UPDATE 1-Chile's CMPC weighs $4 billion pulp plant in Brazil

(Updates with additional detail from filing)

SAO PAULO, April 29 (Reuters) - Chilean pulpmaker CMPC has signed a deal with Brazil's southernmost state of Rio Grande do Sul to evaluate building a new pulp plant there, which would require $4 billion in investments, it said on Monday.

The new project would initially have the capacity to produce up to 2.5 million metric tons of bleached hardwood kraft pulp (BHKP) per year, CMPC said in a securities filing, adding that it could later be expanded.

The firm said the project would undergo technical and environmental studies before being presented to the CMPC board for vote in mid-2026.

Beyond the investment required for the plant itself, the project would also need $420 million for road infrastructure and $150 million to expand a port terminal and build another in the city of Rio Grande. (Reporting by Andre Romani; Editing by Kylie Madry and Brendan O'Boyle)