Deposit Types
At Chandalar, both lode and placer gold exist within the district. The placer deposit is the focus of this report, but a significant exploration potential exists to find and develop the lode deposits that were the source of the placer deposit.

Lode Deposits
Lode gold occurs throughout the Chandalar property in definable systems of veins, veinlets, disseminations, and auriferous lenses of quartz within or adjacent to northwest-trending shear zones.

The schist-hosted Mikado mineralization occurs in discontinuous elongate lenses and veins that pinch and swell as border zones of stockwork and sheeted veinlets. The Mikado shear zone, generally found in the hanging wall, contains the majority of the mineralization. Recurrent movement along the shear explains the discontinuous nature of the mineralization, the pulverization of quartz to a clayey sugary texture, and the numerous ragged inclusions of host rock.

Elsewhere, veins such as the Little Squaw, Crystal, Kiska, Prospector, and Grubstake are hosted in splay faults and are more competent and continuous and mineralization primarily occurs as pods and ore shoots. Overall, auriferous and subparallel quartz veins of the Chandalar district occur across a five-mile width and a northwest-trending four-mile strike length.

Placer Deposits
Placer gold in the Chandalar Mining district was liberated from lode sources of the former highland weathering surface that rose more than 3,000 feet (914 meters) above the surrounding lowlands during several episodes of erosion and concentration and was further complicated by repeated advances of Quaternary glaciation from the north. Subsequent downcutting on each glacial retreat occurred in response to newly established base levels along the wide valleys to the north and west of the district. These glacial events scoured the upper placer streams of Tobin, Boulder, Woodchuck, McLellan, and Big Squaw Creeks but did not destroy pre-glacial pay streaks at the lower valleys of Little Squaw, Tobin (above Woodchuck Creek), and probably not Big Squaw and McLellan Creeks. These pre-glacial placer deposits were preserved during glaciation, and significant targets remain.

The complex glacial-fluvial history of the Chandalar region formed placers and placer exploration targets that exhibit several differing deposit types. On the north and east side of the district, the placers are a combination of stacked sequences of normal fluvial and glaciofluvial channel deposit that have formed in second order streams and feature bedrock and false bedrock pay channels. On Little Squaw Creek, and possibly on Big Squaw and Nugget Creeks, resistant bedrock along the north margin of the hills has influenced rapid stream gradient changes that created ancestral canyons below which paleo-fluvial and modern glaciofluvial fans have formed.

The later type is formed by combined fluvial and glaciofluvial processes and is deposited on glacial falsebedrock. These processes result in deposition of significant thickness of auriferous sediment as exhibited at Little Squaw Creek and possibly within other drainages along the north side of thedistrict.

This deposit is geologically characterized as an aggradational placer gold deposit. The plan view of the Chandalar Mine deposit is somewhat funnel-shaped, and because of this has beendivided into two distinct geomorphological zones: the Gulch, or narrower channel portion, and the Fan, or broad alluvial apron portion.

Mineralization
Lode Mineralization
Most high-grade mineralized zones within vein systems are less than 150 feet long and 2 to 10 feet wide. Vertical extents are unknown but probably exceed 200 feet. Individual prospects discovered at various points along major shear zones were originally thought to be discrete discoveries, but groups of prospects have since been determined to be related along a common structure.

Placer Mineralization
Placer gold occurs within the pre-glacial fluvial, interglacial glaciofluvial, and post-glacial fluvial, permafrost deposits on Little Squaw Creek. The gold is coarse, crystalline, and bright, indicating that it was transported only a short distance from its sources. Small nuggets are common, and there is little finegrained gold (-80 mesh). Quartz inclusions and attachments are common on gold particles but make up only a few percent by volume.

The pay streak on Little Squaw Creek is subdivided into the “canyon” placer upstream of a bedrock constriction underlying Lines 4.8 through 6, and an “alluvial fan” placer downstream of the buried constriction that extends at least as far north as Line 1.2., a distance of about 2,000 feet. Fluvial gravel hosting the placer is mostly composed of gray to black chloritic schist, which is commonly seen in the surrounding hills. Gold-bearing gravels composing the alluvial fan range from 15 to 137 feet thick and average 80 feet thick over a width of up to 1,262 feet. The pay streak within the fluvial gravel on the canyon section varies from 50 to 136 feet thick over a width from 240 to 570 feet. The placer deposit is open to further mineralization to the east, west, and north.

Overburden on the fan is composed of frozen, clay-rich glacial till. Ice is moderately abundant in the overburden of the alluvial fan and may compose 10% of the total volume. Ice is particularly prevalent under the western end of Line 1.2, where it forms massive lenses 15 to 20 feet thick in Hole 18. Thawing ice appears to be responsible for the actively subsiding thermokarst pond east of the road. The barren till overburden averages 65 feet thick. Overburden on the canyon placer is mixed glaciofluvial sediments and can carry minor concentrations of gold at the surface and disseminated throughout. The overlying barren sections have a highly variable thickness, ranging from 0 to 75 feet with a 41-foot average.

Conventional open pit mining methods using drill, blast, load, and haul mining are applicable to the Chandalar Mine because the gravel is frozen (permafrost).

The pit shell was segregated into six separate pits or pit pushbacks designated as Lower Pit A, Lower Pit B, Lower Pit C, Upper Pit A, Upper Pit B, and Upper Pit C. Each pit was designed with haul roads.

A preliminary mining schedule was generated from the base case pit resource estimate:

• Process Material Production Rate: 4,000 bcy per day (ypd) for the first year (with one wash plant) and 8,000 bcy per day for subsequent years (with two wash plants)
• Mine Operating Days per Week: 7
• Mine Operating Period per Year: All of first three quarters (January 1 through October 31), with processing of mined material occurring only between May 17 and September 13 (120 days).
• Mine Operating Shifts per Day: 2
• Mine Operating Hours per Shift: 12

Additional design work and phasing of the pits/pushbacks will likely better balance the annual process and waste stripping and metal production. Likewise, adding more blasting and waste stripping days to the seasonal schedule will help smooth out the production schedule.

High-grade material stockpiled during the first- and second-year ramp ups to full production and lowgrade stockpiled material was scheduled to be processed after completion of regularly scheduled highgrade material processing.

For scheduling, used a 20-foot bench height with a 68.2-degree batter angle for the Chandalar Mine pit designs. In practice, mining a shorter bench height may be preferable to increase selectivity. Catch benches would occur on every bench with a width of 12 feet. This results in overall inter-ramp pit slopes of 45 degrees.

Three waste rock dumps (WRDs) are planned at different locations around the pits. The WRDs are designed to contain total of 8.1 million loose cubic yards of waste material. The sides of the WRD are at a 2.5:1 slope, and the material would be end dumped. The remaining waste will be placed as concurrent backfills in mined out phases of the pits. Thirty-five (35) % of the waste material is concurrently backfilled in the mining pits. The backfilling of the previously mined out pits during the active mine life is planned to minimize the amount of waste material that needs to be reclaimed at the end of the mining operation. The backfills are designed at a slope of 3:1 (h:v) suitable for the reclamation plans for closure as per BLM and ACOE requirements. The pits would be backfilled from the bottom up to meet the reclamation plan. The backfill and WRDs are utilized concurrently through the mine life for waste produced from the pit. After mining has finished, the pits will be filled with the waste material from the WRDs.

Prior to 2013, the historical recovery methods at Chandalar Mine have used gravity systems consisting of a rotating trommel and sluice arrangement. A wash plant using the newer shaker deck system was used at Chandalar Mine for the 2013 through 2018 production seasons.

Process Plant Description
Dr. Harvey has extensive experience with placer recovery equipment and as a result has selected a stateof-the-art system for the Chandalar Mine project. Further, the rehandling of materials and haulage are two of the major expenses associated with placer mining, and a proper design can significantly reduce these costs. As a result of this, Dr. Harvey has recommended the use of two mobile wash plant shaker systems combined with a feed hopper with a side dumping grizzly, a belt feeder, and plant feed conveyor. The plant consists of a feed receiver with water sprays, a vibrating screen deck, and a double sluice box.

The coarse tailings are transported via a series of por ........