Integra Resources’ Florida Canyon gold mine in Nevada processes ore through a conventional crush, agglomerate, and heap leach flowsheet. With over 40 years of history, the operation is now focusing on a series of optimization projects to enhance recovery and throughput.
The Florida Canyon Gold Mine is a producing open-pit heap leach gold mine wholly owned by Integra Resources Corp., located in Pershing County, Nevada, USA. The operation is situated adjacent to Interstate Highway I-80, approximately 125 miles northeast of Reno. Ores from several deposits, including Main, Central, Jasperoid, North pit, and Radio Towers, are processed through conventional cyanide heap leaching, adsorption, desorption, and regeneration technology to produce a final doré product. With a history of production since 1986, the operation is now evaluating a range of process optimization projects to enhance gold recovery and throughput.
Critical Data
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Crushing circuit target throughput | 21,000 | tons per day | Current design target |
| Final crush size (P80) | 2.5 | inches | Two-stage open circuit |
| Barren solution application rate | 0.003 | gpm/ft² | Average via drip irrigation |
| Total barren solution flow rate | 10,400 | gpm | Recycled to pad |
| Average total carbon column flow | 9,900 | gpm | Across three CIC trains |
| Primary leach cycle | 101 | days | Based on 40-foot lift at 1,200,000 tons per month |
| Carbon elution vessel | 3 | tons | Modified Zadra system |
| Elution solution temperature | 260 | °F | Thermal fluid heater |
| Electrowinning cells | 2 | cells | In series, 750 Amp each |
| Reactivation kiln capacity | 550 | lb/hr | Only about 25% of carbon thermally reactivated |
| Refining furnace | 150 | kW | Induction furnace |
| Total pond volume (existing) | 53.3 | million gallons | 4 ponds, 3-foot freeboard |
| Cyanide consumption (2025) | 0.40 | lb/ton | Sodium cyanide |
| Lime consumption (2025) | 2.20 | lb/ton | Pebble lime |
| Estimated electrical power demand | 990,000 | kWh/month | Processing facilities |
| Estimated water requirements | 100,000 | tons/month | Makeup water |
| Cumulative gold recovery (SHLP start-up) | 58.7 | % | From Jan 2017 through end of 2025 |
| Gold recovered (SHLP start-up) | 476,665 | oz | Jan 2017 to end of 2025 |
| Average CIC gold recovery | 82.6 | % | Referenced period |
| Average CIC silver recovery | 44.1 | % | Referenced period |
| Maximum crusher throughput (permit) | 10 | million tons per annum | Permit restriction |
| Maximum ore to leach pad (permit) | 18 | million tons per annum | Permit restriction |
Overview
The recovery process at Florida Canyon begins with ore that is either crushed or placed as run-of-mine (ROM) material. Traditionally, ore placed on the leach pads was crushed, but FCM began processing ROM ore in 2022 to increase gold production. Crushed ore passes through two stages of open circuit crushing to achieve a final crush size of 80% minus 2.5 inches. This crushed material is then agglomerated with a polymer binding agent to improve solution percolation through the leach pad. It is delivered to the South Heap Leach Pad (SHLP) via haul truck, or alternatively through mobile ramp conveyors and grasshopper conveyors. The overland conveyor system is currently not being utilized due to operational issues, with potential re-implementation under study. Crushed and ROM ores are co-mingled at the pad dump face, and lime is added to control pH.
The leaching process uses a dilute cyanide solution applied through drip irrigation. Pregnant solution from the bottom of the pad reports to a pond and is pumped to three trains of carbon columns, where precious metals adsorb onto activated carbon. Barren solution from the carbon circuit is screened, re-dosed with cyanide to a target concentration of 250 ppm, and recycled to the pad. Loaded carbon is transported to the ADR plant for elution, followed by electrowinning and smelting to produce doré bars. The final product is shipped to a third-party refiner at roughly 50% gold and 45% silver purity, with copper as the major impurity.
Key Process Stages
The ore stacking stage begins with preparation of the pad surface. Prior to placing a new lift, the area is deep ripped by a track dozer to break up the crust and remove solution channels. After placement, new ore is ripped and crossed ripped twice, with the final rip to a depth of 6 feet before the drip tubing is placed. The tubing is typically placed directly on the ore surface.
Barren solution is applied selectively to different areas of the pad through drip tubing at an average rate of 0.003 gpm/ft². With a total barren solution flow rate of 10,400 gpm, approximately 2.6 million ft² of heap area can be leached. At an ore production rate of 1,200,000 tons per month, split evenly between crushed ore and ROM, placed on a 40-foot lift, the primary leach cycle is 101 days. Secondary leaching continues as solution percolates through subsequent ore lifts.
Pregnant solution from the bottom of the pad reports to the pregnant solution pond and is pumped to three trains of carbon columns. Each train operates as a 5-stage counter current arrangement. The E1 column train can process 3,100 gpm, the E2 train processes 1,800 gpm, and the E3 train processes 5,000 gpm. The average total flow rate to the carbon columns is 9,900 gpm. There is no intermediate or recycled pregnant solution back to the leach pad. Carbon column discharge is screened at 120 mesh to remove carbon fines and reports to the barren pond or pump box.
Loaded carbon is transported by truck to the elution plant, where gold is stripped using a modified Zadra system with a single 3-ton strip vessel. The desorbed gold and silver is recovered electrolytically by two electrowinning cells in series. The stripping solution is adjusted to pH 13 with sodium hydroxide and heated to 260 °F by a thermal fluid heater combined with a series of heat exchangers. Solution flow rate through the vessel is 60 gpm. The stripped carbon is screened to remove fine carbon, thermally reactivated as required, and then acid washed in hydrochloric acid to remove carbonate scale. The volume of carbon being stripped exceeds the capacity of the reactivation kiln, so only about 25% of the carbon is thermally reactivated.
The plated material from electrowinning is retorted prior to refining to remove mercury and to dry it. Once retorted, the sludge is mixed with flux and smelted in a 150 kW induction furnace. Doré bars are the final product at FCM and are shipped to a third-party refiner.
Additional Interesting Data and Summary
The SHLP expansion was completed as leach pad Phases 1 and 2 approached the 300-foot stack height limit above liner. The expansion included Phase 3A, completed in Q1-2025, and Phase 3B, completed in Q1-2026. A subsequent expansion is now underway. Additional CIC circuit and solution pumping capacity were commissioned in Q3-2024, doubling system flow to 10,400 gpm. The third carbon column train, rated at 5,200 gpm, was installed adjacent to the existing columns. Residual leaching of Phases 1 and 2 is expected to continue for two to three years after stacking is complete.
Since start-up in January 2017, 476,665 ounces of gold have been recovered from the SHLP through the end of 2025. Cumulative gold recovery during this time is 58.7%. This recovery, from a mixture of crushed and ROM ores, was achieved with an overall solution to ore ratio of 1.0 and leach cycles ranging from 90 to 120 days. Overall contained ore grade for this period was 0.0092 oz/ton.
The primary reagents used at FCM are sodium cyanide, pebble lime, activated coconut shell carbon, agglomeration polymer, and hydrochloric acid. In the previous five years, from 2020 to 2025, the average consumption rates for cyanide and lime were 0.31 lb/ton and 2.35 lb/ton, respectively. FCM ores contain minor amounts of mercury that dissolve in cyanide solution and adsorb onto activated carbon. All thermal units are operated with their own mercury abatement system, capturing mercury emissions in the exhaust air through beds containing sulfur-impregnated activated carbon.
Several optimization projects are currently being evaluated. One option involves replacing the existing crushing circuit with a new system, with an estimated cost of $28.5 million for a similar capacity of 10 million tons per year at a P80 of 1.5 inches. Another approach involves installing a separate cone crusher and screen to achieve a modified P80 of 1.5 inches, with an estimated capital cost of $8.7 million. Crushing all material with only a jaw crusher would yield a P80 of roughly 3.5 inches, anticipated to achieve 60% gold extraction. Pad segregation of ROM and crushed material is being investigated due to the potential for fines migration and dry areas in the leach. The addition of a new CIC column to the E3 train is also under study, which should improve gold and silver recovery to carbon. Historic waste dumps containing 42.3 million tons at an average grade of 0.007 oz/ton gold are being investigated for retreatment using a scalping grizzly concept.
Key Processes
- Two-stage open circuit crushing to P80 of 2.5 inches, with a current target of 21,000 tons per day.
- Agglomeration of crushed ore with a polymer binding agent to improve solution percolation.
- Co-mingling of crushed and ROM ores at the pad dump face, with lime added separately for pH control.
- Drip irrigation application of barren solution at an average rate of 0.003 gpm/ft².
- Three 5-stage counter current carbon-in-column trains for precious metal adsorption.
- Modified Zadra elution system with a single 3-ton strip vessel.
- Two electrowinning cells in series for gold and silver recovery.
- Mercury abatement systems on all thermal units using sulfur-impregnated activated carbon.
- Retorting, smelting in a 150 kW induction furnace, and shipment of doré bars to a third-party refiner.
Source: NI 43-101 Technical Report, Florida Canyon Gold Mine, July 28, 2026. Project website: Florida Canyon Gold Mine
Technical report and processing history
The following archived source profiles have been consolidated here to preserve the project’s processing history and study context.
Florida Canyon Gold Mine — 2024 Technical Report
Florida Canyon Gold Mine — 2024 Technical Report
| Company | Florida Canyon Gold Inc. |
| Mine | Florida Canyon Gold Mine |
| Date | 2024-07-11 |
| Region | Nevada, USA |
| Commodities | Gold, Silver |
| Status | Operating |
Executive Summary
This NI 43-101 Technical Report outlines the operational status and processing infrastructure for the Florida Canyon Gold Mine (FCM). The mine has operated for over 35 years as a heap leach operation, utilizing conventional heap leaching, adsorption, desorption, and regeneration (ADR) technology to produce doré bars. Current infrastructure is in place to sustain production, with ongoing expansions planned for the South Heap Leach Pad (SHLP) and Carbon-in-Column (CIC) capacity to double flow rates by Q3 2024.
The processing circuit involves two-stage open circuit crushing to 80% minus 1.5 inches, followed by agglomeration with a polymer binding agent. Ore is stacked on pads and leached with cyanide solution applied via drip irrigation. Pregnant solution is processed through carbon columns for precious metal adsorption, followed by elution, electrowinning, and smelting. The operation manages mercury emissions through abatement systems and produces doré bars at 90-95% Au/Ag purity for third-party refining.
Website: https://integraresources.com/asset/florida-canyon-mine/
Report Date: 2024-07-11
Region: Nevada, USA
Project Status: Operating
Commodity: Gold, Silver
Throughput:
Mine Life:
Mine Type:
Ore type:
Florida Canyon Mine: Heap Leach Gold Recovery at a Four-Decade Nevada Operation
The Florida Canyon Gold Mine is a producing open-pit heap leach gold mine wholly owned by Integra Resources Corp. The mine is located in Pershing County, Nevada, approximately 125 miles northeast of Reno near Interstate 80. The operation has been in production since 1986 and as of March 31, 2026, had produced approximately 2.7 million ounces of recovered gold. The site processes ore from the Main, Central, Jasperoid, North, and Radio Tower pits through conventional cyanide heap leaching with carbon-in-column (CIC) and ADR technology to produce doré bars.
Critical Data
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Crushing circuit target throughput | 21,000 | tpd | Target for two-stage open circuit |
| Crush size (P80) | 2.5 | inches | Final product specification |
| Primary leach cycle duration | 101 | days | At 1,200,000 tons/month on 40-ft lift |
| Average barren solution application rate | 0.003 | gpm/ft² | Drip irrigation |
| Total barren solution flow rate | 10,400 | gpm | After 2024 expansion |
| Total flow to carbon circuit | 9,900-10,400 | gpm | Three CIC trains |
| Cumulative gold recovered from SHLP (Jan 2017-Dec 2025) | 476,665 | oz | From start-up through end of 2025 |
| SHLP cumulative gold recovery | 58.7 | % | From Jan 2017 through Dec 2025 |
| Overall contained ore grade (Jan 2017-Apr 2026) | 0.0092 | oz/ton | From SHLP production data |
| Solution-to-ore ratio | 1.0 | Overall average | |
| Leach cycles range | 90-120 | days | Historical operating range |
| Sodium cyanide consumption (2025) | 5,820,445 | lb | Annual total |
| Lime consumption (2025) | 32,081,690 | lb | Annual total |
| Total pond volume (existing) | 53.3 | million gallons | 4 ponds, 3-ft freeboard |
| Estimated processing electrical demand | 990,000 | kWh/month | For processing facilities |
| Estimated water requirement | 100,000 | tons/month | From geothermal wells on property |
| Carbon kiln capacity | 550 | lb/hr | Existing |
| Refining furnace capacity | 150 | kW | Induction furnace |
| Maximum crusher throughput under current permits | 10 | million tons/year | Permit restriction |
| Maximum ore to leach pad under current permits | 18 | million tons/year | Permit restriction |
Overview
The Florida Canyon Mine recovery process follows a conventional heap leach flowsheet. Ore from multiple open pits is crushed through two stages of open circuit crushing to a P80 of 2.5 inches. Crushed ore is agglomerated with a polymer binding agent and delivered to the South Heap Leach Pad (SHLP). Since 2022, run-of-mine (ROM) ore has been processed alongside crushed material to increase gold production. Crushed and ROM ores are co-mingled at the pad dump face. Lime is added for pH control.
Barren cyanide solution is applied through drip irrigation. Pregnant solution reports to the pregnant solution pond and is pumped to three CIC trains where gold and silver adsorb onto activated carbon. Loaded carbon is processed in a 3-ton Zadra elution vessel. Gold and silver are recovered by electrowinning, retorted to remove mercury, and smelted in a 150 kW induction furnace to produce doré bars. The bars contain approximately 50% gold and 45% silver with copper as the major impurity.
The SHLP expansion included Phase 3A completed in Q1-2025 and Phase 3B completed in Q1-2026. Additional CIC circuit and solution pumping capacity were commissioned in Q3-2024, doubling system flow to 10,400 gpm. A third carbon column train rated at 5,200 gpm was installed.
Key Process Stages
Ore preparation begins with two stages of open circuit crushing. The current system operates at a target of 21,000 tons per day. After crushing, material is agglomerated with a polymer binding agent. For stacking, the area beneath a new lift is deep ripped by a track dozer to break up crust and remove solution channels. New ore is ripped and crossed ripped twice with a final rip to 6 feet depth before drip tubing placement.
Barren solution at approximately 250 ppm cyanide is applied through drip tubing at 0.003 gpm/ft². At 10,400 gpm total flow and an ore production rate of 1,200,000 tons per month on 40-foot lifts, the primary leach cycle lasts 101 days. Secondary leaching continues as solution percolates through subsequent lifts.
Pregnant solution reports to three CIC trains in a 5-stage counter-current arrangement. The E1 train processes 3,100 gpm, the E2 train processes 1,800 gpm, and the E3 train processes 5,000 gpm. There is no recycled pregnant solution to the leach pad. Barren solution is screened at 120 mesh and re-dosed with cyanide before recycling at approximately 10,000 gpm.
In the elution plant, loaded carbon is stripped in a 3-ton Zadra vessel under elevated temperature and pressure. Stripping solution is adjusted to pH 13 with sodium hydroxide and heated to 260°F. Flow through the vessel is 60 gpm. Two electrowinning cells in series recover gold and silver from solution. Stripped carbon is screened, thermally reactivated as required, and acid washed in hydrochloric acid. Only about 25% of the carbon is thermally reactivated due to kiln capacity limitations.
Mercury abatement systems capture mercury emissions from the kiln, smelting furnace, retorts, electrowinning cells, and associated tankage using sulfur-impregnated activated carbon beds.
Additional Interesting Data and Summary
The SHLP has operated since January 2017. Through April 2026, the pad processed 97,519,679 tons of ore containing 830,417 ounces of gold at an average grade of 0.009 oz/ton. Cumulative gold recovery over this period was 58.9%, totaling 489,299 ounces. Historical performance since the SHLP start-up shows 476,665 ounces recovered through end of 2025 with 58.7% cumulative recovery from mixed crushed and ROM ores. Leach cycles ran from 90 to 120 days with an overall solution-to-ore ratio of 1.0.
A series of optimization projects are under evaluation at FCM. These include expanding crusher capacity, optimizing crush size to improve extraction, treating all material with primary crushing only, segregating ROM and crushed ore on the pad, improving thermal reactivation with a new kiln, adding CIC capacity, and retreating waste dumps by scalping finer material.
The existing crusher can process about 8 million tons per year at P80 of 2.5 inches. Analysis indicates a finer size distribution to P80 of 1.5 inches could be achievable by installing a separate cone crusher and screen. The estimated capital cost for this option is $8.7 million with $0.75 per ton additional operating cost. Improving recovery from 68% to 76% with this change would yield an estimated 6,800 additional ounces of gold per year.
Crushing all material with only a jaw crusher to P80 of approximately 3.5 inches would yield an estimated 60% gold extraction. The current jaw crusher can treat about 10 million tons per annum. Minor conveyor modifications at $2 million would be required. Operating cost would decrease to $1.00 per ton. Two subcases were examined: maximizing high-grade primary crushing to 10 mtpa without crushing low-grade ROM, and adding a second primary crusher for low-grade ROM. Case 1 yields an estimated 5,600 ounces per year incremental increase. Case 2 yields 9,100 ounces per year.
For ADR improvements, a new carbon regeneration kiln with 750 kg/hour capacity carries an estimated cost of $2.8 million. Adding a new CIC column to the E3 train is estimated at $5.4 million. Average CIC recovery for gold was 82.6% and for silver was 44.1%. Adding a column should improve recovery toward typical targets of +95%.
Historical waste dumps containing 42.3 million tons at an average grade of 0.007 oz/ton gold are being investigated for retreatment. The material has a coarse particle size of P80 approximately 7 inches. The overall value does not support crushing but low-cost size segregation using a scalping grizzly is under investigation.
Current permit restrictions limit crusher throughput to 10 million tons per annum and ore to the leach pad to 18 million tons per annum. Permit amendments are possible but require significant time.
Note: The source reports a "maximum crusher throughput – 10 million tons per annum" as a permit restriction, but Section 17.2 states the crushing circuit target as 21,000 tons per day (approximately 7.7 million tons per year at 365 days). The relationship between these values and the engineering studies for capacity expansion should be clarified by a human reviewer.
Key Processes
- Two-stage open circuit crushing to P80 of 2.5 inches at a target of 21,000 tpd
- Agglomeration with polymer binding agent
- Deep ripping of pad surface to 6-foot depth before drip tubing placement
- Barren solution application at 0.003 gpm/ft² through drip irrigation with 250 ppm cyanide
- Three 5-stage counter-current CIC trains: E1 at 3,100 gpm, E2 at 1,800 gpm, E3 at 5,000 gpm
- 3-ton Zadra elution vessel at 260°F and pH 13 with 60 gpm flow
- Two electrowinning cells in series
- Retorting for mercury removal
- 150 kW induction furnace smelting to doré bars at approximately 50% Au and 45% Ag
- Mercury abatement using sulfur-impregnated activated carbon beds on all thermal units
- Carbon thermal reactivation in 550 lb/hr kiln with acid washing
Source: NI 43-101 Technical Report Florida Canyon Gold Mine, 31 May 2026. Project website: Florida Canyon Gold Mine
Florida Canyon — Technical Report
Florida Canyon — Technical Report
| Company | FCMI |
| Region | Nevada, USA |
| Commodities | Gold, Silver |
| Mine Type | Heap Leach |
| Status | Operating |
Executive Summary
The Florida Canyon project is a conventional gold and silver heap leach operation located in Nevada. The process involves two stages of open circuit crushing to achieve a final product size of 80% minus 1.5 inches. The crushed ore is agglomerated with a polymer binding agent and stacked in 20-foot lifts on leach pads. Solution is applied via drip tubes at a rate of 0.0028 gpm/ft², with discharge sent to carbon columns for gold recovery, replacing the original Merrill Crowe process. The site is well-managed with excellent agglomeration and pad conditions, though the carbon circuit requires attention regarding reactivation capacity and pre-attritioning.
Water management is a critical component of the operation, governed by strict Nevada regulations requiring containment of 25-year storm events. The current pond system includes multiple barren, pregnant, and contingency ponds at both North and South Heap Leach Pads, along with a geothermal cooling pond. While previous concerns regarding pond overtopping have been rectified through improved solution management and dedicated evaporation ponds, ongoing water balance modeling is required to establish maximum operating levels and confirm pond volumes against current industry practices.
Future development potential exists for the sulfide mineralization located below the current oxide operation. While sulfide heap leaching is rare, assay samples show dissolution in cyanide. However, processing costs and recovery rates are currently unknown due to the acid-generating nature of pyrrhotite. Flotation testing is recommended to evaluate capital and operating costs for a sulfide circuit, and toll autoclave processing by Newmont is being considered. The site visit confirmed high efficiency in plant and crusher operations despite recent staff changes.
Reports
- reports/Florida_Canyon_Technical_Report
References
- Section 17.0 Recovery Methods
Website: https://integraresources.com/asset/florida-canyon-mine/
Report Date:
Region: Nevada, USA
Project Status: Operating
Commodity: Gold, Silver
Throughput:
Mine Life:
Mine Type: Heap Leach
Ore type:
