Abstract

The Longos Gold mine is a 500 TPD underground, narrow-vein, gold mine located at Paracale, Camarines Norte, Philippines.

In March 1983, shaft sinking operations encountered a water flow of 850 GPM at a depth 257 m which flooded the Mainshaft and disrupted shaft sinking operations. Recovery efforts by former mine owners were unsuccessful and shaft sinking operations were abandoned.

 

Hoist buildings and headframe of Mainshaft being grouted and sunk to a final depth of 1600 feet

In 1994, UNITED PARAGON MINING CORPORATION dewatered the Mainshaft to a depth of 240 m through underground development openings from adjacent mine workings.

Preparations to stop the 850 GPM water flow into the bottom of the Mainshaft commenced in June 1995.

Shaft bottom grouting operations commenced in January 1996.

By September 1996, the shaft had been successfully grouted and sunk through water-bearing faulted and altered rock to a depth of over 300 m.

Shaft sinking bucket used to deliver crew and equipment to shaft bottom