On 20 April 2010 the International Court of Justice (ICJ) in The Hague delivered its judgment in the case of Pulp Mills on the River Uruguay (Argentina v. Uruguay). The dispute concerns the construction of a pulp mill by Uruguay on the River Uruguay. Argentina had argued the Uruguayan pulp mills were pumping dangerous waste into the mutual river on the border between the two countries.
The proceedings relate to the 1975 Statute of the River Uruguay between Argentina and Uruguay on co-operation on the mutual river. The Court held that Uruguay should have informed Argentina about its plans to build the two pulp mills, in accordance with the treaty regulating the use of the river. It held that Uruguay had breached the 1975 treaty for failing to negotiate and for failing to inform the Administrative Commission of the River Uruguay (CARU), a commission established by the 1975 treaty. It held therefore that:
“Uruguay, by not informing CARU of the planned works before the issuing of the initial environmental authorizations for each of the mills and for the port terminal adjacent to the Orion (Botnia) mill, has failed to comply with the obligation imposed on it by Article 7, first paragraph, of the 1975 Statute” (para. 111).
However, it held that declaration of the breach constitutes appropriate satisfaction for the procedural breach. It found that ordering the dismantling of the mill or ordering compensation would be an inappropriate remedy for a breach of a procedural obligation.
Although it breached procedural obligations under the treaty, the Court held, (eleven votes to three) that Uruguay had not breached substantive obligations under the 1975 treaty. The Court held that Argentina had provided insufficient evidence to prove that discharges from the mills have "caused harm to living resources or to the quality of the water of the ecological balance of the river." Turning to the question of whether Uruguay had committed a substantive breach of the treaty, the Court held that
“there is no conclusive evidence in the record to show that Uruguay has not acted with the requisite degree of due diligence or that the discharges of effluent from the Orion (Botnia) mill have had deleterious effects or caused harm to living resources or to the quality of the water or the ecological balance of the river since it started its operations in November 2007”.
The Court therefore found that based on the evidence submitted Uruguay has not breached its obligations under Article 41 of the treaty. The Court held that the pulp mill could therefore continue to operate.
Since the judgment was delivered, both sides have said that they will now work together to protect the River Uruguay.