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This was written by Nancy Spencer:

Et tu, VW?

In more than twenty years as an environmental enforcement lawyer and clean air advocate, I’ve encountered all sorts of violations, all sorts of violators, and just about every excuse and justification under the sun. I thought I’d seen it all. But this time, it’s personal. For the last three and a half years, I drove an Audi A3 TDI “clean diesel.” I loved that car. It was fun, it was zippy, it fit in any parking space. It combined fuel efficiency, power and low emissions in a way that seemed too good to be true … because it was.

It turns out that VW, which owns Audi, cleverly and deliberately designed a “defeat device” that reduced or turned off my emission controls in almost all driving conditions. Instead of driving a “clean diesel,” I have been driving around spewing dangerous nitrogen oxide pollution at levels up to 40 times those VW certified to the government and promised to its customers. And so has everyone else who drove an Audi A3 diesel or VW Jetta, Passat, Beetle and Golf diesel made since 2009.

Does it matter? It does. Diesel fuel is significantly dirtier than gasoline. It retains many of the contaminants left behind when gasoline and other lighter hydrocarbons are refined off the top of crude oil. Diesel exhaust is a toxic soup of dozens of hazardous pollutants. So why do we use it? Diesel engines, which cannot run on gasoline, are remarkably efficient and durable, and deliver power that is both reliable and responsive. Until recently, we paid the price for these advantages in smelly exhaust chock full of pollution. But in the last ten years, regulatory and technological developments made possible the Holy Grail of “clean diesel” that delivers the benefits of diesel power without its damning environmental and public health cost. Or so we thought.

The two main problems with car exhaust are soot and smog. Modern diesel-powered vehicles release dramatically less particulate, or soot, because EPA has slashed the levels of soot-forming sulfur in diesel fuel down to 15 parts per million, and automakers have installed diesel particulate filters that trap most of the remaining soot before it comes out the tailpipe. So far as we know today, these soot reduction benefits are real. Car exhaust forms lung-burning smog when the nitrogen oxides (NOx) it contains react with other pollution in the atmosphere. High sulfur levels in fuel prevented the use of emission controls to reduce NOx pollution. But the removal of most of the sulfur from diesel fuel enabled the use of modern emission controls that inject urea into the exhaust stream to reduce NOx pollution. This is where VW’s deception took place. It designed software that caused the emission controls to boost urea injection when the engine was being tested, and withhold urea from the exhaust stream the rest of the time. In short, the emission controls were almost never on at full strength, and these vehicles released uncontrolled NOx pollution to the air we all breathe, contributing to dangerous smog.

Now that the world knows that VW intentionally cheated emissions tests and concealed its deception, I feel personally defrauded, and also chagrined that I of all people fell for the con. My father suffers from chronic obstructive pulmonary disease, and is especially vulnerable to smog pollution. I worked on Clean Air Act mobile source issues for years. I wrote the petition asking EPA to list diesel exhaust as a hazardous air pollutant! I’d vaguely wondered if the dealer was recharging the urea supply in my A3 when I got the oil changed. But I’m not an engineer, and I wanted to believe the magic of this charming little car. I trusted a company that had the audacity to adopt “Truth in Engineering” as its slogan. If VW lied about its NOx pollution controls, we have to ask if this deception extends to other pollutants and other automakers? We don’t know. But it is obvious that our verification systems need a complete overhaul so we don’t get fooled like this again.

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Nancy Spencer is a mom and environmental attorney in San Mateo, California. She advises nonprofits on climate, clean air and corporate governance issues, and is shopping for a new car.


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