PULP MILLS (JUDGMENT) 70 those rights include that of implementing the project, on the sole responsibility of that party, since the period for negotiation has expired. 156. In its Order of 13 July 2006, the Court took the view that the “construction [of the mills] at the current site cannot be deemed to create a fait accompli” (Pulp Mills on the River Uruguay (Argentina v. Uruguay), Provisional Measures, Order of 13 July 2006, I.C.J. Reports 2006, p. 133, para. 78). Thus, in pronouncing on the merits in the dispute between the Parties, the Court is the ultimate guarantor of their compliance with the 1975 Statute. 157. The Court concludes from the above that Uruguay did not bear any “no construction obligation” after the negotiation period provided for in Article 12 expired on 3 February 2006, the Parties having determined at that date that the negotiations undertaken within the GTAN had failed (see paragraph 40). Consequently the wrongful conduct of Uruguay (established in paragraph 149 above) could not extend beyond that period. 158. Having established that Uruguay breached its procedural obligations to inform, notify and negotiate to the extent and for the reasons given above, the Court will now turn to the question of the compliance of that State with the substantive obligations laid down by the 1975 Statute. * * IV. SUBSTANTIVE OBLIGATIONS 159. Before taking up the examination of the alleged violations of substantive obligations under the 1975 Statute, the Court will address two preliminary issues, namely, the burden of proof and expert evidence. A. Burden of Proof and Expert Evidence 160. Argentina contends that the 1975 Statute adopts an approach in terms of precaution whereby “the burden of proof will be placed on Uruguay for it to establish that the Orion (Botnia) mill will not cause significant damage to the environment”. It also argues that the burden of proof should not be placed on Argentina alone as the Applicant, because, in its view, the 1975 Statute imposes an equal onus to persuade — for the one that the plant is innocuous and for the other that it is harmful. 161. Uruguay, on the other hand, asserts that the burden of proof is on Argentina, as the Applicant, in accordance with the Court’s longstanding case law, although it considers that, even if the Argentine position about transferring the burden of proof to Uruguay were correct, it would make no difference given the manifest weakness of Argentina’s 60