I’m Rachel Leven, a reporter with the Center for Public Integrity. We’re a nonprofit, nonpartisan, investigative news outlet. We just published my story that focuses on “emission factors”—the U.S. EPA’s estimates that help tell us what is in our air and where it comes from. These factors, which have been used by the federal government since before the EPA existed, impact everything from the amount of toxics that reach a community to the amount of greenhouse gases that are emitted into the atmosphere. That has major implications for our health and climate. But, according to the EPA’s own ratings, the factors are largely unreliable and rarely updated.

Here's my article: https://www.publicintegrity.org/2018/01/29/21492/most-epas-pollution-estimates-are-unreliable-so-why-everyone-still-using-them

Thanks for stopping by our AMA! That's a wrap. You can find us on Twitter at @rachelpleven and @publici, if you have more questions.

Proof: https://twitter.com/rachelpleven/status/958700413930364928 https://www.publicintegrity.org/authors/rachel-leven

Comments: 50 • Responses: 4  • Date: 

mrym_jml13 karma

Hi Rachel! What seem to be some reasons the EPA hasn't acted on this issue meaningfully despite major concerns raised over the years?

rleven13 karma

Hi @mrym-jml! Great question. It's very complicated. One major reason that's been cited in the past is lack of resources. Developing emission factors are really time- and money- intensive -- especially if the EPA is doing its own testing to develop factors rather than using already existing data. Part of what the EPA is working on now is automating that process -- getting companies to submit their emissions data electronically, and developing a program that will automatically identify decent quality data and use that to propose factors, which would address lots of the problems with these numbers. But the EPA again said this would depend on having the resources to complete this complex task, and wouldn't give a timeline for when that automation process would be fully developed.

QuerierJ6 karma

How did you find out about the problem? And what's the best way for someone to determine if unreliable emission factors were used in permits for facilities near them?

rleven7 karma

A lot of my co-workers at the Center kept seeing scientific studies and other reports noting the EPA's emissions estimates were unreliable for one type of pollution or another, especially for methane emissions. They kept noticing this term "emission factors." My editor asked me to look into it, and I found that these factors actually informed a lot of what we know about our air quality across pollution sources and kinds of emissions. I found a lot of government watchdogs had been concerned about this for a long time, and we knew it was a story.

As to determining if emission factors are used in facilities near you -- its difficult. There isn't a central database showing how these factors are being used -- every permit they're in, for example. But you can always reach out to local academics, your local environment agency or other sources to ask for more information on a facility near you.

rleven3 karma

Alright -- that's a wrap! Sorry for the earlier technical difficulties, but thanks so much for patience and your questions. Have a wonderful rest of your day.

forava71 karma

what first got you started with researching and writing about emission factors?

rleven4 karma

Emission factors actually kept coming up naturally in the environment team's reporting here at the Center, especially when looking at methane emissions So my editor asked me to look into it. As we learned how many of these factors were flawed, how much of our environmental protections by all levels of gov't they impact and how long the EPA has known about it these issues, we knew it was an important story to investigate.