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Recently there was a coal ash spill in Kingston, Tennessee. The coal ash involved measured 5.4 million cubic yards.

This has raised some questions about the safety of coal ash and also caused some people to ask, “Where might I find coal ash without being aware of it?”

The answers may surprise you, as coal ash may be in your carpet or under your golf course.

When coal is burnt for fuel, one of the byproducts is coal ash. So it stands to reason that as long as we use coal as a source of fuel, we will have to think about ways in which the ash can be utilized properly.

There are three types of coal ash. These are:

• Fly ash
• Bottom ash
• Boiler slag

Fly ash accounts for approximately 74% of the ash generated.

Coal ash is not yet regulated by the Environmental Protection Agency (EPA), even though it contains mercury, arsenic and lead, which are all toxic substances. Instead each of the United States is responsible for conducting regulation of the ash it produces. However the EPA does approve the use of coal ash in construction.

In 1996 approximately 22% of the fly ash produced was used for construction.

Its construction applications are many:

• It’s used for making cement and concrete products
• It’s used in structural fills and embankments
• It’s used as mineral filler in asphalt pavement
• It’s used to stabilize waste materials
• It’s used to level out uneven terrain on sites including housing developments, malls and runways.

To be used in this way, coal ash must meet certain requirements.

For example, in Portland Cement Concrete, fly ash must meet the standards of ASTM C618. The ASTM is the American Society for Testing and Materials.

The ash used to produce Portland cement actually allows some cutbacks in using oil. It would have taken 55 gallons to produce one ton of cement.

Coal ash has also been found useful in the making of:

• Paints and plastics
• Kitchen countertops
• Soil for growing plants. It increases crop yields.
• Bowling balls
• Vinyl flow covering
• Shower stalls

Studies have been conducted to determine the safety of some but not all, of these applications.