Stewardship Cessation
Encyclopedia
Stewardship Cessation is a concept useful in System Engineering. Certain systems remain hazardous for a considerable period after their useful life, and will usually be managed to ensure that the public and the environment is not exposed to the hazard. It is incumbent on the systems designer to consider the outcome should this stewardship be discontinued for any reason, and to design a system which is as robust as possible in the event of stewardship cessation.
The most obvious example is the nuclear
industry, and the radioactive waste
it generates which will be a hazard for many centuries. In the present era, most high level waste is in still in currently managed facilities, but various methods are being considered for disposal. Most of the proposed disposal methods are designed to put the waste in a place so isolated from the environment that (it is hoped) immediate stewardship cessation would be safe and appropriate. However, many people are more comfortable with systems where the waste is still accessible, so that if there is an unforeseen problem with the disposal method, the waste can still be accessed to rectify the problem. These systems will still require some level of stewardship, but the system designer must consider that this may not be available for the hundreds of years required.
Another example is when Geostationary Communication
s Satellites reach the end of their useful lives. Stewardship cessation will occur hopefully in a planned manner, where the operator will move the satellite
to a somewhat higher orbit to minimise the risk that the satellite will be a collision hazard to other satellites in the geostationary arc (graveyard burn). Unplanned stewardship cessation will occur if telecommand access to the satellite's systems is cut off due to a failure, for instance in the telecommand receivers.
Reasons for stewardship cessation include:
The most obvious example is the nuclear
Nuclear power
Nuclear power is the use of sustained nuclear fission to generate heat and electricity. Nuclear power plants provide about 6% of the world's energy and 13–14% of the world's electricity, with the U.S., France, and Japan together accounting for about 50% of nuclear generated electricity...
industry, and the radioactive waste
Radioactive waste
Radioactive wastes are wastes that contain radioactive material. Radioactive wastes are usually by-products of nuclear power generation and other applications of nuclear fission or nuclear technology, such as research and medicine...
it generates which will be a hazard for many centuries. In the present era, most high level waste is in still in currently managed facilities, but various methods are being considered for disposal. Most of the proposed disposal methods are designed to put the waste in a place so isolated from the environment that (it is hoped) immediate stewardship cessation would be safe and appropriate. However, many people are more comfortable with systems where the waste is still accessible, so that if there is an unforeseen problem with the disposal method, the waste can still be accessed to rectify the problem. These systems will still require some level of stewardship, but the system designer must consider that this may not be available for the hundreds of years required.
Another example is when Geostationary Communication
Telecommunication
Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...
s Satellites reach the end of their useful lives. Stewardship cessation will occur hopefully in a planned manner, where the operator will move the satellite
Satellite
In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....
to a somewhat higher orbit to minimise the risk that the satellite will be a collision hazard to other satellites in the geostationary arc (graveyard burn). Unplanned stewardship cessation will occur if telecommand access to the satellite's systems is cut off due to a failure, for instance in the telecommand receivers.
Reasons for stewardship cessation include:
- Illegal or inappropriate disposal by the last user
- Unreasonable budgetary constraints from government or other body
- Cultural change by stewards leading to negligenceNegligenceNegligence is a failure to exercise the care that a reasonably prudent person would exercise in like circumstances. The area of tort law known as negligence involves harm caused by carelessness, not intentional harm.According to Jay M...
- Climate changeClimate changeClimate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
putting the system beyond reach (under sea or ice) - Global war
- Other catastropheDisasterA disaster is a natural or man-made hazard that has come to fruition, resulting in an event of substantial extent causing significant physical damage or destruction, loss of life, or drastic change to the environment...
leading to very few humans (e.g. epidemicEpidemicIn epidemiology, an epidemic , occurs when new cases of a certain disease, in a given human population, and during a given period, substantially exceed what is expected based on recent experience...
) - Societal breakdown
- For remotely operated systems, loss of communicationCommunicationCommunication is the activity of conveying meaningful information. Communication requires a sender, a message, and an intended recipient, although the receiver need not be present or aware of the sender's intent to communicate at the time of communication; thus communication can occur across vast...
with the remote segment of the system.