory system to tell the applicant to go get the process “certified” than it is to understand it, and we all understand the difficulty regulatory systems may have in retaining that expertise so it would be continuously available. But refusing to independently review and judge concepts like a recirculating biofilter creates all sorts of mayhem.
The certification process is a business, and the cost to do business with it is high. It is reasonable to expect that such costs would be imposed by regulatory fiat only if there were a legitimate public purpose to be served by doing so. As outlined above, if one has a proprietary process that can only be proved by an actual test of that particular widget, then imposing a requirement for such a test appears to be reasonable (although, as noted, it is questionable if such a test should be the entire basis for approval of that widget in any given circumstances). However, if one presents a process that can be evaluated on the basis of readily available public domain information, it seems highly unreasonable—if not outrightly irresponsible—to require each applicant to “reinvent the wheel” with a formulaic test at huge expense solely for the convenience of the regulatory system.
In any case, the widgets that generated and continue to be the major focus of the testing protocols are indeed proprietary products, and their principals pay the price of certification in anticipation of making that and much more back by selling the products. Other processes are nonproprietary. While they could be configured into widgets that are vended just like systems in which the technological concept is considered proprietary, these are “open” technologies that anyone may employ, like recirculating biofilters. Such systems are more often advanced by designers because they are believed to be the “best” response to a given situation than by vendors who are motivated to sell a product. In the case of a “one-off” design using such an “open” technology, there is no fiscal motivation to pay for the certification process. Again, for the regulatory system to deny the ability to use that system simply because it chooses not to understand it seems rather irresponsible, and not in the public interest.
In any case, since the base technology is “open” and available for use by anyone, any number of applicants might advance their own widget embodying the identical technology, so would be required to independently evaluate essentially the same process. That seems like a waste of resources that could better be applied to using these system concepts to solve society’s wastewater management problems.
Now to the substance of the certification processes. As noted, the certification process is a business. As such, its basic motivation is to serve its clients, not to accomplish a regulatory function, a public purpose. For example, the main testing protocol being required by regulatory systems was created by and for the ATU industry explicitly to provide a “certification” since performance could not be derived from basic principles, as reviewed above. While it has been improved over the years, this procedure remains essentially a “lab test” that follows a fixed protocol and lasts only six months. Both the protocol and the term were most likely compromises with the needs of the companies that drove the process of creating the testing protocol rather than based on any rational consideration of how, and how long, one “should” test a unit to fully confirm its capabilities and expose its weaknesses—in particular, the O&M protocol necessary to ensure continuously reliable performance.
Contrast that testing protocol with, for example, the testing of the denitrifying “sand” filter process that was conducted in the Washington Island project. This entailed a two-year monitoring period of several systems under field conditions, exposing the systems to all the vagaries of loading, weather, and the O&M practices that were applied—or failed to be applied. This not only confirmed what the concept was capable of in terms of treatment quality (which essentially was already known from many previous research efforts), but it also showed what problems might occur and how they can be addressed, blunted, or avoided. A discussion of this experience, including monthly summary data tables for the five year-round systems, is available in the “Texas Regulators Guide to the Standard High Performance Biofiltration/Drip Irrigation ‘Waste’ Water Reclamation System” at www.venhuizen-ww.com.
This is only one of several research efforts informing us of the design principles and operating requirements of this technology, so that it can be expected to perform consistently and reliably under field conditions, without significant hiccups in effluent quality. By contrast, the lab testing protocol tells us little about field performance, and in any case it explicitly allows excursions in effluent quality—it is colloquially known in the field as “puking solids”—due to stress loading. The protocol cannot reproduce the variations in conditions that would occur in the field, so the evaluation has to be considered at best an indication of typical performance. It is also rather questionable if the testing period is long enough to expose O&M liabilities, so it provides little basis for evaluating the system’s ability to consistently and reliably maintain performance over the service life of the system.
Of course, the cost to reproduce a study similar to the Washington Island project for each bastardized variant of activated sludge technology represented by each ATU—or for any other widget—would be prohibitive, and this has resulted in a conspiracy of silence about the limitations of the testing protocols and what performance, absent additional longer-term field trials, can actually be consistently and reliably expected in the field.
Part of this conspiracy is to be found in the regulatory systems that choose to point at the certification as the basis for gaining approval in their jurisdictions, without inputting any independent evaluation of either the inherent capabilities of the technology or of its robustness in the environment where it must operate.
In particular, most regulatory systems ignore the entire issue of what constitutes adequate management of these systems, a matter that space requirements prohibit us from exploring further here. (This matter was discussed in my column in the January/February 2006 issue of OWT.)
All this impacts upon the credibility of the methods that can gain regulatory approval and thus are proliferating. On the one hand, methods of possibly questionable real merit are uncritically accepted, raising questions about how serious the approval process really is. On the other hand, the regulatory system’s complete deferral to a third-party, private sector, testing protocol as the entry fee for gaining approval blunts the use of open technologies, which many experiences indicate are inherently superior responses in the onsite environment.
These circumstances call to question how serious the regulatory system is about creating and maintaining a high-quality management system. That in turn creates questions about whether onsite/small-scale systems can provide permanent wastewater management systems, or if indeed the long-held view that onsite systems are just temporary until the sewer gets there is justified. And that is bad news for all who depend on the viability and vitality of this field for their livelihoods.
David Venhuisen has pioneered the use of alternative management concepts.
OW - March/April 2007 |
