Engineer of Record Services for Tailings Facilities
Authors: Paul W. Ridlen, PE; Thomas F. Kerr, PEng, PE; David Morgan, CEng
Issue: August 2021
Introduction
The Engineer of Record (EOR) concept originated in North America and has been used for private and public works construction since at least the early 20th century. It gained significant attention in the U.S. after the 1981 Hyatt Regency disaster in Kansas City, Missouri, which led to written guidance in the 1980s and 1990s by professional organizations and regulatory bodies to define typical duties and obligations of an EOR.
Applying the EOR concept to a tailings facility is more challenging than for a building, bridge, or water dam, largely because of the ongoing nature of construction. In addition, the complex behaviors associated with tailings and the potential for brittleness and/or liquefaction require special knowledge and training for proper design and monitoring of tailings facilities through their lifespan. Forensic investigations for recent tailings dam failures have identified the importance of the EOR role to reduce risk and prevent failures. These forensic investigations and efforts by the professional engineering and mining communities have led to a consensus in the industry that Owners are best served when continuity in the EOR is maintained through design, construction, and operational phases (and into closure when possible). The Global Industry Standard on Tailings Management (“Global Standard”) reinforces the importance of EOR continuity.
There remains significant uncertainty about what an EOR is and how to implement the concept on tailings projects. Knight Piésold has prepared this guide for implementation of the EOR concept for the projects and Owners we support. This paper addresses only the case of an external EOR, which is one of the two primary models recognized by the Global Standard.
Implementation of the EOR concept involves both an individual and a company, as reflected in the Global Standard. Knight Piésold clarifies these relationships by using the term “EOR Company” to refer to the Knight Piésold operating company that enters into a contract with an Owner to provide EOR services. The individual EOR is appointed by the EOR Company, subject to the Owner’s approval, to act on behalf of Knight Piésold to provide technical advice and leadership to the Owner.
Knight Piésold has been an industry leader in clarifying the role of the EOR for tailings dams, having influenced or informed the policies and guidelines of several mining companies, industry groups, and professional organizations. This white paper has been written to be consistent with the latest guidance from the International Council on Mining and Metals (ICMM), the Mining Association of Canada (MAC), the International Commission on Large Dams (ICOLD), and similar organizations.
Download the full white paper.