Can the Construction Sector Learn from the Nuclear Decommissioning

According to the International Atomic Energy Agency IAEA (2006), nuclear facilities may need to be decommissioned at the end of a research program, when the technology becomes obsolete, or due to policy change. Other reasons for withdrawing nuclear facility from service include economic factors and for safety and health concerns, leading to many retired nuclear facilities. The number of decommissioned nuclear facilities worldwide therefore qualifies it as a model for the study of end- of-life management in general and for the built environment in particular.

84

While the hazards associated with handling nuclear facilities may not be comparable with many other sectors, the experience acquired makes it a valuable asset worthy of study. This can be in the areas of health and safety, techniques, equipment, methods and costs. Moreover, nuclear plants belong to the category of infrastructure designed ab initio with a predetermined lifespan, which makes a withdrawal plan very crucial (Joint US/Russian Study Team, 1998). Decommissioning plans and updating the plans is part of the mandatory requirements for issuing nuclear operation licence (UNEP, 2012). Equally, buildings can be designed with predetermined lifespan, and incorporating decommissioning plans as part of the requirements for building permit may be desirable.

Accident in the nuclear sector makes safety issues much more essential (UNEP, 2012). These issues include construction quality, operations and maintenance, reliability of equipment, and emergency preparation (Holt, 2009). An assessment of human and environmental hazards associated with nuclear decommissioning and mitigation plans are requirements of the IAEA safety standards. Every task in the process of decommissioning should be evaluated in terms of the environmental and human hazards, a detailed management plan should be in place as early as possible. The safety and precaution plans should cover workers and the public, during and after the operations. Additionally, the management of the waste to emerge from the decommissioning activities should be planned beforehand (International Atomic Energy Agency IAEA, 1999). While the requirement for waste management plan is an existing regulation for construction works in the UK (Osmani, 2012), however, the detailed health and hazards precautionary and mitigation plans specific to building decommissioning will need to be developed.

The IAEA, gives three ways by which nuclear facilities can be deconstructed - immediate dismantling, deferred dismantling (safe enclosure), or entombment (International Atomic Energy Agency IAEA,

85

1999; UNEP, 2012). In the US, the immediate dismantling method is called “DECON”, while the deferred dismantling is referred to “SAFSTOR” (Joint US/Russian Study Team, 1998). Entombment is a method whereby the nuclear reactors are enclosed with a membrane usually concrete for long period until it is safe (Joint US/Russian Study Team, 1998; UNEP, 2012), an action not needed in the building sector. However, the DECON and SAFSTOR methods may be recommended for buildings decommissioning depending on the circumstances. Prompt dismantling of buildings may be justified if there is an emergency that threatens safety and health, like in the case of accident or risk of damage to neighbouring buildings. Nevertheless, the gradual processes of the SAFSTOR are likely to be more in line with the principles of sustainability.

The first stage of SAFSTOR involves withdrawal from service, suspension of all active services (electrical, mechanical, etc), and removal of all hazardous and useful materials (Joint US/Russian Study Team, 1998). In the nuclear sector, this stage may take up to five years, however, for buildings, the procedures may be adopted with all the advantages realised in shorter period. Stage 2 entails partial restrictions of access and usage of the facility including restriction of access to the hazardous zone. In the same vein, this stage can be emulated by the building sector, whereby partial access is permitted to salvage all useful items. Stage 3 is the final removal of the facility to allow unrestricted use of the land for the same or any other purpose. While the time taken to complete stage 1 to 3 for nuclear facilities may take 5 to 135 years depending on location and circumstances (Joint US/Russian Study Team, 1998), the benefits of the processes can be realised in the building sector within a relatively shorter period as indicated in table 1.

86

Table 1: LESSONS FROM "SAFSTOR" NUCLEAR DECOMMISSIONING PROCESS

SAFSTOR NUCLEAR DECOMMISSIONING

PROCESS

LESSONS FOR BUILDING DECOMMISSIONING

STAGE

I Officially, shutdown, fuel and fluids removed, and operating

system disconnected. Restricted access only for

safety purposes

Decision to retire building, disconnection from services, Restricted access for removal of all useful and moveable items STAGE

II Limited access, and use of the site. Only hazardous areas are restricted.

Unlimited but careful removal of all materials that may be useful without compromising the structural stability of the building

STAGE

III Final removal to allow unrestricted use of the nuclear facility

Final removal to allow unrestricted use of the building

The responsibility for the nuclear decommissioning was transferred to the utilities from the US Nuclear Regulatory Commission (NRC), however, there are several NRC rules regarding decommissioning. Other requirements are Occupational Safety and Health administration (OSHA), and National Environmental Policy Act (NEPA). While programs like OSHA and NEPA are generic in nature, the NRC rules are specific to the nuclear sector (Joint US/Russian Study Team, 1998). The equivalent of these policies specific to the construction sector in the UK is the expunged Site Waste Management Plan (SWMP) Regulation that was not specific to decommissioning. This implies the potentials for improvements in the building decommissioning sector.

In the nuclear sector, the cost associated with decommissioning is usually very significant (3-5%) and financial plans become crucial. Depositing money in a dedicated account before commencing operations sometimes finances nuclear facility decommissioning. Alternatively, certain part of

87

the electricity tariff is continuously saved into a dedicated account for the decommissioning operations. The other method is the surety fund, letter of credit or insurance policy for the nuclear facility (Joint US/Russian Study Team, 1998). The three methods of financing nuclear decommissioning can be adopted when retiring buildings that may require significant funding. Nevertheless, it is believed that retiring buildings if managed properly may be self-funding or even generate profit.

While the radioactive waste is managed at the global level, with a conventions ratified by 62 countries (UNEP, 2012); there is the OECD/NEA international collaboration program launched in 1985 - International Cooperative Program for the Exchange of Scientific and Technical Information Concerning Nuclear Installation Decommissioning Projects. The purpose of this program is to share knowledge and experience of nuclear decommissioning among member states. Some of the areas covered by the program include assessment methods, cutting techniques, remote operations, waste management, health, and safety (Joint US/Russian Study Team, 1998; Nuclear Energy Agency NEA, 2013). There may be International Cooperative Programs for the Exchange of Scientific and Technical Information Concerning buildings, however, not in the same scale and specific to decommissioning as in the nuclear sector. Furthermore, specialised equipment and technologies including remote operations, equipment for handling radioactive liquid or solid waste, among others have been developed for nuclear facilities decommissioning purposes (Joint US/Russian Study Team, 1998). One of the approaches to nuclear facility decommissioning is the installation of waste processing plants on site. Equally, in the construction sector there is the need for specialised bespoke equipment and technology that is different from the conventional tools, which will make dismantling of buildings more sustainable. The personnel, method, and organisation of activities in nuclear facility dismantling is usually determined by the assigned time

88

frame (Joint US/Russian Study Team, 1998). This can logically be applicable to the construction, and any other sector, as generally the faster a task is required to be completed the more personnel, or equipment will be needed. Nevertheless, the organisation of activities in the nuclear decommissioning can provide a good lesson for other sectors. The dismantling tasks are categorised into different groups such as hazards, or technical classification.

The International Atomic Energy Agency IAEA (2006), gives an outline of the nuclear decommissioning process as six major groups of processes. This includes withdrawal from active service, removal of radioactive substances, and decontamination and cleaning. Others are dismantling of structures, waste management, and unrestricted release of site. Each of these six processes of the nuclear decommissioning can have a matching corresponding process in the building decommissioning as indicated in Table 2.

Table 2: LESSONS FROM INTERNATIONAL ATOMIC ENERGY

AGENCY (IAEA) GENERAL NUCLEAR DECOMMISSIONING PROCESS.

IAEA NUCLEAR

DECOMMISSIONING PROCESS

LESSONS FOR BUILDING DECOMMISSIONING

STEP

I Withdrawal from active service Decision to retire building, and all usages come to stop including utilities supply

STEP

II Removal of Radioactive substances Removal of all hazardous substances STEP

III Decontamination and cleaning Salvage of materials, fittings and fixtures STEP

IV Dismantling of structures Dismantling of structures STEP

V Waste Management Waste Management

STEP

89

The construction industry can learn from the nuclear sector the tradition of designing nuclear plants with pre-determined lifespan as part of the requirements for building permits. This may include decommissioning plans and updating the plans as part of the mandatory requirements for issuing construction licence, similar to the nuclear sector.

The IAEA three methods of nuclear facilities deconstruction may not be directly applicable to other industries; however, the detailed process mapping as in the foregoing discussion can be emulated in the construction industry. Similarly, the methods for financing nuclear sector decommissioning may be applicable in the construction sectors, where the demolition costs become significant. Nevertheless, in building demolition projects where the decommissioning cost is insignificant, self-financed, or even profitable, such a plan may not be necessary. The health and safety precautions adopted in the nuclear sector may be transferable to construction more especially regarding hazardous materials. However, the type of material to be handled becomes very critical in deciding the most appropriate handling method.

Whilst in the foregoing sections different sectors were evaluated for lessons to be transferred to the construction, the next section is about inspirations from the Mother Nature on the best approach for managing materials at the end-of service.