Project At-a-Glance
- Drill and Blast rock excavation methods to create shaft and CSO Storage Chamber
- Urban location
- Cavern is within limestone
Project Narrative
Brierley Associates served as Project Blasting Consultant under subcontract with the General Contractor, SAK, including blasting designs/drawings for submittal, and vibration impact and mitigation measures to the Project Designer, Jacobs Engineering. Construction included rock excavation by drill and blast methods and rock dowel installation during the construction of a 45-ft diameter access shaft extending 200-ft below the ground surface with 110-ft of Limestone bedrock. Blasting also included a 32-ft diameter storm water storage cavern that extends 1,800-ft west and 900-ft in the east directions with smaller access shafts and Adits at each end. The Maline Creek CSO project is part of St. Louis MSD Project Clear, which is a multi-year program undertaken as part of an agreement with the U.S. Environmental Protection Agency.
As blasting and rock excavation progressed, Brierley evaluated actual vibration and blast design data for regression analyses, revised blast designs as needed and provided comments on vibrations and air overpressures to maintain levels below the required contract limiting criteria.
