Location: Danville, PA
Owner: Danville Municipal Authority
General Contractor: The Quandel Group, Inc.
Date Complete: August 2011
This project consisted of the in-house design and installation of 499 7-inch micropiles for additions and alterations to the Danville Wastewater Treatment Plant in Danville, PA. The upgrades will allow the Danville Wastewater Treatment Plant to serve additional customers, including meeting the increased demand resulting from the expansion of the Geisinger Medical Hospital. To allow the existing facility to continue to serve customers, all micropiling work was performed while the plant was fully operational.
In an effort to minimize waste, micropiles were drilled from stone benches at the bottom of footer elevation. This meant drilling often took place in deep excavations with minimal room for maneuvering. Micropile installation was performed in two stages, with a large portion of the micropiles being installed adjacent to existing foundations which could not be disturbed. Duplex drilling methods were utilized to control cuttings and DEP erosion and sediment control guidelines were strictly enforced.
Verification and proof load tests were performed prior to production micropile installation to verify the design. In total, over 17,500lf of micropiles were installed over two phases. The first phase of the project consisted of 450 micropiles installed at four of the main facilities. This work was completed in the Fall of 2010. Phase two consisted of approximately 50 micropiles installed at five other facilities and was completed in August 2011.