Design, construction, and performance of a roadway cut slope through a flooded abandoned coal mine

Mark A. Styler, Ph.D., P.E.,1 Gene Janero, P,E,2

Abstract:

The Mon/Fayette Expressway Project is the design and construction of a new section of a high-speed limited access toll road. A portion of the new alignment cut through a hillside and into an abandoned deep mine of the Pittsburgh Coal Seam. A set of piezometers and borehole ground water measurements indicated that the mine was flooded at the cut-location with approximately 7-ft of standing mine water over approximately 50 acres of abandoned mine-workings. This situation was identified early, the problem was defined, and it was resolved through numerous discussions between the owner and design team across disciplines. In this presentation we are covering the technical aspects of geotechnical engineering for mine pools and general take-away messages for addressing high risk items in engineering design.

Bios:

Mark Styler, Ph.D., P.E. is the Vice President and Chief Operating Officer of American Geotechnical and Environmental Engineering, Inc. Mark obtained his Ph.D. at the University of British Columbia investigating the influence of geological age on the seismic properties of sand specimens between reconstituted samples in the lab and in-situ field characterizations. He previously worked on characterizing properties of soft fully saturated mine tailings and partially-saturated heap leach piles. Mark has worked at A.G.E.S. fulltime since 2018 as a geotechnical engineer and project manager for various transportation projects for PTC and PennDOT. Mark is the geotechnical project manager for the project under discussion today: the Turnpike’s Mon Fayette Expressway Section 53A.

Gene Janero, P.E., is a Senior Engineering Project Manager, Geotechnical, For the PA Turnpike Commission. Gene has 30+ years in geotechnical design and geotechnical project management. Gene worked for 20 years at Gannett Fleming (now GFT), where he was responsible for peer reviews, directing and performing geotechnical designs & reporting, and mentoring junior-level geotechnical engineering staff. Currently at the Commission, Gene is responsible for working with our design consultant partners, other Commission units and state agencies, on all geotechnical aspects of projects, through planning, design and construction phases, as well as long term maintenance.