Name of the Project
Grassy Mountain gold project.

Location
Near the western edge of the Snake River Plain, in eastern Oregon, in the US.

Project Owner/s
US-based precious metals exploration and development company Paramount Gold Nevada.

Project Description
The Grassy Mountain project is an underground gold and silver mining operation. The mine will use a mechanised cut-and-fill mining method, accessed through a decline and a system of internal ramps, with cemented rock fill used for backfill.

Production is estimated at 1 300 t/d to 1 400 t/d of material to feed a 750 t/d processing plant. Over the estimated 7.8-year life-of-mine, the project is anticipated to recover about 361 800 oz of gold and 424 800 oz of silver.

The processing method involves conventional unit operations. Gold and silver will be recovered through a carbon-in-leach recovery circuit, followed by elution in a pressurised Zadra-style circuit and electrowinning in the gold room to produce doré bars. 

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The project has a pretax net present value, at a 5% discount rate, of $134.9-million and an internal rate of return of 24.22%.

Capital Expenditure
Initial capital costs are estimated at $136.2-million.

Planned Start/End Date
Not stated.

Latest Developments
Oregon regulators have released a draft consolidated permit package for the project, marking the first time the state has advanced a mining development through its unified permitting framework, Paramount Gold Nevada has reported. 

The Oregon Department of Geology and Mineral Industries (DOGAMI) published the draft on behalf of all cooperating state agencies, the company said on December 8. The package covers construction, operations, closure and long-term monitoring for the planned underground gold mine in Malheur county.

The release initiates a public-review phase, with DOGAMI scheduling a hearing for January 29 in Vale, Oregon. Written comments will be accepted until February 6. After the comment period closes, the regulator may revise the package before issuing the final permits.

Key Contracts, Suppliers and Consultants
Ausenco Engineering Canada (feasibility study – processing and infrastructure design, as well as overseeing the metallurgical testing); Mine Development Associates (feasibility study – mineral resource estimate, mine planning and reserves estimation); Golder Associates (tailings storage facility); and EM Strategies (overseeing all environmental aspects of feasibility study).

Contact Details for Project Information
Paramount Gold, tel +1866481 2233 or email info@paramountnevada.com.