VAASPHALT.ORG 23 Ronnie Jacko ronnie@llmpubs.com 503.445.2234 Another major challenge comes once again in the LCA portion of the concrete and asphalt pavement comparison. Just as the industries have disagreed over the performance cycles and timelines in a life cycle cost analysis, the same holds for LCAs. Beyond the “cradle to gate” or even the construction stage of the LCA, the use stage and end of life stage will be the components determining the overall environmental impacts of a pavement structure. The use stage includes considerations such as maintenance operations, traffic impacts, performance cycles, rehabilitation and reconstruction. Fortunately, with asphalt pavements, the speed of construction and maintenance reduces impacts on traffic. Additionally, asphalt pavements can be maintained at a higher level of smoothness and condition, thereby reducing vehicle operating costs, and very few asphalt pavements are removed at the end-of-life stage. Unless significant design changes are needed, existing asphalt pavements become integrated into new roadways. To maintain functionality, the use stage for concrete pavements includes grinding, patching, and asphalt overlays. At the end of concrete pavement’s performance life, the slabs are either removed, structurally overlaid, or fractured and overlaid as part of new roadways. Agreeing on the LCA details will be a major hurdle to comparing the pavement types. Now That You Can Spell EPD, Do You Understand EPD? Simply put, EPDs are another metric to show a material’s environmental and economic advantages. Like putting together the first cost for a project, the first EPD for a mix or plant will take time. However, once the information is gathered, processed, and input into the Emerald Eco-Label program or other verified processes, the next iterations of EPDs will take less time. Companies that run multiple plants with various aggregates and fuel sources can analyze the EPDs to fine-tune their processes and become more economical. Also, companies with just a single plant or two will be able to compare their EPDs with other published EPDs in their state and nationally. It will be critical for the asphalt industry to develop and publish its EPDs with timeliness and efficiency. As of January 2023, over 400 EPDs were published nationally. While that seems like a large sample, it is just a start. Within Virginia, where nearly 100 asphalt plants operate, each plant could produce as many as a dozen different mix types, from surface to base mixes, since the A1, A2, and A3 inputs will vastly differ depending on the plant’s location. That alone would equate to 1,200 EPDs. Developing and publishing EPDs will be crucial in future conversations with legislators and regulators regarding the proper use of EPDs in the pavement type selection and project delivery process. Although agencies like the GeneralServices Agency have struck out on requiring EPDs for specific federal projects, other agencies like the US Department of Transportation, US Department of Defense and US Department of Interior will also require EPDs as part of the federal Buy Clean Initiatives. In addition, several states have implemented EPDs at the state level. It is imperative for everyone to become educated and join in the EPD conversation. CAN YOU SPELL EPD?
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