ARPA Concrete Technical Committee Meeting

I recently attended a meeting of the ARPA Concrete Technical Committee. This committee is comprised of material engineers from member companies along with civil engineers from the Arizona Department of Transportation (ADOT). In addition to mining aggregates, many of the ARPA member companies also are suppliers of  concrete that is used on all types of construction projects. The technical committee was formed to design concrete mixtures that will be utilized on ADOT roadway and bridge construction throughout the state. The reason for this meeting was to satisfy a  request from ADOT to develop a  single mixture design that will be used on all refurbished and new bridge decks in the state. The difficulty with this task is Arizona has a diverse climate. Traditionally, concrete mixture designs for environments that experience a weather cycle that include a pattern of freeze/thaw - Flagstaff - have been vastly different than areas that do not have this type of weather pattern. Freezing and thawing is destructive to concrete. This is compounded by the use of corrosive road salt that is placed on street surfaces to eliminate icy street conditions. 

One way to mitigate the damage caused by freezing and thawing is through the use of additives in the concrete mixture. One such additive is Fly Ash, a bi-product of burning coal to generate electricity. Now that you have had a lesson in concrete technology, you are wondering: what does this have to do with public policy? There is an ongoing policy discussion regarding the use of Fly Ash. The EPA has suggested that Fly Ash is a hazardous material and should be treated as such. If Fly Ash is deemed to be a hazardous material it will have a profound effect on how it can be disposed. Currently, the bulk of the Fly Ash being generated is dumped into landfills around the country. However, as a hazard waste this would not be possible. Disposal would require the material to be disposed of in a facility specifically designed to handle hazardous waste. This would be extremely expensive and has caused an outcry by the Coal and Energy Industries and has led to some intense lobbying of Congress by both sides. 

The main topic of the ARPA meeting was trying to determine if Fly Ash is indeed deemed to be a hazardous material and it is incorporated in the mixture, would this satisfy the EPA requirements of proper disposal. The industry material engineer's argument is that the Fly Ash would in essence be encapsulated in the concrete and would not be of any danger. However, ADOT is concerned that if the EPA disagrees, then all concrete that contains Fly Ash would have to be removed and disposed of in a hazardous waste facility. After two and half hours of discussion the only decision reached was that the committee will meet again next month to continue the debate. Policy decisions can take a long time...