US Copper Corp. announced it has signed a drilling contract with Timberline Drilling Inc. to drill a minimum of 10,000 feet ("ft") at the Engels deposit, part of US Copper's Moonlight-Superior Copper Project in Plumas County, California. This drill program will target an 800 ft by 400 ft by 700 ft envelope of open-pit grade copper mineralization surrounding the historic underground Engels Mine.

This mineralization was initially recognized in underground drill holes during the 1915-1930 mining operation but was considered too low-grade for exploitation in an underground mine. More recent historical surface drilling, which was primarily focused on defining shallow copper oxide mineralization, encountered substantial thicknesses of good open pit grade copper sulfide mineralization: The Engels copper deposit is located about 6,000 ft (1,830 metres ("m")) east of Moonlight deposit and 11,000 ft (335 m) north of the Superior deposit. Engels was mined in the 1915-1930 period, yielding approximately 2.7 million tons at a grade of 2.2 % copper.

Mine workings are extensive and include many tens of thousands of feet of drifts, crosscuts, and stopes on ten levels accessed by adits and six levels accessed from a winze sunk from the No. 10 level. Geologically, the Engels deposit lies outside the eastern margin of the Lights Creek quartz monzonite stock in an area of gabbroic intrusives and metavolcanic roof pendants.

Engels is structurally-controlled in a shear zone striking northeast and dipping steeply. Mined and processed ore occurs in an 800 ft by 60 ft (240 m by 20 m) pipe like zone and is associated with breccias that exhibit features characteristic of both intrusion and hydrothermal breccia. Narrow high-grade ore shoots were mined to depths of up to 2,000 ft (600 m), and historical drilling indicates that good grade mineralization extends at least another 300 ft (91 m) down ~2,300 ft (670 m) below surface (16th level).

The principal sulfide ore minerals are bornite and chalcopyrite, and copper grades exceeding 15% Cu have been encountered in several 6.5 ft (2 m) core intercepts. Remaining known significant copper mineralization from historical workings and drill holes varies from 0.2% Cu to well over 1.0%.