Environmental Monitoring and Effluent Control
Effluent control
Gaseous and liquid discharges are controlled through authorised limits, derived from dose assessment to the critical group. Know the concepts of the critical group, the source-pathway-receptor model, and the difference between authorisation limits and notification/action levels. Effluents are monitored before discharge, with hold-up and sampling to confirm compliance.
Environmental monitoring
Monitoring programmes combine source monitoring, environmental monitoring (air, water, soil, biota) and, where relevant, personal monitoring. Baseline data collected before operations are essential to distinguish facility impact from background. Know the difference between a surveillance programme (confirmatory) and a research programme.
Traps
- Confusing discharge concentration limits with total activity limits.
- Ignoring the critical group's habits (e.g. consumption of local fish or milk).
- Treating a single elevated result as proof of a trend - check counting statistics and background variation.
- Forgetting that monitoring must include non-radiological parameters where relevant.
Rule of thumb
Dose assessment to the critical group, not average population dose, sets discharge limits.
Worked example
A liquid discharge limit is 10 GBq per year. A facility discharges 0.5 GBq per month. Annual total is 6 GBq, below the limit, but monthly peaks must also be checked against any monthly limit in the authorisation.