Environmental radiological surveillance in Spain

Radiological surveillance consists of evaluating and monitoring the environmental radiological impact of nuclear and radioactive sites, as well as the radiological quality of the environment throughout the national territory.

For this purpose, the Spanish Nuclear Safety Council (CSN) uses a system of networks and radiological surveillance programs.

Their main goals are the following:

• Detect the presence and monitor the evolution of radioactive elements and environmental radiation levels.
• Determine the causes of the possible increments of radioactive levels in the environment.
• Calculate the potential radiological risk for the population and, in this case, establish the proper precautions and measures.
• Verify compliance with the requisites set by the site authorizations.
• Guarantee compliance with the legal and regulatory requisites imposed on the sites.
• Verify the suitability of the effluent surveillance program (so that any undetected leaks may be detected) and the transference models of radionuclides in the environment.

This system is integrated with several surveillance networks:

Radiological surveillance network around nuclear power plants and sites in the nuclear fuel cycle

Environmental Radiological Surveillance Programs (PVRA) are managed by the owners of nuclear sites, and the CSN establishes the requisites that these owners must comply with in the surroundings during the site's various life stages. The CSN carries out periodic inspections and establishes systematic control programs to guarantee that the area remains safe.

During the inspections, samples from the site's influence areas are collected. Most samples are collected in the main channels of transference of radioactive elements to the population. The surveillance system uses various safeguards, such as an analysis of the samples by two different labs to check the degree of concordance of the results obtained by both.

Every year, the site owners send the results of the PVRA to the Council. These results can be reviewed in the Map of Environmental Radiological Values (in Spanish).

National radiological surveillance network, not associated with sites related to the nuclear fuel cycle (REVIRA)

This network makes it possible to get to know the radioactivity levels in the air, water, and soil of basic food such as milk and a complete diet. It is composed of a Network of Automatic Stations (REA) that survey atmospheric radiation in real-time. It is integrated by automatic stations with instrumentation to carry out a continuous measurement of radiological variables (gamma dose index, radon concentration, radioiodines, alpha and beta emitters in the air) and weather variables (temperature, relative humidity, wind direction and speed, precipitation and atmospheric pressure).

The average daily gamma dose indexes of the automatic surveillance stations scattered around the Spanish territory can be accessed in the REA map of environmental radiological values (in Spanish). These stations are in operation since 1992.

Sampling station network (REM)

In REM, surveillance is carried out by taking samples and then doing a radiological analysis. The method is similar to that of PVRA, with the difference that the surveillance is done by CSN with the cooperation of a series of Spanish laboratories and institutions.

It is composed of two complementary networks: the dense network, with numerous points distributed around the territory, and the high-sensibility network, where measuring is done in very few points. Both networks carry out measures corresponding to two types of programs:

• The atmosphere and terrestrial environment surveillance program, to measure radioactivity in soils, drinking water, milk, and standard diet.
• The coastal and continental water environment surveillance program, inspects the radiological quality of rain waters in the various river basins, as well as of ocean water in different points of the coast.

The results may be viewed in the PVRA REM Map of environmental radiological values (in Spanish).

Specific environmental radiological programs

Apart from the aforementioned programs in surveillance networks, in Spain, there are also specific programs in areas with residual contamination due to past practices.

At these sites, the necessary measures to eliminate all contamination and risks have already been taken, but the yearly environmental radiological surveillance plans are still in place.