• This document shows a quite deficient situation concerning the existence of solid scientific basis about the relation “cause-effect” of the radiological exposures. This could affect in a direct manner the credibility and acceptability of its content and proposals. Assuming that the situation described corresponds to the known reality, the arguments offered in the document about the validity on the approximation proposed could be reinforced by references to the equivalent situation for other contaminants with similar probabilities of causing negative effects in the environment. • Possibly for very well founded reasons (look the above commentary), the document contains many “worries” and “cautions”, as well as specific sentences that describe what the document ”cannot be”. Although this approach may be the most logical and the most scientifically founded and despite the existing limitations on the scientific information, it would be suitable to reinforce the “positive” message supporting that the recommended approximation is solid and prudent enough as to be acceptable, even though there is room for improvement following the lines for the future that the document identify as the more advisable (The paragraph 362 and following don’t seem to be the most suitable on this sense). • The body of the document is very long on its Chapter dedicated to show the existing knowledge in the area of “effects” (in fact the complete document is very long). There are probably good reasons to do it this way as a mean to avoid a misunderstanding on the content of Chapter 6. Nevertheless, for presentational reasons, the possibility of preparing a new Annexe about the subject “effects” should be considered, keeping in the body of the document only the essential messages about it (including paragraph 355 about diversity, reliability and utility of the scientific information analyzed). • Paragraph 3 should be even more conclusive, because there is not only a lack of one universal, unique and simple definition, for “environmental protection”, but –as the document clearly captures- there exist much more other limitations and lacks to be able to establish and define a well based protection system, beginning with the lacks on the protection levels to be achieved. • Paragraph 15 that talks about the relation “exposure to dose”, should mention a much larger gap such as the one existing on the relation between the concentration of radioactive contain in several environmental vectors and components and the consequent effects. This relation obviously includes the existing one between “exposure” and “dose”. • In paragraph 62 and 63, the three exposure situations and its different characteristics (and even interest) should probably be debated a little more in this framework. For example, it is supposed that in the first phases of an emergency (emergency exposures) the interest in the environment will be low, while in case of the “planned exposures” it will be essential and in case of the “existing exposures” it could be outstanding and even critical from the point of view of the social acceptability. • It is very clear the need of doing an extreme simplification in the system proposed, as it is pointed out in paragraph 71. What is neither said nor debated is if, in doing so, the essence itself of the advices that are finally offered is questioned. It is not important whether or not there is missing information, but only if what is missing affects or not the basic aspects of the proposal made with the objectives and the accuracy levels desired. • In paragraph 342 and in an absolutely logical way, it is appealed the use of “background levels” as an additional tool to define some useful frames to make judgements. Nevertheless in some situations, the background levels can be so small that could be of limited utility. Finally, it is not clear if the reference “dose rate” only considers external dose or also the internal. • There are some doubts about Table 8, 9, 10 and 11: - It does not seem suitable to do “reliable” calculations of the “dose rates”, because general methods to do so have not been defined - It is not well understood the line of the “background level” because in point 6.2, appreciable bigger values in some cases, were mentioned. In fact, the references to “background” and its importance and usefulness would deserve some additional clarification. - There are too many boxes in the charts without information.