B&B proposes new mine in southern California

A new gold operation, the open pit, heap leach Castle Mountain project, is being proposed in southern California by B & B Mining of Vancouver, B.C.

According to a plan of operations filed with the U.S. Bureau of Land Management, B & B hopes to develop four open pit gold mines and produce more than 26 million tons of ore from five gold deposits.

The property is located in San Bernardino County’s Castle Mountains within the East Mojave National Scenic Area.

According to company representative Marion Ely II, a mining and reclamation consultant in California, almost 26 million tons of ore reserves have been established so far at three of the Castle Mountain project deposits — the Jumbo South, Lesley Ann and Oro Belle.

Drilling also is under way at the remaining two deposits, the Jumbo and the Mountain Top, and is expected to continue through at least 1988 to fully delineate total project reserves. He added that more than four million tons of reserves are expected at the Jumbo and Mountain Top deposits.

Currently, Ely said, 28 tons of ore will yield one ounce of gold, which translates into an average ore grade of 0.0357 oz of gold per ton. Minor amounts of silver also exist, he noted.

Ely explained that the company ultimately plans to have four open pit mines at the five deposits because the Lesley Ann and Jumbo South pits, to be located at the southern end of the property, will merge into one pit.

B & B now has submitted all necessary permit applications for the project, including an application for surface mining and reclamation with San Bernardino Cty., an application for heap leaching with the Colorado River Basin Regional Water Quality Control Board, and an application for an air pollution control permit with the Air Pollution Control District for the Desert.

In its proposed plan of operations, B & B noted that the East Mojave National Scenic Area currently is classified as a multiple- use area and has been the site of much gold mining and clay quarrying since the turn of the century.

The company proposes for its Castle Mountain project a processing rate of 2.8 million tons per year.

“The ore will be crushed, then placed on a leach pad underlain with an impermeable membrane. Weak cyanide solutions will be used to extract gold and silver from the ore. The leachate containing the precious metals will be pumped to a processing plant to recover the metals from solution. The solution is then restored to operating strength with fresh chemicals and recycled through the heaps, in a closed system,” the company explained.

Total capital costs of more than $16 million are anticipated, including mining equipment; crushing, leaching and gold recovery facilities; a series of water wells; and on-site power generation equipment.

The project is expected to employ between 125 and 150 workers and have a minimum life of 10 years.

According to the company, the Castle Mountain site is in the old Hart Mining District about 80 road miles from Las Vegas and consists primarily of unpatented lode, millsite and placer mining claims, along with three patented lode claims.

B & B began exploration in 1985, successfully located several large, low grade gold deposits, and then established its current 26 million tons of reserves by drilling a total of more than 112,000 ft of rotary drill holes.

Of the 26 million tons, the Jumbo South deposit contains about 8.8 million tons; the Lesley Ann, about 10.3 million tons; and the Oro Belle, 6.8 million tons.

The ore from these first three deposits has proven amenable to heap leaching, and B & B plans to have four leach pads, each covering 55 acres and able to accommodate 7.5 million tons of ore.

“The pads will be constructed, loaded and leached in stages, essentially one at a time. The pads, associated solution ponds and process plant will ultimately occupy approximately 273 acres and contain up to 30 million tons of leached ore,” the company pointed out.

Most of the waste material, B & B said, will go to dumps adjacent to the pits, with some waste rock used for haul roads, berms and flood protection.

Mining would be conducted five days a week with two shifts daily, while processing, leaching and recovery would take place on a continuous basis. In the initial years of operation, the company proposes to mine about 45,000 tons of ore and waste per day, with approximately 65 employees for pit operations, ore haulage, crushing and placement of ore on the leach pads. An additional 60 to 85 workers would be involved with heap leaching, processing and ancillary services.

“Ore will be transported about one mile from the open pit sites down to a portable crushing plant adjacent to the leach pads,” the company added, noting that two stages of crushing will reduce the ore to “a nominal minus 1.5-inch size.”

B & B’s extensive plan of operations also included detailed reclamation information, chapters on alternatives to the proposed project and impacts and mitigations, plus history of the Hart Mining District.

Ely said the company has yet to develop a firm construction and operation timetable, pending the blm’s decision on the plan of operations and receipt of necessary permits. From Pay Dirt magazine.