4. Example monitoring programmes
Source: gov.uk (2025-04-03)

Example programmes to guide you on what an appropriate programme could comprise for different impact sites.

These example programmes are to help you when designing a programme in conjunction with the monitoring objectives and the sources, receptors and pathways present.

Higher impact site

Assumed to have both aerial and liquid discharges to terrestrial, freshwater, and marine environments, impacting foods and environmental materials.

Example monitoring programme

Aerial pathway:
- dose rate monitoring terrestrial: 4 to 10 locations monthly to quarterly
- high volume air sampling: 1 to 4 locations monthly to quarterly
- total deposition: 1 to 4 locations monthly to quarterly
- water (tap, surface, groundwater): 2 to 5 locations quarterly to annually
- grass: 2 to 5 locations quarterly to annually
- soil: 2 to 5 locations annually
Food terrestrial pathway:
- milk and dairy products: 2 to 4 producers monthly to quarterly (regulator may do more for public reassurance purposes)
- fruit, vegetables, and cereals: 2 to 4 locations annually (regulator may do more for public reassurance purposes)
Aqueous pathway:
- dose rate monitoring inter-tidal or marine: 8 to 20 locations monthly to quarterly
- sediment: 8 to 20 locations quarterly to annually
- seaweed: 4 to 10 locations bi-annually to annually
- seawater: 1 to 4 locations annually
Food aqueous pathway:
- fish: 4 to 10 measurements per year (from 1 to 3 locations)
- crustaceans or molluscs­: 4 to 16 measurements per year (from 1 to 4 locations)
Sewage treatment works pathway:
- sewage or sludges: 4 to 7 locations quarterly to annually (to include raw sewage entering the works, treated effluent prior to discharge and final sludge prior to disposal)
Analytical requirements

For current discharges, analysis should be considered for:
- radionuclides which are limited in the permits
- significant components of a group limit (such as strontium-90 limited under any other beta or gamma emitting radionuclide group limit)
- radionuclides required as a result of international obligations
- radionuclides required for background
Proven surrogate radionuclides may be used (such as where the radionuclide fingerprint is relatively stable).

For historical discharges, and potential abnormal releases account needs to be taken of what radionuclides have been or could be expected to be released.

Lower impact site

Assumed to have both aerial and liquid discharges to terrestrial, freshwater, and marine environments, impacting foods and environmental materials.

Example monitoring programme

Aerial pathway:
- dose rate monitoring terrestrial: 2 to 4 locations monthly to quarterly
- total deposition: 1 location monthly to quarterly
- water (surface): 2 locations quarterly to annually
- grass: 2 locations quarterly to annually
- soil: 1 location annually – rotate between grass locations
Food terrestrial pathway:
- milk and dairy products: 1 to 2 producers quarterly from nearest farms if within 10km of site (regulator may do more for public reassurance purposes)
- fruit, vegetables, and cereals: 1 to 2 locations annually, if past data indicates detectable levels of activity. Otherwise grass data can be used as a surrogate (regulator may do more for public reassurance purposes)
Aqueous pathway:
- dose rate monitoring inter-tidal or marine: 2 to 8 locations monthly to quarterly
- sediment: 2 to 8 locations quarterly to annually
- seaweed: 1 to 4 locations quarterly to annually
- seawater: 1 location annually
Food aqueous pathway:
- fish: 2 to 4 measurements per year (from 1 to 2 locations)
- crustaceans or molluscs: 2 to 4 measurements per year (from 1 to 2 locations)
Analytical requirements

For current discharges, analysis should be considered for:
- radionuclides which are limited in the permits
- significant components of a group limit (such as strontium-90 limited under any other beta or gamma emitting radionuclide group limit)
- radionuclides required as a result of international obligations
Proven surrogate radionuclides may be used (such as where the radionuclide fingerprint is relatively stable).

For potential abnormal releases account needs to be taken of what radionuclides have been or could be expected to be released, but it is unlikely that historical impacts will need to be considered.

Decommissioning site

Transition from operations to decommissioning

Where operational discharges have ceased, but the discharge systems are still active, consideration needs to be given to what will be discharged by these routes. There could be temporary increases in certain radionuclides as clean-up is undertaken or the absence of others.

The monitoring programme at this time should evolve from the previous programme, but with particular attention paid to monitoring and sample types that act as good indicators (such as localised air monitoring, grass and seaweed).

Changes may be made to the analytical requirements. For example, removing radionuclides with short half-lives.

Decommissioning including possible period of care and maintenance

The possibility of new fugitive release pathways being created, needs to be considered, including dust, particulate, or remobilised activity from operations such as decontamination and demolition work or pipe removal.

The environmental monitoring programme may be revised at this point, but key receptors at points of maximum predicted deposition should be kept in place. Additional targeted monitoring may also be required to identify new fugitive releases during decommissioning activities, for example high volume air sampling or grass and total deposition sampling during building demolition. Or sampling of water courses near ground disturbances.

Triggers should be set to initiate investigative monitoring if fugitive emissions are found.

If there is a period of care and maintenance, process type monitoring should be considered for example monitoring for gases evolving from waste stores or detection of water ingress. As above, trigger levels should be set to initiate investigative monitoring. The environmental monitoring may still be required to meet the objectives of detecting abnormal, fugitive, and non-permitted releases and providing assurance. The magnitude of the programme required will be related to the level of clean-up undertaken, as this will affect the potential for releases.

Example monitoring programme

Aerial pathway:
- high volume air sampling: not for continuous use but should be considered in a targeted programme for demolition projects
- dose rate monitoring terrestrial: 2 to 4 locations quarterly
- total deposition: at location of maximum deposition, quarterly
- water (surface): 2 locations quarterly
- grass: 1 to 2 locations quarterly to annually
Food terrestrial pathway:
- fruit, vegetables and cereals: 1 location annually if past data indicates detectable levels of activity. Otherwise grass data can be used as a surrogate (regulator may do more for public reassurance purposes)
Aqueous pathway:
- dose rate monitoring inter-tidal or marine: 2 to 4 locations quarterly
- sediment: 2 to 4 locations annually
- seaweed: 1 to 2 locations quarterly to annually
- seawater: 1 location annually
- groundwater if aquifer present
Food aqueous pathway:
- crustaceans or molluscs: 2 to 4 measurements per year (from 1 to 2 locations)
Analytical requirements

Analysis should be considered for:
- radionuclides which are limited in the permits
- radionuclides that could be remobilised by clean-up and demolition