Any valid scientific study must, first and foremost, represent real world conditions within a controlled study environment to generate meaningful, accurate and reliable results.
We’ve touched on this topic before. But a quick look at a study by Andrew Whelton, Associate Professor of Civil Engineering and Environmental and Ecological Engineering, shows he failed to meet this basic standard. The study claims to assess the impacts on water quality from damaged plastic pipe after the wildfires from Northern California. Whether Whelton’s long-standing bias against plastic influenced his methodology and conclusions is unclear. What is clear is that his flawed findings collapse under scientific scrutiny. This was in fact confirmed to have occurred by the Paradise Town Manager who said they found contamination in both metal and plastic piping after the fire.
Good scientists are like detectives – they let the facts lead the way. They don’t guide an investigation toward a predetermined outcome. They don’t create fictional laboratory scenarios that would never represent reality to condition the answers they seek. They aren’t driven by the level of news coverage they may generate for their work, the promotion they may receive from special interests, or the needless public fear their flawed research may spark. Above all, a good scientist will seek knowledge and adhere to the process of learning, rather than blindly defending results, especially if they are flawed.
Here are some of the reasons why Whelton’s study conclusions, originally published in The Conversation and reprinted by the Associated Press, Fast Company and other outlets, cannot be supported:
Whelton never tested an actual intact segment of plastic pipe for his research on … plastic pipe: He cut tiny fragments from each pipe and used them as the source material for his research. This does not accurately reflect how an actual plastic pipe would respond to a real fire. Without relying on an engineering analysis on how a pipe behaves in the simulated conditions he selected, Whelton promotes the work as being representative of just that.
Whelton then heated the fragments to an unrealistic extreme temperature that would likely compromise the structural integrity of the pipe itself. But he couldn’t account for this since he was using tiny pipe fragments, so his research doesn’t replicate how a plastic pipe would actually respond under such unrealistic laboratory conditions. Instead he selects “mass loss” as the first point at which degradation is detected, but a pipe is certain to cease holding its shape, much less holding water under pressure, at far lower temperatures.
Whelton then took the remaining remnants and manipulated them to increase their studied surface area, which artificially skewed the leachate results.
“If the concern is about safe water delivery,” the Vinyl Institute wrote, “then the test should reflect meaningful conditions where water is still being delivered. … If similar logic were applied to ductile iron piping, the researchers would have taken a piece of ductile iron pipe and submerged it in an acid bath to simulate the effects of acidic soil. This would of course lead to the pipe dissolving and leaching heavy metals such as chromium. The same exaggerated approach to making broad claims would have led to a statement that “exposing ductile iron pipe to typical soil conditions can generate detectable heavy metals that remains in the pipe and ultimately leaches into the water.”
Other organizations have challenged Whelton’s research. The Plastics Pipe Institute (PPI) points out that “The study done by Dr. Whelton and his group fails to present any practical, meaningful evidence of the effect of fire or heat on safe water delivery. “
PPI’s David Fink also stated: “There is no evidence that the heating or burning of plastic pipe is responsible for the contamination of the water system[s in Northern California].” But rather, “[a]s water is used for firefighting or it runs out, it creates a negative pressure that allows contaminants to be drawn back in. Backflow is the technical term, and it can occur regardless of the piping material.”
The town manager of Paradise, California has explained that their examination showed that plastic pipes were not the cause of benzene contamination and even pointed out that the town is replacing damaged plastic pipe with new plastic pipe.
The PVC Pipe Association recently published a report pointing out that “the primary source of benzene in forest fires is from the combustion of wood. Burning homes and other structures are secondary sources. And that “[t]he most likely source of benzene in municipal water systems after a wildfire is not from burning or melting water mains but from outside contaminants entering the system via damaged service lines. . . As water in the system is used to fight the fire, suction draws in contaminants.” And finally that “Santa Rosa and Paradise have confirmed that PVC water transmission and distribution mains were unaffected by the forest fires that impacted their communities. This fact alone makes it impossible for PVC pipe to have been a source of benzene contamination in these localities.”
These critiques call into question the methods used by Whelton and the real-world applicability of his findings. But these facts haven’t stopped the iron pipe industry from promoting Whelton’s flawed study. The large iron pipe manufacturers and their activist “consultants” have seized on it to promote their own products despite the fact that the most likely cause of benzene contamination – backflow drawing contaminants from wood combustion into the system through damaged service lines – is just as likely to happen with their products.
The press is also to blame for reinforcing the use of crude methods by giving them far more credence than they deserve. The Associated Press reflexively published Whelton’s study, which originally appeared in a publication called The Conversation, without doing any homework of its own to assess or evaluate its scientific integrity. Fast Company and Yahoo News did too. These outlets failed their readers and have fueled public fear by giving this study attention it simply doesn’t deserve.
MORE: The Facts About PVC Pipe and Wildfires