Dr. Anil Misra, UMKC civil engineering professor, and his students, are documenting the test project through sample analysis and field testing. "They will determine how the roads are standing up to traffic and the elements, and after the data is analyzed, Dr. Misra will present a paper on the results before the-American Coal Ash Association's 2005 biannual symposium," Fred said. In the mid 1990s, Dr. Misra and his students worked with KCP&L in analyzing the use of fly ash in clay soil stabilization. "Through that project, my students got excellent onsite exposure," Dr. Misra said. "And then this opportunity surfaced in Jackson County."

Fly ash, known for its innate ability to fortify concrete, is now being tested to see if it can do the same for county roadbeds in southeast Jackson County. A pilot project now under way involves a Kansas City Power &Light, Jackson County Public Works (JCPW), University of Missouri-Kansas City (UMKC) and Lafarge Corporation (KCP&L's fly ash marketer) joint effort. The partnership is striving to prove fly ash is the answer to protecting roadbeds from the constant onslaught of storm water, severe weather and erosion. 

Conservation cooperation

    KCP&L's desire to use fly ash in more varied applications stems from a partnership with the EnvironmentalProtection Agency (EPA). The Coal Combustion Products Partnership. (C2P2) program seeks to establish more markets for byproducts of coal plants, such as fly ash, reducing greenhouse gas emissions and land disposal requirements. "The EPA now understands that products it once considered waste can be utilized, allowing our valuable natural resources to be conserved. KCP&L signed on last year as a partner with EPA in the C2P2 program and Jackson County followed. This project is a wonderful example of government and industry cooperation. Through this demonstration project, I hope other counties will realize using fly ash in roadways makes good economic sense," said Fred Gustin, coal combustion products analyst and overseer of KCP&L's fly ash marketing efforts.

    KCP&L donated fly ash to be used in two rural county roadbeds (a stretch of more than two miles) near Oak Grove, Mo., and if subsequent testing proves positive, the method could be used throughout Jackson County. According to Fred, fly ash is successfully used in this type of road construction, called "full-depth cold inplace recycling," in neighboring states. He's confident it will work here.

More than 700 tons per mile

    "Fly ash provides a more stable, stronger and denser road base. It's self-cementing. In fact, it has the same components cement does but in different proportions, and it is much finer than portland cement," Fred said. Fly ash is a byproduct of burning coal, and KCP&L recycles about 175,000tons of it a year. While much of it is used by construction contractors in concrete production and soil stabilization, new markets need to be developed for the remainder.

    The roadbed application not only utilizes more than 700 tons of fly ash per mile of road, but also would enhance the recycling efforts of JCPW by re-using asphalt and other paving materials that have been on the ground for years. In the Oak Grove test project, the existing asphalt road was ground up in small chunks along with rock and dirt, and then water and tons of fly ash were added to the blend. The mixture was then compacted and groomed to form a roadbed, on which conventional asphalt was then placed.

    If using fly ash passes the local roadbed test, J.D. Stokes, Jackson County's public works director, foresees his county using it on rural roads, universally. He especially likes the fact Jackson County's older roadways are being recycled, in place, an effort wholeheartedly supported by Jackson County Executive Katheryn Shields. "County-wide, we're working smarter, not just harder, to make enhanced public works decisions that also have very sound environmental results. The bottom line is that we want to improve our roads, and it's hoped that approaches like this will allow them to last longer," Shields said. Stokes added, "Using fly ash could potentially be another tool in our road rebuilding toolbox, which will lower the life-cycle maintenance cost per lane mile and be environmentally sensitive."

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