West of the SC 57 area is the deepwater acreage of Service Contract No. 58 (SC 58), the West Calamian. Covering an area of 13,440 square kilometers, the West Calamian block was awarded to PNOC EC by the DOE on January 12, 2006.

On July 17, 2006, PNOC EC signed a farm-in agreement with Nido Petroleum Philippines Pty. Ltd. (Nido), under which Nido acquires 50% participating interest in the project with PNOC EC retaining the remaining 50%.

Initial basin evaluation conducted by PNOC EC on SC 58 indicated a number of attractive deepwater exploration targets in several petroleum plays involving the proven Nido carbonates (e.g. Malampaya), Pagasa clastics (e.g. Galoc) and potential targets in the Syn-rift sequence.

During the latter part of 2006, the consortium acquired 3,184 line-kilometers of new 2D seismic data. The new data will then be used to augment the existing database to fully understand the petroleum system of the basin. A pseudo-3D seismic survey began in November 2007 and is expected to be completed in January 2008. This seismic acquisition campaign is being conducted to further mature the five prospects previously delineated from earlier acquired seismic data.