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Calico Resources USA Corp. - Grassy Mountain

Calico Resources USA Corp. (Calico) is proposing to construct an underground gold mine and an indoor processing facility on a site in Malheur County about 22 miles south-southwest of Vale. The site includes both private and public lands managed by the US Bureau of Land Management (BLM).


  • Oregon's Chemical Mining Rules apply to this project because cyanide is proposed for processing the gold. The processed tailings will be placed in a tailings disposal facility. This facility must be lined, capped, and designed to avoid any discharge to groundwater or surface waters. The impoundment will be capped and sealed upon completion. The overall project is being designed to avoid any discharge to surface or ground waters.
  • Under state law, The Department of Geology and Mineral Industries (DOGAMI) manages the consolidated application process for chemical mining permits. DOGAMI's mission is to provide earth science information and regulation to make Oregon safe and prosperous.
  • Permitting agencies involved in the consolidated application process include DOGAMI, Oregon Department of Environmental Quality (DEQ) and Oregon Water Resources Department (WRD). Depending on specific details related to mine construction and operation, permits from the Department of State Lands or the Oregon Health Authority may also be required. Other federal, state, or local regulations are also required, including local land use permitting.
  • Oregon law provides environmental performance standards that guide agencies' reviews. The intent is to minimize environmental damage through use of best available, practicable, and necessary technology and provide protection measures that are consistent with polices of the permitting agencies.
  • A wildlife protection plan will be required to ensure no overall loss of wildlife habitat and to meet the State requirement of an objective of zero wildlife mortality.
  • The permitting process provides multiple opportunities for the public and interested stakeholders to participate in reviewing and commenting on Calico's application and the consolidated permit requirements.

Project History


November 2023: DOGAMI issues the Notice to Proceed (NTP) with the permitting process.

October 2023: The Technical Review Team (TRT) determines that the Consolidated Permit Application (CPA) is complete. Calico also files a clean copy of the CPA incorporating all changes previously submitted and noticed.

February 2023: The final baseline data report was accepted as complete by the TRT.

December 2021: Calico files a revised CPA.

February 2020: DOGAMI informs Calico that the CPA is not complete. 

November 2019: Calico files a CPA.

May 2017: Calico files a new notice of readiness to collect baseline data to accompany the February 2017 Notice of Intent (NOI).

February 2017: Calico files a new NOI, which replaces the July 2015 NOI. The new NOI expands the proposed permit boundary to 1,762 acres.

July 2016: Calico Resources is acquired by Paramount Gold Nevada Corp.

January 2016: Most of the baseline data collection was complete and approved by the TRT.

August 2015: Calico files a new notice of readiness to collect baseline data to accompany the July 2015 NOI

July 2015: Calico files a new NOI, which replaces the June 2012 NOI. The new NOI changes the proposed location of processing facilities and eliminates a haul road.

March 2013: Final baseline study collection plans are approved by the project TRT.

September 2012: Calico files a notice of readiness to collect baseline data.

June 2012: Calico files a NOI to develop a gold extraction and processing mine in Malheur County.

(last updated 11/21/2023)