The decommissioning of a power plant is a meticulous process that extends beyond the simple shutdown of operations. It involves a series of critical steps to ensure safety, environmental compliance, and site readiness for future use. Keith Kotimko, the U.S. Decommissioning and Demolition Leader for WSP, emphasizes that decommissioning is a distinct activity from demolition, serving as the necessary precursor to the physical tearing down of a facility.
Kotimko, who has overseen the decommissioning of seven coal-fired power plants in the past 11 years, outlines several fundamental actions involved in the shutdown process. These include the cessation of generation, thorough cleaning of major systems, draining of oils and fuels, purging of gas systems, and the complete removal of all stored hazardous and non-hazardous waste. The process culminates in de-energizing the assets and separating them from transmission and distribution systems. Utilities often manage these preparatory activities internally as a “last outage event” before vacating the site.
The primary driver for decommissioning, particularly for coal plants, has been economic factors, according to Kotimko. The availability of cheaper alternative generation options has led to the retirement of several facilities. However, the decommissioning process itself is not driven by economic factors alone. It is heavily regulated and varies depending on the type of power station, with different protocols for fossil fuel-burning units, nuclear power plants, or renewable energy sites.
Successful decommissioning hinges on detailed preparation that goes beyond standard operating procedures. Kotimko highlights three critical topics that, if handled correctly, can reduce added contingency costs in contractor bids, prevent environmental releases, and minimize expensive change orders later. First, decommissioning is not a standard plant outage. It requires a much higher standard of removal and cleaning, defined by a detailed scope of work that lists all systems requiring cleaning, specifies the means to access equipment, defines the required level of cleanliness, and identifies specific waste streams and their exact disposition.
Second, plant shutdown alterations must aid demolition work. While the ideal goal is to achieve a “cold, dark, and dry” state, continuous operations may be necessary. Owners must proactively evaluate what utilities they are willing to provide for the contractor’s use, including power, water, and treatment/discharge systems. All requirements for utility use must be specified in the demolition contractor’s scope of work.
The major challenges for companies involved in the decommissioning of power plants center around the owner’s expertise in generating power, not in shutting down, decommissioning, abating, and demolishing an entire plant. Kotimko identifies four common categories of change orders that stem from poorly defined cleaning scope, inadequate asbestos surveys, insufficiently detailed site/owner requirements, and poorly defined below-grade removal work. These challenges can be mitigated through vigorous upfront diligence, investing the necessary time and money, and utilizing a combined team of the owner and a highly experienced owner’s engineer.
The decommissioning of power plants is a complex process that requires careful planning, detailed preparation, and a thorough understanding of the unique challenges involved. As the energy sector continues to evolve, the lessons learned from these decommissioning projects will shape the development of future power generation facilities and the strategies employed to manage their eventual retirement.