PULP MILLS (JUDGMENT) 77 to the environment and of the limitations inherent in the very mechanism of reparation of this type of damage” (GabčíkovoNagymaros Project (Hungary/Slovakia), Judgment, I.C.J. Reports 1997, p. 78, para. 140). 186. The Parties also disagree with respect to the nature of the obligation laid down in Article 36, and in particular whether it is an obligation of conduct or of result. Argentina submits that, on a plain meaning, both Articles 36 and 41 of the 1975 Statute establish an obligation of result. 187. The Court considers that the obligation laid down in Article 36 is addressed to both Parties and prescribes the specific conduct of co-ordinating the necessary measures through the Commission to avoid changes to the ecological balance. An obligation to adopt regulatory or administrative measures either individually or jointly and to enforce them is an obligation of conduct. Both Parties are therefore called upon, under Article 36, to exercise due diligence in acting through the Commission for the necessary measures to preserve the ecological balance of the river. 188. This vigilance and prevention is all the more important in the preservation of the ecological balance, since the negative impact of human activities on the waters of the river may affect other components of the ecosystem of the watercourse such as its flora, fauna, and soil. The obligation to co-ordinate, through the Commission, the adoption of the necessary measures, as well as their enforcement and observance, assumes, in this context, a central role in the overall system of protection of the River Uruguay established by the 1975 Statute. It is therefore of crucial importance that the Parties respect this obligation. 189. In light of the above, the Court is of the view that Argentina has not convincingly demonstrated that Uruguay has refused to engage in such co-ordination as envisaged by Article 36, in breach of that provision. 4. The obligation to prevent pollution and preserve the aquatic environment (Article 41) 190. Article 41 provides that : “Without prejudice to the functions assigned to the Commission in this respect, the parties undertake : (a) to protect and preserve the aquatic environment and, in particular, to prevent its pollution, by prescribing appropriate rules and [adopting appropriate] measures in accordance with applicable international agreements and in keeping, where rele67