3. Sampling and monitoring techniques
The main monitoring techniques and sample types to meet different monitoring objectives. Includes information on typical locations and frequency for these.
This section provides guidance on the main monitoring techniques and sample types to meet different monitoring objectives. There’s more in ‘Determine what to monitor or sample (including how), where and how often’ in the designing environmental monitoring programmes section.
The information can be used to select the monitoring and sampling types which meet your programme objectives. Permit holders are still required to demonstrate their selected monitoring techniques and sample types represent BAT for their operations and environmental setting.
Where check monitoring is included as an objective you need to ensure that suitable equivalent samples are included in both the regulator and operator programmes to enable the comparisons to be made.
Objectives
The objectives can be grouped into those that can be met by the same set of monitoring and those that require discrete other sets of monitoring.
Group 1:
- provide assurance (most measurements required for this objective)
- assess total representative person dose
- assess total impact on wildlife
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: assess background (very far field).
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical monitoring locations
Group 1: For assessing representative person dose, providing assurance and assessing the impact on wildlife 1 to 10 locations per year considering the area of maximum predicted dose, those determined from habit surveys and others targeting large population centre or sensitive wildlife habitats. Workforce reassurance can be gained from locations around the site perimeter. For assessing long-term trends, understanding the behaviour of radionuclides and check monitoring use the area of maximum predicted dose.
Group 2: 1 to 2 background locations per year or as part of a national programme for example a 20 to 50km survey grid.
Group 3: 4 to 12 locations per year around a site’s perimeter (less for a coastal location). These are often covered by operators’ emergency arrangements.
Typical monitoring frequencies
Group 1: Continuous and or monthly to quarterly spot measurements. For understanding the behaviour of radionuclides and check monitoring spot measurements could be quarterly to annually and annually for assessing long term trends.
Group 2: Assessing background once every 10 years.
Group 3: Use continuous instrument-based monitoring.
Programme ranges to meet all objectives
Overall: up to 22 continuous measurements or 4 to 20 spot measurements per year from 1 to 10 locations.
Lower impact site: 4 to 48 measurements per year from 1 to 4 locations.
Higher impact site: 16 to 120 measurements per year from 4 to 10 locations.
Data requirements
Reporting units microsievert per hour (μSv/h) or microgray per hour (μGy/h) as appropriate.
How to monitor: fluctuating dose rate and secure location
Select passive dose rate monitor (such as a thermoluminescent dosimeter (TLD), film badge). Ensuring the instrument meets the defined performance criteria.
Establish cosmic and intrinsic background and correct measurements for these, as appropriate, clearly stating what corrections have been made.
Locate monitor at height of 1 to 1.5m in a secure location and such that shielding from source of exposure is minimised (for example away from walls, trees, hedges, and roads).
Instruments to be deployed for sufficient time to meet defined dose rate measurement limit, but subject to a maximum period of 3 months to minimise loss of monitoring data if instrument is lost or fails.
Take measurements to ensure dose rate is representative over a scale of up to 5 to 10m. This may be checked with spot dose rate measurements.
How to monitor: non-fluctuating dose rate and non-secure location
Select instrument to take spot measurement.
Instrument type chosen should have an appropriate type test that demonstrates it can meet defined performance criteria to include:
- inherent background dose rate <0.015μGy/h Ra-226 γ (or equivalent)
- cosmic ray response <0.07μG/h Ra-226 γ (or equivalent)
- Air kerma based response ± 30 % of the response to Cs-137 γ radiation over the energy range 80 kiloelectron-volt (keV) to 1.25 megaelectron-volt (MeV)
- adequate polar response
- precision
These criteria were originally defined in Technical Guidance Note (Monitoring) M5: Routine measurement of gamma air kerma rate in the environment. HMSO, 1995 and further information is given in the replacement Environment Agency guidance: The Measurement of Environmental Gamma Air Kerma Rates.
Individual instrument to be tested before use to ensure it conforms to type. More information available in the Measurement Good Practice Guide on The Examination, Testing and Calibration of Portable Radiation Protection Instruments.
Establish cosmic and intrinsic background and correct measurements for these, as appropriate, clearly stating what corrections have been made.
Ensure instrument is calibrated regularly (for example annually) and is functioning before and after monitoring survey period (or weekly).
Take measurement at height of 1m and locate such that shielding from source of exposure is minimised (for example away from walls, trees, hedges and roads).
Take reading over sufficient time to achieve sufficient statistical confidence at the defined minimum dose rate measurement limit.
Take measurements to ensure dose rate is representative over a scale of up to 5 to 10m. Normally, a single dose rate measurement will be representative at this scale, although dose rate can be measured at 2 to 3 locations at distances of 10m apart over the same ground type and an average result reported).
Note that where geology is changing rapidly it may be difficult to choose a reference background dose rate for comparison.
Objectives
The objectives can be grouped into those that can be met by the same set of monitoring and those that require discrete other sets of monitoring.
Group 1:
- provide assurance (most measurements required for this objective)
- assess total representative person dose
- assess total impact on wildlife
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: assess background (very far field).
Typical monitoring locations
Group 1: For assessing representative person dose and assessing the impact on wildlife 1 to 10 locations considering the area of maximum predicted dose and others determined from habit surveys or modelling and sensitive wildlife habitats. For providing assurance 1 to 20 locations also targeting non-critical habits further afield. For assessing long term trends, understanding the behaviour of radionuclides and check monitoring 1 to 3 locations considering the area of maximum predicted dose and locations in both directions from site.
Group 2: 1 to 10 remote locations (better achieved by analysing natural contributions at the site)
Typical monitoring frequencies
Group 1: Spot measurement monthly to quarterly – continuous measurement would be good, but prevented by practicalities. For understanding the behaviour of radionuclides and check monitoring spot measurements could be quarterly to annually and annually for assessing long term trends.
Group 2: Once every 5 to 10 years.
Programme ranges to meet all objectives
Overall: 4 to 242 spot measurements per year from 1 to 20 locations.
Lower impact site: 4 to 96 measurements per year from 1 to 8 locations.
Higher impact site: 32 to 242 measurements per year from 8 to 20 locations.
Data requirements
Reporting units μSv/h or μGy/h as appropriate.
How to monitor
Identify and note sediment type (for example sand, mud or grit), predominant weather conditions and location (for example high or low water mark).
Select instrument, capable of performing the measurement, to take spot measurement.
Instrument type chosen should have an appropriate type test that demonstrates it can meet defined performance criteria to include:
- inherent background dose rate <0.015μGy/h Ra-226 γ (or equivalent)
- cosmic ray response <0.07μG/h Ra-226 γ (or equivalent)
- Air kerma based response ± 30 % of the response to Cs-137 γ radiation over the energy range 80 kiloelectron-volt (keV) to 1.25 megaelectron-volt (MeV)
- adequate polar response
- precision
These criteria were originally defined in Technical Guidance Note (Monitoring) M5: Routine measurement of gamma air kerma rate in the environment. HMSO, 1995 and further information is given in the replacement Environment Agency guidance: The Measurement of Environmental Gamma Air Kerma Rates.
Individual instrument to be tested before use to ensure it conforms to type. More information available in the Measurement Good Practice Guide on examination, testing and calibration of portable radiation protection instruments.
Ensure instrument is calibrated regularly (for example annually) and is functioning before and after monitoring survey period (or weekly).
Establish cosmic and intrinsic background and correct measurements for these, as appropriate, clearly stating what corrections have been made.
Take measurement at a height of 1m.
Operator should stand at least 10m away from the detector to prevent effects of shielding.
Take reading over sufficient time to achieve sufficient statistical confidence at the defined minimum dose rate measurement limit.
Take measurements to ensure dose rate is representative over a scale of up to 5 to 10m. Normally, a single dose rate measurement will be representative at this scale, although dose rate can be measured at 2 to 3 locations at distances of 10m apart over the same ground type and an average result reported).
It can be useful to have calculated dose rate or count rate action levels in advance of monitoring so, if they are exceeded, any follow up actions can be undertaken straight away, for example collecting sediment samples.
Note that where geology is changing rapidly it may be difficult to choose a reference background dose rate for comparison.
How to monitor (exception)
For assessing total representative person dose the instrument chosen may be different and performance checks should include efficiency, sensitivity, precision, and energy response that matches the quantity of interest.
Measurement height should be appropriate to the habit being assessed (such as 15cm for seated anglers).
Take appropriate number of readings across the surface, to be representative of the item being monitored, with shield on (γ only) and without shield (β and γ).
Take reading over sufficient time to achieve defined dose rate measurement limit (using integrating function of instrument).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of monitoring.
Group 1
- provide assurance (most measurements required for this objective)
- check or complementary monitoring
- detect abnormal, fugitive, and non-permitted releases (indicator)
- understand or monitor behaviour of radionuclides in the environment
Typical monitoring locations
Group 1: For providing assurance 1 to 20 km of beach or inter-tidal areas (maybe broken into stretches), targeting occupied areas based on habit surveys and predicted concentrations. For check monitoring 1 to 2 locations. To detect abnormal, fugitive, and non-permitted releases 1 to 6km of the surveys should be close to the pipeline or modelled area of impact in both directions from the site. 1km of beach at areas of maximum contamination in both directions of the site would allow for an understanding of the behaviour of radionuclides in the environment.
Typical monitoring frequencies
Group 1: Monthly to quarterly, to detect abnormal, fugitive, and non-permitted releases, quarterly to annually for providing assurance and annually for the other objectives.
Programme ranges to meet all objectives
Overall: 4 to 80km of beach surveyed per year.
Lower impact site: 4 to 24km surveyed per year.
Higher impact site: 24 to 80km surveyed per year.
Data requirements
Reported in counts per second (cps) and µSv/h from the active items or object (if appropriate conversion factors available).
How to monitor (by foot or vehicle)
Identify and note the weather conditions and point in the tidal cycle, allowing for tide times to ensure access.
Select instrument to take measurements (for example a probe with Geiger-Muller detector when by foot or NaI(Tl) detectors in vehicles) that meets defined performance criteria, (to enable active items as defined to be detected) to include:
- detection efficiency and sensitivity capability
- precision
- detector should be chosen to maximise the ability to detect the potential contaminant taking account of the local background
- response time
Ensure instrument is calibrated regularly (for example annually).
Ensure instrument is functioning before and after monitoring survey period (or weekly).
Monitor strandline (order of importance is the most recent tideline, then the extreme high-water mark and wind-blown debris above the extreme high-water mark) by walking with instrument. Crevices can be investigated as necessary.
By foot: Probe should be kept just above the ground surface and moved in side to side sweeps at a defined rate allowing for instrument response time (for example < 0.5m/s). Looking to detect an increase in counts.
By vehicle: Rate of vehicle travel to be defined to allow for time for the instrument response and defined detection criteria to be met. Travel the area using sweeps, at intervals to meet defined detection criteria.
Procedures should be defined for what action to take if an active item is found. These will need to address health and safety requirements, responsibility for custody and detailed analytical requirements.
If increased count rate is associated with a wider area of contamination may need to move into a characterisation phase to determine its extent.
Record general count rate range for the defined transect that has been surveyed.
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of monitoring.
Group 1
- assess total representative person dose
- provide assurance
Typical monitoring
Group 1: 1 to 4 items of fishing gear – ropes, nets, or lobster pots as appropriate.
Typical monitoring frequencies
Group 1: Quarterly to annually – after fishing trip.
Programme ranges to meet all objectives
Overall: 1 to 16 measurements per year.
Lower impact site: 1 to 4 measurements per year.
Higher impact site: 4 to 16 measurements per year.
Data requirements
Reported as µGy/h.
How to monitor
Select instrument to take measurements that meets defined performance criteria, (to enable active items as defined to be detected) to include:
- detection efficiency and sensitivity capability
- precision
- detector should be chosen to maximise the ability to detect the potential contaminant taking account of the local background
- response time
Ensure instrument is calibrated regularly (for example annually).
Ensure instrument is functioning before and after monitoring survey period (or weekly).
Take measurement at just above the material being monitored, ensuring that window membrane is not punctured. For ropes and nets, monitor in the manner used by fishermen.
Take appropriate number of readings across the surface, to be representative of the item being monitored, with shield on (γ only) and without shield (β and γ).
Take reading over sufficient time to achieve defined dose rate measurement limit (using integrating function of instrument).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- provide assurance
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2:
- comply with international obligations
- assess background (very far field)
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: 1 to 4 population centres with highest predicted air concentration – reflect the wind-rose. For check monitoring, assessing long term trends and understanding the behaviour of radionuclides use the location with maximum air concentrations.
Group 2: 1 to 2 remote locations or as part of a national programme (1 to 10 locations). Could be done on a campaign basis.
Group 3: 4 to 12 locations around site perimeter (less for coastal location).
Typical sampling frequencies
Group 1: Continuous – quarterly campaigns, monthly filter changes, monthly to quarterly analysis batches. For understanding the behaviour of radionuclides use monthly analysis batches, for assessing long term trends monthly to annual analysis batches and check monitoring annual to 3 yearly batches.
Group 2: Continuous – monthly filter changes, monthly to annual bulks for analysis. Dependent on conditions for change frequency.
Group 3: Continuous – monthly filter changes monthly bulks for analysis of limited number of indicator radionuclides. Dependent on conditions for change frequency.
Programme ranges to meet all objectives
Overall: 4 to 48 measurements per year from 1 to 4 locations, for the main programme. Where relevant, 48 to 144 measurements for a limited number of radionuclides from 4 to 12 perimeter locations to detect abnormal, fugitive, and non-permitted releases. 1 to 120 measurements from 1 to 10 locations as part of a national programme for background and international obligations.
Lower impact site: 4 to 12 measurements per year from 1 location.
Higher impact site: 4 to 48 measurements per year from 1 to 4 locations and where relevant, 48 to 144 measurements for a limited number of radionuclides from 4 to 12 perimeter locations to detect abnormal, fugitive, and non-permitted releases.
Data requirements
Reporting units Becquerel per metre cubed (Bq/m3) (also Becquerel per kilogram (Bq/kg) for detecting abnormal, fugitive, or non-permitted releases)).
How to sample
Locate sampler at a secure site with a power supply and ensure the noise of the sampler is minimised. Samplers should be placed away from major obstructions such as trees or buildings. The air inlet should be representative of breathing height, at least 1.5m (but less than 4m) from the immediate ground level.
Should aim to collect data for at least 95% of the sampling period. Collect total particulate (not specific size range). This is a conservative approach for the objectives. Filters should trap >95% of particle size >0.3 micrometre (μm) aerodynamic diameter. Sample for a period to ensure that defined detection limits can be achieved and avoid filter blinding (2 weeks is typical). Mass of particulate collected to be measured (for example filters weighed before and after collection).
Filter material should be selected to help ensure the most suitable analytical method is used to achieve detection limits. Polycarbonate filter papers can be fully ashed and digested or quartz fibre filters can be leached to enable a solution to be analysed. This is likely to achieve a better detection limit than compressing filters and counting directly by gamma-spectrometry.
Sampling air flow to be measured with defined uncertainty (best practice instrument maintain flow rate automatically) – calibration will be required at installation, after motor or brush changes, when checks show deviation from defined uncertainty and on a regular basis (6 to 12 months).
Ensure filters can be identified (for example uniquely label filters) and avoid cross contamination (such as sealed in polythene bags, take blank filters to field).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- provide assurance (most measurements required for this objective)
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: 1 to 4 Targeting large population centres and including location of maximum concentration and, or 1 to 4 around site perimeter. For assessing long term trends and understanding the behaviour of radionuclides use the location with maximum concentration.
Group 2: 4 to 12 locations around site perimeter (less for coastal location).
Typical sampling frequencies
Group 1: Continuous sampling – monthly to annual analysis (could have more frequent sample change) for providing assurance, quarterly to annual analysis for others.
Group 2: Continuous sampling – monthly analysis
Programme ranges to meet all objectives
Overall: 2 to 96 samples per year from 2 to 8 locations for the main programme, and where relevant, 48 to 144 measurements from 4 to 12 perimeter locations to detect abnormal, fugitive, and non-permitted releases.
Lower impact site: 1 to 48 samples per year from 1 to 4 locations
Higher impact site: 2 to 96 samples per year from 2 to 8 locations and, where relevant, 48 to 144 measurements from 4 to 12 perimeter locations to detect abnormal, fugitive, and non-permitted releases.
Data requirements
Reported as Becquerel per shade (Bq/shade)
How to sample and prepare
Collect total particulate on suitable shade material. Sample for a period to ensure that defined detection limits can be achieved, but short enough to allow for detection of abnormal events.
Ensure shades can be identified (for example uniquely label shades) and avoid cross contamination (such as sealed in polythene bags, take blank shades to field).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- provide assurance (most measurements required for this objective)
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2:
- comply with international obligations
- assess background (very far field)
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: 1 to 4 Population centres with highest predicted deposition – reflect wind-rose (could be on site or at perimeter). For check monitoring and assessing long term trends and understanding the behaviour of radionuclides use the location at the point of maximum deposition.
Group 2: 1 to 2 remote locations or as part of a national programme (1 to 10 locations).
Group 3: 4 to 12 locations around site perimeter (less for coastal location).
Typical sampling frequencies
Group 1: For providing assurance continuous collection, monthly to quarterly bulks for analysis. Annual analysis on some radionuclides. For other objectives in this group use quarterly to annual bulks for analysis.
Group 2: Continuous collection. Monthly to annual bulks to comply with international regulations or quarterly to annual for assessing background.
Group 3: Continuous collection monthly bulks for analysis for a limited number of indicator radionuclides.
Programme ranges to meet all objectives
Overall: 4 to 48 samples per year from 1 to 4 locations for the main programme. Where relevant, 48 to 144 measurements for a limited number of radionuclides from 4 to 12 perimeter locations to detect abnormal, fugitive, and non-permitted releases. 1 to 120 measurements from 1 to 10 locations as part of a national programme for background and international obligations.
Lower impact site: 4 to 12 samples per year from 1 location.
Higher impact site: 4 to 48 samples per year from 1 to 4 locations and where relevant, 48 to 144 measurements for a limited number of radionuclides from 4 to 12 perimeter locations to detect abnormal, fugitive, and non-permitted releases.
Data requirements
Reported as Becquerel per litre (Bq/L), Becquerel per metre squared (Bq/m2) and Bq/m3.
How to sample and prepare
Collect in a deposition collector (for example a rain gauge). Record the area of the collection funnel and the time over which the sample is collected.
Ensure the sample collection period will not cause the sample container to over-flow, but that sufficient sample is collected to ensure the detection limit can be achieved. A typical collection period is 2 to 4 weeks.
Minimise adsorption of radionuclides to container (for example pre-soak containers and use carrier solutions) and minimise growth of algae (for example use brown collection bottle).
Store samples at the laboratory to prevent degradation and loss of volatiles, if appropriate (for example chill at about 4ºC).
Filter samples through a 0.45µm membrane and analyse filtrate and residue if the monitoring objective requires information on the partitioning between dissolved and particulate phases (for example particulate deposition).
Ensure a representative sub-sample is taken for analysis (for example shake liquid samples).
Bulk or concentrate samples (for example through ion exchange or evaporation) to achieve detection limits, if required.
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- provide assurance
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: assess total impact on wildlife.
Group 3:
- assess background (very far field)
- comply with international obligations
Group 4: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: For assessing representative person dose purposes 1 to 4 sources of drinking water for major populations (such as taps, reservoirs, rivers, groundwater) plus local water supplies (well, runoff, rainwater, or boreholes), based on habit surveys. Also, sources for irrigation or cattle drinking water. The number of locations could increase to 1 to 10 to provide assurance. For the other objectives in this group 1 of each water type based on habit surveys.
Group 2: Water courses with sensitive wildlife or ecosystem.
Group 3: 1 to 10 remote locations, upstream of site reflecting geology and type of water course, or as part of a national programme (20 to 60 remote locations).
Group 4: 1 to 10 locations downstream of site based on site hydrology. Due to dilution not a good indicator, except for ground water boreholes.
Typical sampling frequencies
Group 1: Quarterly to annually depending on the source. Composite bulk for higher doses. Annually for providing assurance, assessing long term trends and understanding the behaviour of radionuclides in the environment (may need to be more frequently for rivers). For check monitoring annually to 3 yearly.
Group 2: Quarterly to annually. Depending on source. Composite bulk for higher doses.
Group 3: Quarterly for a national programme or annually for assessing background (establish levels and keep check on less frequently).
Group 4: Monthly to quarterly, depending on flow rate analyse for limited number of radionuclides.
Programme ranges to meet all objectives
Overall: 2 to 20 samples per year from 1 to 10 locations for the main programme. Where relevant 4 to 120 samples analysed for a limited number of radionuclides from 1 to 10 locations to detect abnormal, fugitive, and non-permitted releases. 80 to 240 samples from 20 to 60 locations as part of a national programme for background and international obligations.
Lower impact site: 2 to 8 samples per year from 2 locations.
Higher impact site: 2 to 20 samples per year from 2 to 10 locations and where relevant 4 to 120 samples analysed for a limited number of radionuclides from 1 to 10 locations to detect abnormal, fugitive, and non-permitted releases.
Data requirements
Reported as Bq/L and Bq/m3.
How to sample and prepare
Surface freshwater (such as rivers, streams, lakes): Determine appropriate sample container dependent upon radionuclides to be sampled. Rinse collection apparatus and container with sample. Collect representative sample.
Filter samples through a 0.45µm membrane and analyse filtrate and residue if the monitoring objective requires information on the partitioning between dissolved and particulate phases. Ensure representative sub-sample is taken for analysis (for example shake water sample). Preserve with nitric acid for long storage (analysis dependant).
Drinking water (tap water): Determine appropriate sample container dependent upon radionuclides to be sampled. Decide upon whether you want mains tap water or the water from within the household pipework. Record site location of sample. Follow radon specific protocol if measuring for radon (for example US EPA guidance ‘Radon in water sampling program’). Rinse collection apparatus and container with sample.
Take representative sample bearing in mind the need to allow tap to run for adequate time interval depending upon sample type requirement (household or mains water). Collect water sample directly into the container.
Do not filter sample.
Drinking water (direct from groundwater via borehole or spring): Detailed guidance on collection of groundwater samples is available such as Environment Agency guidance on the ‘Monitoring of landfill leachate, groundwater and surface water’ and ISO 5667-11: ‘Water quality sampling – part 11: guidance on sampling of groundwater’. Determine appropriate sample container dependent upon radionuclides to be sampled. If used, confirm borehole is suitable for sampling and representative of the water consumed. Identify geochemical strata (water origin). Record site location of sample. Follow radon specific protocol if measuring for radon (for example US EPA guidance ‘Radon in water sampling program’).
Select collection apparatus (for example a bailer or pump) – use pump only if content < 5% solid. Suction pumps are only recommended for depths of <8m. A submersible pump is required for deeper boreholes. Purge borehole (for example 3 borehole volumes or purge until water characterisation parameters such as pH, temperature, and dissolved oxygen stabilise). Rinse collection apparatus and container with sample. Collect representative sample.
Do not filter sample.
For all the water types: Minimise radionuclide adsorption to container walls by adding a carrier or preservative to water as appropriate (dependent upon the radionuclide). Store the sample to minimise growth of algae and prevent deterioration both in transit to the laboratory (such as cool dark conditions, cool box) and at the laboratory (for example chill at about 4ºC in the dark). Concentrate sample if needed (for example through ion exchange or evaporation).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: provide assurance.
Group 3:
- comply with international obligations
- assess background (very far field)
Group 4: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: 1 to 4 local milk producers reflecting modelled concentrations and wind-rose. For assessing long term trends and understanding the behaviour of radionuclides 1 to 2 milk producers based on wind-rose (difficult to achieve with changes in farming practices) and 1 location for check monitoring.
Group 2: 1 to 10 local producers from habit surveys such as local dairies, markets, producers from habit surveys and more distant farms (5 to 10km).
Group 3: 1 to 2 remote milk producers or as part of a national programme such as supermarket milk. For international obligations up to 35 locations for Great Britain.
Group 4: 1 to 4 local milk producers reflecting modelled concentrations and wind-rose.
Typical sampling frequencies
Group 1: Sampling up to weekly, monthly to quarterly bulks for analysis (nuclide dependent for example I-131 may require more frequent analysis). Needs to be all year round to take account of silage consumption during winter. For assessing long term trends and understanding the behaviour of radionuclides annual sampling and monthly to annually for check monitoring.
Group 2: Quarterly – annual spot or bulk samples (nuclide dependent for example I-131 may require more frequent analysis).
Group 3: Weekly sampling, monthly to annual bulks for analysis for a national programme or quarterly – annually (nuclide dependent) for assessing background.
Group 4: Monthly whilst cows grazing in field analysed for a limited number of radionuclides.
Programme ranges to meet all objectives
Overall: 5 to 88 samples per year from 1 to 10 locations for the main programme. Where relevant 6 to 24 samples analysed for a limited number of radionuclides from 1 to 4 local milk producers. Up to 420 from up to 35 locations as part of a national programme for background and international obligations.
Lower impact site: 4 to 16 samples per year from 1 to 4 locations.
Higher impact site: 16 to 88 samples per year from 4 to10 locations and where relevant 6 to 24 samples analysed for a limited number of radionuclides from 1 to 4 local milk producers to detect abnormal, fugitive, and non-permitted releases.
Data requirements
Reported as Bq/L. If results are reported as dry weight, then the fresh-dry weight ratio should be provided.
How to sample and prepare
Two methods of preparation: either the analysis of the raw edible fraction (such as milk collected directly from the farm) or via culinary preparation (in the case of milk this might mean for instance sampling processed butter).
Rinse collection apparatus and container with sample (if milk). Collect a representative sample of the source material. Consider the area over which cattle have been grazing, if taken at the farm, consider how many animals should be sampled or for example sampling from the tanker. Record the provenance of the sample to ensure traceability of the sample back to the field (links to representative nature of the sample).
Add carrier or preservative to milk as appropriate depending upon the radionuclide. Store the sample to prevent deterioration in transit to the laboratory (such as store in airtight containers, cool box).
Select a representative sub-sample for analysis (for example shake milk sample). Concentrate sample if needed (for example evaporation, ion-exchange, freeze drying).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: provide assurance.
Group 3: assess background (very far field).
Typical sampling locations
Group 1: 0 to 4 local producers and food types reflecting modelled concentrations and wind-rose. For assessing long term trends, understanding behaviour of radionuclides in the environment and check monitoring 0 to 1 meat producer and food type based on wind-rose (difficult to achieve with changes in farming practices).
Group 2: 0 to 4 local producers and food types from habit surveys such as local farm shops producers from habit surveys and more distant farms (5 to 10km).
Group 3: 0 to 2 remote meat producers and food types or as part of a national programme such as from farms or markets or indirectly through mixed diet programme.
Typical sampling frequencies
Group 1: For assessing representative dose quarterly to annually. Other objectives annually.
Group 2: Quarterly to annually.
Group 3: Annually.
Programme ranges to meet all objectives
Overall: 0 to 32 samples per year from 0 to 8 producers.
Lower impact site: 0 to 2 samples per year from 0 to 2 producers.
Higher impact site: 0 to 32 samples per year from 0 to 8 producers.
Data requirements
Reported as Bq/kg (fresh weight). If results are reported as dry weight, then the fresh-dry weight ratio should be provided.
How to sample and prepare
The approach outlined is for longer lived radionuclides that will still be present by the time the food product is available for human consumption.
Consider the need for local sampling versus retail sampling for national averages.
Identify sample type (such as from a mature animal that would be sold commercially or from roadkill or natural deaths to avoid culling) and determine a representative cut or part of the animal (such as the thigh, neck, breast) to ensure an edible fraction that would be consumed is selected, this may not be possible for roadkill. Select samples of muscle, liver, and kidney (where there is a market for offal such as from farmed animals) as these cover the main sites of radionuclide accumulation and are all consumed in significant quantities. Record the provenance of the sample to ensure traceability of the sample back to the field (links to representative nature of the sample).
Store the sample to prevent deterioration both in transit to the laboratory (for example store in airtight containers) and at the laboratory (for example chill at about 4ºC or freeze).
Prepare samples to provide edible fraction (may require culinary preparation depending upon the objective). Dry sample to constant weight (for example oven dry 40 to 105ºC or freeze-dry). Analyse fresh if detection limits can be achieved and a representative sub-sample can be taken or if volatile radionuclides are present.
Record fresh-dry ratio.
Select a representative sub-sample for analysis (for example by homogenising dry sample in mill or blender or mincing fresh sample – cone and quarter if appropriate).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- check or complementary monitoring
- assess long term trends (indicator)
Group 2: provide assurance.
Group 3: assess background (very far field).
Typical sampling locations
Group 1: 1 to 4 local producers and food types reflecting modelled concentrations and wind-rose. For assessing long term trends and check monitoring 1 local producer and food type based on wind-rose (difficult to achieve with changes in farming practices).
Group 2: 1 to 4 local producers and food types from habit surveys such as local farm shops producers from habit surveys and more distant farms (5 to 10km).
Group 3: 1 to 2 remote producers and food types or as part of a national programme such as from supermarkets.
Typical sampling frequencies
Group 1: For assessing representative dose quarterly to annually. Other objectives annually.
Group 2: Quarterly to annually.
Group 3: Annually.
Programme ranges to meet all objectives
Overall: 1 to 32 samples per year from 1 to 8 producers.
Lower impact site: 1 to 2 samples per year from 1 to 2 producers.
Higher impact site: 2 to 32 samples per year from 2 to 8 producers.
Data requirements
Reported as Bq/kg (fresh weight). If results are reported as dry weight, then the fresh-dry weight ratio should be provided.
How to sample and prepare
Approach outlined is for longer lived radionuclides that will still exist by the time the food product is available for human consumption.
Consider the need for local sampling versus retail sampling for national averages.
Identify sample type and select a representative cut or part of the food stuff (such the thigh or breast, from a mature bird that would be sold commercially and select the edible fraction).
Record the provenance of the sample to ensure traceability of the sample back to the field (links to representative nature of the sample).
Store the sample to prevent deterioration both in transit to the laboratory (for example store in airtight containers) and at the laboratory (for example chill at about 4ºC or freeze).
Prepare samples to provide edible fraction (may require culinary preparation depending upon the objective).
Dry sample to constant weight (for example air dry, oven dry 40 to 105ºC, freeze-dry). Analyse fresh if detection limits can be achieved and a representative sub-sample can be taken or if volatile radionuclides are present).
Record fresh-dry ratio.
Select a representative sub-sample for analysis (for example by homogenising dry sample in mill or blender, blending, whisking, or stirring eggs and honey or mincing fresh sample – cone and quarter if appropriate).
Example wild foods considered:
- apple
- bilberry
- blackberry
- cherry
- chestnut
- chive
- cobnut (hazelnut)
- crab apple
- damson
- dandelion
- elderberry
- elderflower
- garlic
- hawthorn berry
- horseradish
- mayflower
- mint
- mushroom
- nettle
- peppermint
- plum
- raspberry
- rose hip
- rowanberry
- sloe
- strawberry
- watercress
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- provide assurance (most measurements required for this objective)
- assess total representative person dose
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: assess background (very far field).
Typical sampling locations
Group 1: 1 to 4 local producers and food types (root veg, green veg, fruit, free foods) based on habit surveys and maximum deposition. The number of locations could increase to 1 to 10 to provide assurance with 1 to 2 local producers and food types used for check monitoring.
Group 2: 1 to 4 local producers and food types (root veg, green veg, fruit, free foods) or as part of a national programme.
Typical sampling frequencies
Group 1: Annual at point of harvest. For check monitoring annually to 3 yearly.
Group 2: Annual to 3 yearly.
Programme ranges to meet all objectives
Overall: 1 to 14 samples per year from 1 to 14 producers for the main programme. 1 to 50 samples as part of a national programme for background.
Lower impact site: 1 to 4 samples per year from 1 to 4 producers.
Higher impact site: 1 to 14 samples per year from 1 to 14 producers.
Data requirements
Reported as Bq/kg (fresh weight). If results are reported as dry weight, then the fresh-dry weight ratio should be provided.
How to sample and prepare
Approach outlined is for longer lived radionuclides that will still exist by the time the food product is available for human consumption.
Consider the need for local sampling versus retail sampling for national averages.
Identify sample type and remove any extraneous material from the sample collected.
Select a representative sample of the source material. When sampling in the field consider the location and size of area to be sampled (for example collect sample from the ends of a W or X shaped sampling pattern). When sampling sacks or boxes, after harvesting, determine how many samples and which sacks or boxes to sample. For wild foods consider the number of plants to be sampled (such as for blackberries and other hedgerow species, sample from along a 10m length of hedge).
Record the provenance of the sample to ensure traceability of the sample back to the field (links to representative nature of the sample).
Store the sample to prevent deterioration both in transit to the laboratory (for example store in airtight containers) and at the laboratory (for example chill at about 4ºC or freeze).
Prepare samples to provide edible fraction (may require culinary preparation depending upon the objective).
Dry sample to constant weight (for example air dry, oven dry 40 to 105ºC, freeze-dry). Analyse fresh if detection limits can be achieved and a representative sub-sample can be taken or if volatile radionuclides are present).
Record fresh-dry ratio.
Select a representative sub-sample for analysis (for example by homogenising dry samples in mill or blender, blending, whisking, or mincing fresh samples – cone and quarter if appropriate).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- check or complementary monitoring
- assess long term trends (indicator)
Group 2: assess background (very far field).
Typical sampling locations
Group 1: 1 to 2 local producers and food types.
Group 2: 1 to 2 remote producers and food types or as part of a national programme such as from farms or markets.
Typical sampling frequencies
Group 1: Annually at point of harvest. For check monitoring annually to 3 yearly.
Group 2: Annual to 3 yearly.
Programme ranges to meet all objectives
Overall: 1 to 2 local producers and food types per year.
Lower impact site: 0 to 1 local producers and food types per year.
Higher impact site: 1 to 2 local producers and food types per year.
Data requirements
Report results as Bq/kg (fresh weight). If results are reported as dry weight, then the fresh-dry weight ratio should be provided.
How to sample and prepare
Approach outlined is for longer lived radionuclides that will still exist by the time the food product is available for human consumption. Usually sample mature grain, however, if looking to understand distribution of activity in the field, any stage of the crop may be sampled and analysed fresh and immediately to detect short lived radionuclides.
Consider the need for local sampling versus retail sampling for national averages.
Identify cereal type.
Sample the material at an appropriate time (such as mature grain straight from the field, as grain that has been harvested or as bread).
Select a representative sample of the source material. When sampling in the field consider the location and size of area to be sampled (for example in the field collect sample from the ends of a W or X shaped sampling pattern). When sampling grain from sacks after harvesting, consider how many samples and which sacks to sample.
Record the provenance of the sample to ensure traceability of the sample back to the field (links to representative nature of the sample).
Store the sample to prevent deterioration both in transit to the laboratory (for example store in airtight containers) and at the laboratory (for example chill at about 4ºC or freeze).
Prepare samples to provide edible fraction (may require culinary preparation depending upon the objective).
Dry sample to constant weight (for example air dry, oven dry 40 to 105ºC, freeze-dry), but analyse fresh for volatile radionuclides.
Record fresh-dry ratio.
Select a representative sub-sample for analysis (for example by homogenising dry samples in mill or blender or blending fresh samples – cone and quarter if appropriate).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total impact on wildlife (most measurements required for this objective)
- provide assurance (most measurements required for this objective)
- check or complementary monitoring
Group 2:
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 3: assess background (very far field).
Typical sampling locations
Group 1: For assessing impact on wildlife and providing assurance 1 to 5 locations targeted to sensitive wildlife habitats, population centres and point of predicted maximum deposition. For check monitoring use the location at the point of maximum deposition.
Group 2: 1 to 2 fixed locations – point of maximum concentration, prevailing wind direction.
Group 3: 1 to 2 remote locations or as part of national programme (such as on 50km grid across UK approximately 150 samples every 10 years).
Typical sampling frequencies
Group 1: Annually, or annually to 3 yearly for providing assurance and check monitoring.
Group 2: Annually.
Group 3: 3 yearly to 10 yearly.
Programme ranges to meet all objectives
Overall: 2 to 5 samples per year from 2 to 5 locations. Up to 150 samples as part of national programme for background every 10 years.
Lower impact site: 2 samples per year from 2 locations.
Higher impact site: 2 to 5 samples per year from 2 to 5 locations.
Data requirements
Reported as Bq/kg (dry weight) with the wet-dry ratio, for objectives assessing background, long term trends and understanding the behaviour of radionuclides also report as Bq/m2 (dry weight).
How to sample and prepare
Group 1 and 3 objectives: Samples should be collected from undisturbed permanent pasture. Remove surface litter and overlying vegetation. The area may be fenced off to protect the collection site.
Samples of soil in the root zone should be collected to a known depth (typically 2 to 5cm), whilst minimising excessive damage to the collection site. This may be achieved by collecting 4 to 10cm diameter cores to a depth of 5cm. It is normal to remove roots as far as reasonably practicable from the sample. However, it may be appropriate to include all the roots in the sample in certain circumstances.
Obtain a reasonably representative sample over a scale of up to 5 to 10m. This may be achieved by collecting 5 soil samples from the points of a W shape or the ends and centre of an X shape over a circle of 10m diameter. The samples may be bulked.
Store the sample to prevent degradation and loss of volatiles (if appropriate) both in transit to the laboratory (for example store in airtight containers) and at the laboratory (for example chill at about 4ºC or freeze).
Dry sample to constant weight and preventing fusing of sample (for example oven dry 40 to 105ºC or freeze dry). May need to analyse wet for volatile radionuclides.
Record wet-dry ratio.
Remove gravel component by sieving to <2mm and discarding >2mm fraction.
Ensure representative sub-sample is taken for analysis (for example by grinding and coning and quartering).
Group 2 objectives: As for other objectives except sampling should be to a greater depth (typically 15cm).
Section core into slices which enable the monitoring objectives to be achieved. Account may need to be taken of compression of the core, particularly for wet soils. There is no need to section cores where the total deposition is being established for a baseline. Cores are typically sectioned into 5 to 10cm slices. Clean core sectioning tool (blade) between slices.
Sub-sample from centre of each core slice to reduce smearing.
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- provide assurance (most measurements required for this objective)
- assess total representative person dose (using grass as a surrogate for milk)
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: assess background (very far field).
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: 1 to 5 targeted at population centres and, or maximum concentration (could also be at a location of an emergent issue). If using as a dose surrogate, also in the vicinity of where surrogate food type would have come from. For check monitoring and understanding the behaviour of radionuclides in the environment use the location at the point of maximum deposition. For assessing long term trends 1 to 3 fixed locations including at the point of maximum deposition and in the prevailing wind direction.
Group 2: 1 to 2 locations, or as part of national programme (such as on 50km grid across UK approximately 150 samples every 10 years).
Group 3: 1 to 5 locations including the location of maximum concentration.
Typical sampling frequencies
Group 1: Quarterly to annually. If using as a dose surrogate monthly to quarterly during the growing season – assumed 8 months. For check monitoring annually to 3 yearly.
Group 2: Annually to 10 yearly.
Group 3: Monthly to quarterly.
Programme ranges to meet all objectives
Overall: 2 to 20 samples per year from 2 to 5 locations. Up to 150 samples as part of national programme for background every 10 years.
Lower impact site: 2 to 8 samples per year from 2 locations.
Higher impact site: 2 to 20 samples per year from 2 to 5 locations.
Data requirements
Reported as Bq/kg (wet weight) with the wet-dry ratio, for objectives assessing background, long term trends, detecting abnormal fugitive or non-permitted releases and understanding the behaviour of radionuclides also report as Bq/m2 (wet weight).
How to sample and prepare
Samples should be collected at same location as soil samples if the objective is to validate dispersion, deposition, and transfer modelling.
Area may be fenced off to prevent removal of grass and unwanted additions (such as animal droppings, fertiliser). Also enables growth since last sample to be collected.
Obtain a reasonably representative sample over a scale of up to 5 to 10m from a known total area. This may be achieved by collecting 5 grass samples from a 0.25 to 1m2 quadrat at the points of a W shape or the ends and centre of an X shape over a circle of 10m diameter. Grass or herbage samples should be representative of that present at a scale of up to 5 to 10m. The samples may be bulked.
Trim sample approximately 10mm above soil surface with shears (or similar), taking care not to collect any soil and excluding non-herbage (such as woody) material.
Store the sample to prevent degradation and loss of volatiles (if appropriate) both in transit to the laboratory (for example store in airtight containers) and at the laboratory (for example chill at about 4ºC or freeze).
Dry sample to constant weight and preventing fusing of sample (for example oven dry 40 to 105ºC or freeze dry). May need to analyse wet for volatile radionuclides.
Record wet-dry ratio.
Ensure representative sub-sample is taken for analysis (for example use blender).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- provide assurance
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: assess background (very far field).
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: 1 to 2 edible species, indicator of edible species or part of food-chain based on habit surveys, maximum concentrations, and availability of species. For providing assurance up to 4 edible species, including if local concern.
Group 2: 1 to 2 remote locations.
Group 3: 1 to 4 locations, cover different species.
Typical sampling frequencies
Group 1: Quarterly to annually for dose objective, annually for others, except for check monitoring annually to 3 yearly targeted against lifecycle of the weed.
Group 2: Annually to 3 yearly, targeted against life cycle of weed.
Group 3: Monthly to quarterly analysed for a limited number of radionuclides.
Programme ranges to meet all objectives
Overall: 1 to 10 samples per year (4 to 48 limited radionuclides) from 1 to 4 locations.
Lower impact site: 0 to 2 samples per year from 0 to 2 locations.
Higher impact site: 1 to 10 per year (4 to 48 limited radionuclides) from 1 to 4 locations.
Data requirements
Reported as Bq/kg (wet weight).
How to sample and prepare
Correctly identify single species (including hybrids) as determined to meet objective. May need to be a food species (such as water cress).
Consider seasonal (annual) cycle on sampling strategy.
Collect and trim recent growth from plant or parts used for food (as applicable) according to local practice. Selection of recent growth for analysis will provide a better indicator of recent discharges than analysis of a whole plant which will lead to an indicator of integrated discharges over a few years.
Wash in water to remove particulates.
Store the sample to prevent degradation and loss of volatiles (if appropriate), both in transit to the laboratory (for example cool, dark conditions, cool box) and at the laboratory (for example chill at about 4ºC or freeze).
Dry sample to constant weight (for example air dry, oven dry 40 to 105ºC, freeze-dry), but analyse fresh for volatile radionuclides.
Record dry-fresh ratio.
Select a representative sub-sample for analysis (for example by homogenising dry sampled in mill or blender or blending fresh samples – cone and quarter if appropriate).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose
- provide assurance
- check or complementary monitoring
- understand or monitor behaviour of radionuclides in the environment
Group 2: assess total impact on wildlife.
Group 3: assess background (very far field).
Group 4: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: 0 to 4 local food types reflecting maximum concentrations and habit surveys. Local farm shops and butchers should be considered for providing assurance and for understanding the behaviour of radionuclides use the food type reflecting maximum concentration.
Group 2: 0 to 4 species reflecting maximum concentrations – only adventitious finds.
Group 3: 0 to 2 remotely sourced food types or as part of a national programme.
Group 4: 0 to 2 species found on or close to site – only adventitious finds.
Typical sampling frequencies
Group 1: Annually, except for check monitoring annually to 3 yearly.
Group 2: Annually (as available).
Group 3: Annually to 3 yearly.
Group 4: Monthly to quarterly (only if adventitious finds available) analysed for a limited number of indicator radionuclides.
Programme ranges to meet all objectives
Overall: 0 to 10 samples per year (0 to 24 limited radionuclides).
Lower impact site: 0 to 2 samples per year.
Higher impact site: 0 to 10 samples per year (0 to 24 limited radionuclides).
Data requirements
Reported as Bq/kg (wet weight).
How to sample and prepare
Select species for required sampling, note however, for some objectives there may only be ad hoc monitoring or monitoring based on sample availability rather than routine targeted sampling.
Correctly identify species and collect roadkill or cull if needed (bearing in mind the legal protection afforded to some species) or sample faeces or live monitor. If faeces collected, then guidance on storage and preparation of sewage sludge should be considered.
Record the provenance of the sample to ensure traceability of the sample back to the field (links to representative nature of the sample).
Store the sample to prevent deterioration both in transit to the laboratory (for example store in airtight container, cool box) and at the laboratory (for example chill at about 4ºC or freeze).
Prepare samples as whole (including entrails) OR prepare specific portion of sample (such as feathers).
Record weights of parts required for analysis and for discarded parts.
Dry sample to constant weight (for example oven dry 40 to 105ºC, freeze-dry). Analyse fresh if detection limits can be achieved and a representative sub-sample can be taken or if volatile radionuclides are present).
Record dry-fresh ratio.
Select a representative sub-sample for analysis (for example by homogenising dry sample in mill or blender or mincing fresh sample – cone and quarter if appropriate).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose
- provide assurance (landfill operatives considered here)
- check or complementary monitoring
- assess long term trends (indicator)
Group 2: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: At central collection point prior to disposal such as to sewer or tanker.
Group 2: 1 to 4 leachates from affected disposal cells and at central point of collection.
Typical sampling frequencies
Group 1: Quarterly to annually, with annual for assessing long term trends and check monitoring.
Group 2: Monthly to quarterly analysed for a limited number of indicator radionuclides.
Programme ranges to meet all objectives
Overall: 1 to 4 samples per year (4 to 48 limited radionuclides).
Lower impact site: 0 to 1 sample per year.
Higher impact site: 1 to 4 samples per year (4 to 48 limited radionuclides).
Data requirements
Reported as Bq/l and Bq/m3 for dissolved and particulate phases and kilogram per litre (kg/l) particulate if appropriate.
How to sample and prepare
Detailed guidance on collection of samples from boreholes is available such as Environment Agency guidance on the ‘Monitoring of landfill leachate, groundwater and surface water’ and ISO 5667-11: ‘Water quality sampling – part 11: guidance on sampling of groundwater’.
Determine sample collection depth based on monitoring requirements.
Select collection apparatus (for example a bailer or pump) – use pump only if content < 5% solid. Suction pumps are only recommended for depths less than 8m. A submersible pump is required for deeper boreholes.
Purge borehole (3 borehole volumes) and rinse collection apparatus and container with leachate prior to taking the sample.
Collect representative sample.
Store the sample to minimise growth of algae and prevent deterioration both in transit to the laboratory (for example cool dark conditions) and at the laboratory (for example chill at about 4ºC or freeze in the dark).
Filter samples through a 0.45µm membrane and analyse filtrate and residue if the monitoring objective requires information on the partitioning between dissolved and particulate phases (such as migration of leachate into groundwater).
Ensure representative sub-sample is taken for analysis (for example shake liquid samples).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- provide assurance
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: assess background (very far field).
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: 3 sampling points (raw sewage entering works, treated effluent prior to discharge and final sludge prior to disposal). Raw sewage not required for providing assurance or understanding the behaviour of radionuclides. For dose objective also 1 to 4 locations capturing sludge and effluent throughout process, these to be used for workforce reassurance too.
Group 2: 1 to 2 remote sewage works 3 sampling points (raw sewage entering works, treated effluent prior to discharge and final sludge prior to disposal).
Group 3: 2 sampling points (raw sewage entering works and final sludge prior to disposal).
Typical sampling frequencies
Group 1: Quarterly to annually, with annually for public, stakeholder and workforce reassurance, assessing long term trends and check monitoring.
Group 2: 3 yearly to 10 yearly.
Group 3: Monthly to quarterly analysed for a limited number of indicator radionuclides.
Programme ranges to meet all objectives
Overall: 4 to 30 samples per year (8 to 24 limited radionuclides).
Lower impact site: 4 to 16 samples per year.
Higher impact site: 4 to 30 samples per year (8 to 24 limited radionuclides).
Data requirements
Reported as Bq/L and Bq/kg as appropriate, with the wet-dry ratio and suspended solids content.
How to sample and prepare
Health and Safety: Working with Sewage guidance is available from the HSE.
Collect sample in a container which minimises any offensive smell.
Grab sampling for an environmental programme: for liquid samples rinse the collection apparatus and container with effluent prior to taking the sample. For solid or sludge samples, with high solids content, place directly into the container without pre-rinsing. Ensure containers are sealed and any appropriate biohazard markings applied.
Compliance programme sampling would be expected to be undertaken using temperature controlled automated samplers, with MCERTS certification, providing 24-hour composite samples.
Store the sample to prevent degradation and loss of volatiles (if appropriate), both in transit to the laboratory (for example cool, dark conditions, cool box) and at the laboratory (for example chill at about 4ºC or freeze).
Dry sample to constant weight and preventing fusing of sample (for example oven dry 40 to 105ºC in a well-ventilated oven or freeze dry). May need to analyse wet for volatile radionuclides or if smell is too offensive to allow drying.
Record wet-dry ratio.
Ensure representative sub-sample is taken for analysis (for example shake liquid samples).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- assess total impact on wildlife
- provide assurance
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2:
- comply with international obligations
- assess background (very far field)
Typical sampling locations
Group 1: At least 1 round and 1 flat fish (pelagic and benthic when assessing impact on wildlife). For check monitoring 1 of these alternating if possible. Ideally caught within 20km radius of site, landed at local ports, or sourced from local suppliers. Also consider farmed fish affected by discharges.
Group 2: For international obligations 4 locations per year with a range of fish types. For assessing background at least 1 round, 1 flat fish per year remote from site, or as part of a national programme.
Typical sampling frequencies
Group 1: For assessing representative dose and understanding behaviour of radionuclides quarterly to annually. Other objectives annually, except for check monitoring annually to 3 yearly.
Group 2: To comply with international obligations quarterly to annually. Assessing background every 1 to 3 years.
Programme ranges to meet all objectives
Overall: 2 to 10 samples per year. With potentially 4 to 16 as part of a national programme for background and international obligations.
Lower impact site: 2 to 4 samples per year (from 1 to 2 locations).
Higher impact site: 4 to 10 samples per year (from 1 to 3 locations).
Data requirements
Reporting units Bq/kg fresh weight. Also wet-dry ratio.
How to sample and prepare
Select and correctly identify species to meet monitoring objective (for example benthic versus pelagic, stage of growth, availability in the fishing ground).
Catch by net or line.
Store the sample to prevent degradation and loss of volatiles (if appropriate), both in transit to the laboratory (for example cool, dark conditions, cool box) and at the laboratory (for example chill at about 4ºC or freeze).
Prepare the raw edible fraction for analysis. Culinary preparation may need to be considered.
Dry sample to constant weight (for example oven dry 40 to 105ºC, freeze-dry), but analyse fresh for volatile radionuclides.
Record wet-dry ratio.
Select a representative sub-sample for analysis. (For example by homogenising dry sample in mill or blending fresh samples – cone and quarter if appropriate.)
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- assess total impact on wildlife
- provide assurance
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2:
- comply with international obligations
- assess background (very far field)
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: 1 to 4 crustaceans and molluscs (different species where possible) at locations based on habit surveys and maximum concentrations (such as known harvesting beds, local suppliers). For providing assurance also consider any local concerns and sampling in both directions from the discharge pipeline. For check monitoring, assessing long term trends and understanding the behaviour of radionuclides 1 to 2 crustaceans and molluscs at location of maximum concentration both directions from pipeline.
Group 2: To comply with international obligations, nationally 9 locations for a range of molluscs and crustaceans. Assessing background 1 to 2 crustaceans and molluscs remote from site or as part of a national programme.
Group 3: 1 to 2 crustaceans and molluscs at location of maximum concentration both directions from pipeline.
Typical sampling frequencies
Group 1: For assessing representative dose quarterly to annually. Other objectives annually, except for check monitoring annually to 3 yearly.
Group 2: To comply with international obligations quarterly – annually. Assessing background annually to 3 yearly.
Group 3: Monthly to quarterly analysed for a limited number of indicator radionuclides.
Programme ranges to meet all objectives
Overall: 2 to 18 samples per year from 1 to 6 locations for the main programme, with 9 to 36 samples as part of a national programme for background and international obligations. Also 4 to 24 limited nuclides to detect abnormal, fugitive, and non-permitted emissions.
Lower impact site: 2 to 8 samples per year.
Higher impact site: 8 to 18 samples per year. Also 4 to 24 limited nuclides to detect abnormal, fugitive, and non-permitted emissions.
Data requirements
Reporting units Bq/kg fresh weight. Also wet-dry ratio.
How to sample and prepare
Select and correctly identify species to meet monitoring objective.
Collect by hand sampling or using pots or digging as appropriate for species.
Do not depurate.
Store the sample to prevent degradation and loss of volatiles (if appropriate), both in transit to the laboratory (for example cool, dark conditions, cool box) and at the laboratory (for example chill at about 4ºC or freeze).
Prepare the raw edible fraction for analysis. Culinary preparation may need to be considered.
Dry sample to constant weight (for example oven dry 40 to 105ºC, freeze-dry), but analyse fresh for volatile radionuclides.
Record wet-dry ratio.
Select a representative sub-sample for analysis (for example by homogenising dry sample in mill or blending fresh samples – cone and quarter if appropriate).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- provide assurance (most measurements required for this objective)
- assess total representative person dose
- assess total impact on wildlife
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2: assess background (very far field).
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: For assessing representative person dose and assessing impact on wildlife 1 to 10 locations based on habit surveys, targeting sensitive wildlife and maximum concentrations. The number of locations could increase to 1 to 20 to provide assurance, targeting non-critical habits further afield and areas of local concern. For assessing long term trends, understanding the behaviour of radionuclides and check monitoring 1 to 3 locations considering the area of maximum predicted dose and locations in both directions from site.
Group 2: 1 to 2 remote locations per year or as part of a national programme.
Group 3: 1 to 6 locations per year, close to pipeline or modelled area of maximum impact in both directions from site.
Typical sampling frequencies
Group 1: Quarterly to annually, with annual for assessing the impact of wildlife, long term trends, understanding the behaviour of radionuclides and check monitoring.
Group 2: Once every 1 to 3 years.
Group 3: Monthly to quarterly analysed for a limited number of indicator radionuclides.
Programme ranges to meet all objectives
Overall: 1 to 80 samples per year (from 1 to 20 locations).
Lower impact site: 2 to 32 samples per year (from 2 to 8 locations).
Higher impact site: 8 to 80 samples per year (from 8 to 20 locations).
Data requirements
Reporting units Bq/kg dry weight. Also wet-dry ratio.
How to sample and prepare
Allow for tide times to ensure access.
Ensure depositional environment.
For freshwater sediment sample from exposed riverbed or banks of river (if regularly inundated). Use hand-held detectors to guide sampling.
Take samples from predominant sediment type.
Obtain a reasonably representative sample over a scale of up to 5 to 10m. This may be achieved by collecting 5 surface sediment samples from the points of a W shape or the ends and centre of an X shape over a circle of 10m diameter. For freshwater samples this may be achieved by selecting sampling positions from five points along the exposed riverbed or bank at distance of 1m apart. The samples may be bulked.
Collect surface sediment samples (0 to 1cm) with flat hand shovel (or appropriate tool) over selected area.
Store the sample to prevent degradation and loss of volatiles (if appropriate), both in transit to the laboratory (for example cool, dark conditions, cool box) and at the laboratory (for example chill at about 4ºC or freeze).
Dry sample to constant weight and preventing fusing of sample (for example oven dry 40 to 105°C or freeze dry). (May need to analyse wet for volatile radionuclides.)
Record wet-dry ratio.
Remove gravel component by sieving to <2mm and discarding >2mm fraction.
Ensure representative sub-sample is taken for analysis (for example by grinding and coning and quartering).
For some objectives may need to normalise or report factors which can influence concentrations (such as grain size (loss on ignition at 450°C a good proxy), total organic carbon) or restrict grain size (for example <250mm). More information available in technical reports on ‘Meso-scale variation of radionuclides in sediments and implications for sampling’ and ‘Micro-scale variability in contaminants in surface sediments’.
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- provide assurance (most measurements required for this objective)
- assess total impact on wildlife
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2:
- assess background (very far field)
- comply with international obligations
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: For providing assurance 1 to 4 locations based on non-critical habits, local concerns, close to pipeline and at modelled area of maximum impact. Both directions from site. To assess impact on wildlife 1 to 2 locations based on maximum concentrations and locations of sensitive wildlife. For check monitoring, assessing long term trends and understanding the behaviour of radionuclides use location of maximum concentration.
Group 2: 1 to 2 remote locations or as part of a national programme.
Group 3: 1 to 4 locations close to pipeline and to modelled area of maximum impact. Both directions from site.
Typical sampling frequencies
Group 1: Annually.
Group 2: To comply with international obligations monthly and to assess background 3 yearly to 10 yearly.
Group 3: Monthly to quarterly analysed for a limited number of indicator radionuclides.
Programme ranges to meet all objectives
Overall: 1 to 4 samples per year from 1 to 4 locations with 2 to 24 as part of a national programme for background and international obligations. Also 4 to 48 limited radionuclides.
Lower impact site: 1 sample per year.
Higher impact site: 1 to 4 samples per year from 1 to 4 locations.
Data requirements
Report as Bq/L for filtrate (or unfiltered samples), Bq/kg for particulate and include information on suspended solid content as kg/L.
How to sample and prepare
Beach collection of seawater samples.
Allow for tide times to ensure access.
Minimise adsorption of radionuclides to container (such as pre-soak containers and use carrier solutions). Rinse collection apparatus and container with sample.
Collect water (use water submersible pump for large volume samples or bucket or carboy for small volume samples). Continuous automatic sampling maybe required.
Store the sample to minimise growth of algae and prevent deterioration both in transit to the laboratory (for example cool dark conditions, cool box) and at the laboratory (for example chill at about 4ºC in the dark). Preserve with nitric acid for long storage (analysis dependant).
Filter samples through a 0.45µm membrane and analyse filtrate and residue if the monitoring objective requires information on the partitioning between dissolved and particulate phases.
Ensure representative sub-sample is taken for analysis (for example shake water sample). Concentrate sample if needed (for example through ion exchange or evaporation).
Objectives
The objectives can be grouped into those that can be met by the same set of samples and those that require discrete other sets of samples.
Group 1:
- assess total representative person dose (most measurements required for this objective)
- provide assurance
- check or complementary monitoring
- assess long term trends (indicator)
- understand or monitor behaviour of radionuclides in the environment
Group 2:
- assess background (very far field)
- comply with international obligations
Group 3: detect abnormal, fugitive, and non-permitted releases (indicator).
Typical sampling locations
Group 1: For providing assurance 1 to 10 locations and for other objectives 1 to 4 locations including where seaweed is consumed or used as fertiliser, based on habit surveys and availability of species, except 1 location for check monitoring. To assess long term trends and understand behaviour of radionuclides cover different species.
Group 2: 1 to 2 remote locations or as part of a national programme such as 1 to 10 locations for the UK.
Group 3: 1 to 4 locations, cover different species.
Typical sampling frequencies
Group 1: Quarterly to annually except for providing assurance and check monitoring, which is annually, targeted against lifecycle of seaweed.
Group 2: To comply with international obligations annually and to assess background annually to 3 yearly, targeted against life cycle of seaweed.
Group 3: Monthly to quarterly analysed for a limited number of radionuclides.
Programme ranges to meet all objectives
Overall: 1 to 22 samples per year from up to 10 locations with 1 to 10 as part of a national programme for background and international obligations. Also 4 to 48 limited radionuclides.
Lower impact site: 1 to 16 samples per year from 1 to 4 locations.
Higher impact site: 4 to 22 samples per year from 4 to 10 locations.
Data requirements
Report as Bq/kg wet weight.
How to sample and prepare
Consider seasonal (annual) cycle on sampling strategy.
Selection of recent growth for analysis will provide a better indicator of recent discharges than analysis of a whole frond which will lead to an indicator of integrated discharges over a few years.
Allow for tide times to ensure access (for beach collection).
Correctly identify single species (including hybrids) as determined to meet objective. May need to be a food species.
Collect and trim recent growth from fronds or parts used for food or compost (as applicable) according to local practice.
Note presence of fruiting bodies which may affect results, due to changes in plant physiology.
Wash in water to remove particulate and epiphytes (unless to represent use as compost).
Store the sample to prevent degradation and loss of volatiles (if appropriate), both in transit to the laboratory (for example cool, dark conditions, cool box) and at the laboratory (for example chill at about 4ºC or freeze).
Dry sample to constant weight (for example air dry, oven dry 40 to 105ºC, freeze-dry), but analyse fresh for volatile radionuclides.
Record wet-dry ratio.
Select a representative sub-sample for analysis (for example by homogenising dry sampled in mill or blender or blending fresh samples, cone, and quarter if appropriate).
The Environment Agency is open to innovation in environmental radiological monitoring and below is a selection of examples of some areas of active development. Note we do not advocate these technologies as best available techniques (BAT). We are happy to discuss proposals from operators on innovations, particularly where this may not fully align with this guidance.
Drones and robotic technology
Drones and robots are being developed for radiological mapping following an incident or for use with decommissioning projects.
For example the IAEA has developed a system with instrumentation and a methodology for using unmanned aerial vehicles (UAVs) equipped with radiation detectors, cameras, and GPS devices. This has been tested and validated under real conditions in the Fukushima Prefecture in Japan and is now available for practical use in routine or emergency situations.
Also, in Belgium drones are being developed to be used as part of a monitoring programme, or during decommissioning projects or emergency planning, to carry out radiological measurements without any human intervention.
With development, similar systems could form part of the methodology for undertaking dose rate and contamination monitoring and we are aware of some UK nuclear operators considering the development of such robotic platforms.
Laser ablation
Laser ablation is a solid sampling technique that uses short pulses of high intensity light to convert a solid sample directly into an aerosol, that can then be transferred for analysis, typically by inductively coupled plasma mass spectrometry (ICP-MS). The sampling area for laser ablation is small: maximum spot sizes are typically 200µm, thus sample homogeneity is an issue, but it has the advantage that no sample preparation is required.
Currently this technique would not be practical for use in an environmental monitoring programme, but steps are being made using laser sampling heads for sampling radioactively contaminated building/waste materials with larger sample sizes (~2g) and counting using portable high resolution gamma spectrometry. There may be potential for future progress into the realms of environmental sampling and analysis.
In-situ real-time monitoring
Technologies are developing where mobile analytical facilities could be deployed in the field and there is movement towards developing widespread autonomous nano radiation monitoring (currently more safety and security applications), taking advantage of the ‘internet of things’. In future these may be tools that can be deployed for environmental monitoring.
Digital
With broader developments in digital technologies, there is the potential for innovation in a number of aspects of how environmental radiological monitoring data and information are managed, assessed, reported and stored.