Design of Horizon Waste Area 1

Walday Abeda, Richard Sisson

In the proceedings of: GeoRegina 2014: 67th Canadian Geotechnical Conference

Session: Mining Geotechnics

ABSTRACT: Waste Area 1 (WA1) was the first primary external waste disposal area for overburden material excavated at Canadian Natural's Horizon mine. WA1 was located adjacent to the mine pit and key infrastructure for Horizon. Three weak soil units that significantly influenced the design and construction of WA1 are very soft muskeg deposits, Clearwater clay units that are weak due to glacially pre-shearing, and Marine clays in the Upper McMurray that are similar to the Clearwater in engineering characteristics. This paper describes a case history illustrating the selection of geotechnical design parameters and risk management strategy along with the subsequent geotechnical design. Performance data for WA1 are also presented. RÉSUMÉ 1 INTRODUCTION Canadian Natural Resources Limited (Canadian Natural) produces synthetic crude oil from the Horizon Oil Sands, 75 km north of Fort McMurray in northeastern Alberta. Horizon Oil Sands consists of a truck and shovel open pit mine operation and an oil sands plant for extracting and upgrading bitumen from the McMurray Oil Sands deposit. The layout of Horizon Mine is shown on Figure 1. When mining began in the South Pit, Waste Area 1 (WA1) was the first primary external waste disposal area for the initial overburden material excavated from the Ore Preparation Plant (OPP) site and the Southwest opening pit. As shown on Figure 1, WA1 is located on a waste pillar between the North and South Pit limits with an average toe offset of about 150 m from the final pit limits. The area between the pit limits and WA1 contains important infrastructure including: · A tailings pipe line corridor, a 72 kV power line right of way and an Ore Preparation Plant (OPP) on the south side of WA1. · A haul road and a 240 kV power line right of way on the north side. · A 240 kV substation and Horizon plant infrastructure on the east side of WA1 Challenges presented during design of the waste disposal area were the presence of pre-sheared clay shale, variable and sometimes soft glacial till deposits, and the need to place high moisture mine waste. Site specific field information was limited because the location of WA1 was identified during optimization late in the planning for the Horizon Figure 1 Horizon Site Plan

RÉSUMÉ: n of Horizon Waste Area 1 Walday Abeda, P.Eng.

Access this article:
Canadian Geotechnical Society members can access to this article, along with all other Canadian Geotechnical Conference proceedings, in the Member Area. Conference proceedings are also available in many libraries.

Cite this article:
Walday Abeda; Richard Sisson (2014) Design of Horizon Waste Area 1 in GEO2014. Ottawa, Ontario: Canadian Geotechnical Society.

@article{GeoRegina14Paper412,author = Walday Abeda; Richard Sisson ,title = Design of Horizon Waste Area 1,year = 2014}