Semirara Mining and Power Corporation (SMPC), an integrated energy company, has successfully finished backfilling operations in Panian, once the largest open-pit mine in the Philippines. The company spent PHP 12.35 billion and 11.5 million man-hours to fill the pit with over 452 million bank cubic meters (bcm) of earth material, which is enough to fill 217,000 Olympic-size swimming pools. SMPC fully covered the pit in six years, way ahead of the original 10-year mine rehabilitation plan.

Panian mine, located on Semirara Island, spanned 400 hectares, with varying elevations ranging from 300 meters below sea level to 30 meters above sea level during its operation, which is roughly equivalent to the height of a 90-storey building.

With the backfilling phase completed, SMPC is now focused on developing a science-based plan for reforesting and restoring biodiversity in the area.

Over its 16-year mine life, Panian contributed significantly to the local economy, generating P12.7 billion in royalties for the government and the host communities of SMPC. Out of this total, P7.6 billion went to the national government. The Municipality of Caluya and Brgy. Semirara received P2.3 billion and P1.8 billion, respectively, while P1 billion was allocated to the Province of Antique.

SMPC's exceptional efforts in the rehabilitation of South Panian pit earned them the ASEAN Energy Award (Special Submission category) in September 2021. The rehabilitation process was recognized as the fastest of its kind and scale in the country.