Did a Coal Ash Trade Group Try to Pull a Fast One?

by Bill Chameides | February 13th, 2009
posted by Erica Rowell (Editor)

Permalink | 3 comments

Some 125 million tons of coal ash is produced per year. In 2007 only about 40 percent of this waste was put to use, as in soils. But a recent graph by a trade group might suggest a different takeaway with regard to how much is recycled.

Nigerian poet Ben Okri wrote, “The magician and the politician have much in common: they both have to draw our attention away from what they are really doing.” I wonder if the American Coal Ash Association had similar tricks up its sleeve with a recent graph it produced.

I recently wrote a series of posts on coal ash waste in the United States. In one piece, I examined the fate of the stuff, specifically how much is produced, how much is recycled, and how much is just dumped somewhere. Some of our information came from the American Coal Ash Association (ACAA). (I bet most of you didn’t know that there was a coal ash trade group or even that one was needed. Same here, but given the amount of coal ash we produce each year, I now understand why there is one.)

In the graphic below, the ACAA presents the data on:

  • how much coal waste (or coal combustion product [CCP], as it’s known in the trade) is produced in the United States,
  • how much is put to use, and
  • (by extension) how much is dumped.

Take a quick glance at the graph and come on back here.

The blue line (labeled “production”) and the orange line (labeled “percent use”) lie almost on top of each other, right? I don’t know about you, but to me that visual left me with a first impression that virtually all of the coal waste produced was put to use. It was only after a closer look and further research that I finally figured out that in fact only about 40 percent has been used in recent years.

Why the Graphic Is Accurate but Misleading

One of the reasons that the graph is so easily misinterpreted is that the right-hand axis uses a scale that tops out at 50 percent. Coincidence? Maybe, but take a look at the graph below the original (at the bottom of the page).

The Green Grok team redid the graph, using the entire scale: 0 to 100 percent for the right-hand y-axis. Now the percent use runs right next to the amount used, down near the bottom of the graph and way below the production line. In other words, the United States has produced a lot of the waste, but only a fraction of it has been put to use.

Which graph gives a more accurate “picture” of how much coal waste is used? Why do you suppose the ACAA chose to use the one they did?

Got a graphic you find confusing or misleading? Give us a shout, and we’ll investigate. For those of you interested in such graphic sleuthing, check out our post “Understanding Oil” in which we blue line (in big red corrections) a graphic produced by a well-respected news organization.

ACAA’s Coal Ash Graph

This graphic from the American Coal Ash Association shows the historical trends in the amounts of coal waste produced and used from 1966 to 2007. Also shown is the percentage of coal waste that is used compared to the total amount produced. (Source: – note: we have changed the title on this graphic to make it eminently clear what the graph is about.)

The Green Grok’s Coal Ash Graph

This graphic is an approximate recreation of the American Coal Ash Association’s graph of coal ash waste versus use. The Green Grok’s graphic highlights the visual difference between using the full percent scale on the right hand axis versus a fifty percent scale as found in the ACAA’s original graphic. See for more details. (Source of original graphic:

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  1. Greg M. Schwartz
    Feb 16, 2009

    I wonder if you’ve come across any instances where companies or agencies try to pass off coal ash contamination as ok because they’ve pulled a controversial SPLP test to show heavy metals below protection levels. I have been investigating just such a situation here in San Antonio, see: and

    • Bill Chameides
      Feb 16, 2009

      Dr. Chameides replies – Greg: Your articles about what is going on in San Antonio look pretty scary – I know I would not be happy if I was downwind of all that stuff. I am going to look into the SPLP test and get back to you. But even if accurate, I would be concerned that there is other stuff in the ash (like radioactivity) that has not been tested for.

    • wendy
      Feb 25, 2009

      Dr Chameides replies – Greg, I’ve done a little more digging on the SPLP test. As you probably know it is an EPA-approved analytical test designed to evaluate the mobility of certain hazardous compounds to soil and groundwater. Often it is used to decide whether contaminated soil can be left in place and what sort of engineering controls might be needed to protect groundwater. Nothing wrong there. What this means though, is that SPLP, or any other leachate test for that matter, is simply assessing the risk of whether a waste is likely to leach into groundwater. It tells you nothing about the risks from other exposure pathways such as inhalation and ingestion of airborne dust as in this case. Other tests would be needed to assess these risks.

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