Best Practice Recommendations for Storage of Manufactured Aggregate

CA was retained for the investigation into the alleged environmental damage caused by the handling and storage of manufactured aggregate in the Dominican Republic. All of the material testing reported by the different independent testing agencies confirmed that the raw materials were nonhazardous, non-toxic, and did not represent a danger or hazard to the environment. Visual inspection of the alleged affected areas at the ports of Manzanillo and Arroyo Barril revealed no evidence of distress to the adjacent waters including mangroves and bay shoreline, nor to the adjacent vegetation. CA concluded that manufactured aggregate being stored and/or used at the ports of Manzanillo and Arroyo Barril was non-hazardous. However, there were some deficiencies in the handling, storage, and/or installation of this material at both facilities that needed to be addressed to comply with industry standards for these activities. CA recommended that, in order to ensure the long-term benefit of the cargo storage and truck parking/staging area, the entire area be compacted, re-graded, surface sealed, and that a granular wear course be installed to prevent excessive surface wear and provide and act as a dust suppressant during traffic.

Sustainable Construction: Utilization of Coal Combustion By-Products

CA was retained by AES Puerto Rico to work on developing and evaluating alternatives for the utilization of coal combustion by-products from the production of electricity by AES in their plant in Guayama, Puerto Rico. Among the many alternatives developed, the use of the by-product for producing unbound granular fill and base material for highway construction and in flowable fill applications in construction were found to be promising. CA performed materials characterization as well as trial mixes and mock-up placements for this application. The evaluation and analysis of the strength development properties and chemical and mineralogical examination of samples at different ages and different exposure conditions was done in collaboration with Texas A&M University. Of great importance in this materials research project was the development of the necessary guidelines for ensuring the dimensional stability of the material while in service.