Index > 2 Development of a strategy, implementation and execution program to remediate radioactively contaminated sites >

2.10.1 Defining stewardship

The long term and life cycle management of radiological liabilities requires certain provisions and institutions. In recent years the term stewardship has been coined to describe the various activities associated with the long term management of sites with radiological liabilities [IAEA-2006c].

In general, ‘long term stewardship’ indicates the technical, societal and management measures needed to ensure the long term protection of humans and the environment at sites characterized by residual hazards after active remediation or assessment has been completed.
Different audiences have used the term ‘long term stewardship’ with different meanings. According to the Oxford English Dictionary, a steward is a person entrusted with the management of another’s property. In this sense, stewardship in the present context means taking care of sites or land with radioactivity in the ground. More specifically, it refers to those instances or phases of such sites, where, for instance, active remediation has been completed, but residual radioactivity is left, not allowing the free release of the site or land.

Accordingly, the United States Department of Energy (USDOE) defines stewardship as:

“The physical controls, institutions, information and other mechanisms needed to ensure protection of people and the environment at sites where DOE has completed or plans to complete ‘clean-up’ (e.g., landfill closures, remedial actions, removal actions, and facility stabilization). This concept of long term stewardship includes, inter alia, land-use controls, monitoring, maintenance and information management”.

Long term stewardship may also be defined as:

“The implemented institutions, controls, information, and mechanisms necessary to protect the public and the environment from legacy waste, radioactively contaminated sites and/or groundwater, deemed impractical, unsafe, or too costly to remediate to free release standards ”[EPA-1999].

Some other definitions can be read in a report by the National Research Council of the United States National Academies. This Council defined the roles of a long term steward of a site with long lived hazards as [USNRC-2003]:

  • A guardian, stopping activities that could be dangerous;
  • A watchman for problems as they arise, via monitoring that is effective in design and practice, activating responses and notifying responsible parties as needed;
  • A land manager, facilitating ecological processes and human use;
  • A repairer of engineered and ecological structures as failures occur and are discovered, as unexpected problems are found, and as (additional) re-remediation is needed;
  • An archivist of knowledge and data, to inform future generations;
  • An educator to affected communities, renewing memory of the site’s history, hazards and burdens;
  • A trustee, assuring the financial resources to accomplish all of the other functions.

The concept of long term stewardship is also known by several other names, depending on the organisation, for example:

  • Long term surveillance and maintenance;
  • Legacy management;
  • Long term monitoring and surveillance.

The scope of a stewardship programme is outlined explicitly by the IAEA [IAEA-2006a], [IAEA-2006c]:

“The type, extent and duration of the restrictions and controls for site release can range from monitoring and surveillance to restriction of access to the site. They should be proposed by the operator on the basis of a graded approach and in consideration of factors such as the type and level of residual contamination after completion of clean-up; relevant dose constraints and release criteria; and the human and financial resources necessary for the implementation of the restrictions and controls. The restrictions proposed by the operator should be enforceable by the regulatory body and the clean-up plan should specify which entity will ensure that the restrictions are maintained.”

Depending on the prevailing regulatory framework under which clean-up is to be accomplished, either the state, regional, tribal, or federal organisations will have to bear the responsibilities and/or authorities for long-term stewardship.

Nevertheless, it would always be the objective of life cycle management to minimize the need for stewardship within an overall optimizing management approach.

However, developing successful monitoring, institutional controls, engineering controls, maintenance activities and information management to last for hundreds, even thousands of years required for these radioactively contaminated sites and structures is a huge challenge.