The atmosphere is a major transfer path of pollutants released in gaseous form or in aerosols form from an industry to the land and/or sea environment and, consequently, to humans. In order to estimate the impacts of an atmospheric release on human and on the environment, it is necessary to assess the dispersion and deposition (wet and dry) of these pollutants. Dry deposition was studied from experimental campaigns carried out in situ and in laboratory which allowed understanding globally the phenomena governing it. However, it still remains uncertainties as for the assessment of dry deposition velocity, in particular for submicronic and micronic aerosols. The dry deposition velocity depends on numerous factors such as micro-meteorological conditions, pollutant and substrate properties. This implies that dry deposition velocity cannot be accurately assessed without in situ measurements. Generally, a conservative value of 5 10-3 m.s-1 is used in operational models due to a lack of specific knowledge of the site being studied. On May 18th, 2001, the spent fuel reprocessing plant of COGEMA La Hague released into the atmosphere, Ruthenium and Rhodium-106 (106Ru-Rh) aerosols which marked the near environment of the site. Following this release, grass was sampled by different laboratories (GRNC, 2002) (Crabol and Maro, 2001) and the results obtained were analyzed (Maro et al., 2002). The purpose of this document is to show the results of 106Ru-Rh measurements carried out on grass, and the interpretation made regarding the operational deposition models.