Seventh Contest Winner… Next Quiz Question!

After a hiatus for a few weeks, we have a winner for our seventh quiz question!  Mike Duerre of Walhalla, North Dakota, was selected at random from the ten correct responders to our last coal ash question.

But before we get to the correct response, here is the contest question for this week:  What percentage of coal ash is recycled in the United States each year?

If you think you know the answer, e-mail it along with your name and contact information to

Last week’s question was:  When a ton of coal fly ash is used to replace a ton of portland cement in the production of concrete, approximately how many tons of carbon dioxide emissions are avoided?

The correct answer:  Approximately one ton!  Manufacturing portland cement is an energy intensive process. Coal fly ash is produced when coal is burned to generate electricity, so we might as well use it to reduce greenhouse gas emissions from cement manufacturing.  Almost 11 million tons of greenhouse gas emissions were avoided this way in the United States in 2007 alone.

Congratulations, Mike!


 Using coal ash in concrete reduces greenhouse gas emissions that are linked to climate change.

Posted by: on: Jul 29, 2010 @ 08:13