Decommissioning is when an obsolete or unneeded facility is dismantled and made safe. The word itself, decommissioning, comes from two words: “decommission” (to remove the means of operation) and “disposal” (to dispose of safely).
During this process, companies will often put a program to clean up environmental contamination that may have been caused during the facility’s construction or operation.
How does decommissioning work?
There are various forms of decommissioning. One method is to terminate or shut down a facility and remove all operating equipment and components, such as tanks and pipes.
Another way is by taking the necessary steps to prevent further use; even if equipment remains, it may be isolated from other parts of the process.
A third option involves entombing, or encasing, a facility not to be used without significant dismantling.
Decommissioning usually involves the removal of liquids and gases (for example, storage tanks and pipelines) and non-hazardous solid material (such as concrete slabs). It also includes backfilling of mines to reduce the chance of collapse.
Disposing of a decommissioned nuclear power plant is not as simple as dismantling it and shipping off pieces to be recycled. Once a nuclear plant has been shut down, there are three possible fates for its remains: dismantling, entombment, decontamination, and mothballing.
Below is the purpose of decommissioning:
- To dismantle the facility safely and in a way that protects workers, the community, and the environment.
- Decontaminate any radioactive elements created during the facility’s operations to be safe for future use or disposal.
- Safely store, contain, or package radioactive wastes until a permanent solution is reached (such as storage at an off-site location).
- Reclaim any parts of the site not directly involved with the removal process.
Decommissioning steps
Some of the steps include;
- Decontamination
Decontamination refers to the process of making an item or area safe for handling, use, storage, transport, disposal or restoration. After a reactor is shut down and cooled down enough to stop its nuclear reactions, it may be possible to begin decontamination.
This step might include cleaning up fuel spills if any occurred during the shutdown. Specialized equipment is generally needed for this process, and the contaminated areas are typically isolated from the public.
- Preparations for Dismantling
During this step, more operating systems are removed to facilitate access later on. Access roads are constructed or improved, additional buildings are razed or decontaminated if necessary, cables are labelled and tagged, and equipment is inspected for possible re-use.
- Dismantling
This final step involves removing the plant’s major components, including the reactor vessel itself, steam generators, pump motors and piping, turbines, generators, reactor shielding, fuel storage pools, spent fuel pools, containment building materials, and more.
Bottom line
The process is different for each type of facility when it comes to decommissioning. However, the purpose remains the same: to ensure that all activity related to a former plant does not endanger people or the environment. That is why it is advisable to work with IQIP since they have the right experience.
It should be noted that decommissioning does not always mean destruction; some facilities may be made safe enough for other uses after they are no longer considered a risk.
