Geological Setting, Deposit Types and Mineralization.
The coal deposits in the eastern USA are the oldest and most extensively developed coal deposits in the country. The coal-bearing formations on the properties are Carboniferous in age, being in the Pennsylvanian system, which includes the Monongahela, Conemaugh, Alleghany, and Upper Pottsville groups. These coal-bearing formations contain two-fifths of the nation’s bituminous coal deposits, extend over 900 miles from northern Alabama to Pennsylvania, and are part of what is known as the Appalachian Basin. The Appalachian Basin is more than 250 miles wide and in some portions, contains over 60 coal seams of varying economic significance. Seams are typically between 1 foot and 6 feet in thickness, with relatively little structural deformation. Coal in the region is classified as high- to low-volatile bituminous with rank increasing to the east. Coals are typically characterized as low to medium sulfur and high heat content.

Mineralization.
Mineable coal seams within the properties are typically low-ash, low to high-sulfur, and high- thermal content bituminous coals. Regionally, the coals are typically low-volatile in rank, with rank increasing from west to east. The maximum seam thickness may reach over 6.0 feet where multiple coal benches occur in proximity to one another; however, the average mineable thickness of the seams in this evaluation generally ranges from 1 foot to 4 feet. Seams are generally continuous, but may be locally absent. Secondary discontinuity due to erosional features is present in most areas, resulting in seam outcropping, or visible exposure of the seam at the surface. Other than oxidation of the coal exposed at the surface, erosion of the seams has no significant impact on the mineralized deposits. Mineable seams associated with the properties are generally outcrop-accessible. Coal seams are characterized by both single-bench and multiple-bench coal horizons with parting (non-coal) material varying by seam and area. Seam parting is common within the coal seams on the properties with intra-seam parting material increasing drastically in some areas. Roof strata are typically shale or sandy shale with zones of sandstone roof being common. Floor strata are typically sandstone, shale, sandy shale, fireclay, or in the case of the Upper Kittanning, limestone.

Coal Seams of Interest.
Surface-mineable Seams: There are seven primary coal seams (and associated splits) identified on the properties exhibiting surface-mineable potential. Surface-mineable coal seams are contained within the upper and middle portions of the stratigraphic section and include coal seams from the Sewickley through the Lower Kittanning coal seam. There are 11 areas within the properties where coal seams exhibit surface-mineable potential including: Bassett, Berwind Lohr, Bluelick 4, Byers, GAZ, Downey, Hart, Rhoads II, Schrock Run/Schrock Run Extension, Hamer and Shaffer. Hamer and Byers are directly adjacent to each other and are therefore reported together herein as Hamer-Byers.

Underground-mineable Seams: There are six coal seams identified on the properties exhibiting underground-mineable potential. These coal seams are contained within the middle to lower portions of the stratigraphic section and include the Upper Freeport (E), Lower Freeport (D), Upper Kittanning (C’), Middle Kittanning (C), Lower Kittanning (B), and Brookville (A) coal seams.

Keyser – Middle Kittanning Seam.
The Keyser property includes a Middle Kittanning seam is an inactive underground deposit that could potentially produce a metallurgical-grade coal. The property is controlled largely through ownership and is not permitted. The resource area occurs entirely within the owned property. The seam is relatively thin, in comparison to other Corsa underground mineable coals, with an average thickness of 2.9 feet. The available analytical data is insufficient to characterize the quality of the seam. The mineable Lower Kittanning seam also occurs within the Keyser property boundary at an interval of 53 feet below the Middle Kittanning. The Middle Kittanning seam at Keyser has been identified as a resource, while the Lower Kittanning has been evaluated as a reserve.

Keyser – Lower Kittanning Seam.
Keyser is an inactive underground property with the potential to produce metallurgicalgrade coal. The property is controlled largely through ownership and is not permitted but in the permit process. The reserve area occurs entirely within the owned property. The Lower Kittanning seam has an average thickness of 4.4 feet and underlies the Middle Kittanning seam at an interval of 53 feet. The water pool elevation in the overmined Upper Kittanning seam acts as a mine barrier to northward expansion of the Lower Kittanning resource area. A hydraulic barrier to the south prohibits the mineable resource from extending beyond the 1,750 feet seam elevation which is the bottom of the box cut elevation. These two barriers have reduced the area of mineable coal as originally projected by Wilson Creek Energy.

Underground mine reserves are mined using continuous mining room and pillar methods.

There are currently three active underground mines operated by Corsa: Acosta, Horning and Casselman. The Keyser underground mine is expected to begin production in 2023.

The projected mines are assumed to operate similarly to the active mines, using the same equipment, crews, and methodology. Each mine is scheduled to operate one or two production sections, each configured as a single continuous miner section, most using continuous haulage.

All of the mines can be accessed by box cut openings or highwall exposed by surface mining operations. Pillar extraction is not assumed for any of the current or future operations since no such plan has been approved by the appropriate regulatory agencies for those operations.
[2019, AIF, p.45]

Mine: Keyser LK.
The Lower Kittanning seam is accessed via a proposed box cut. This mine is projected to be a metallurgical coal operation on owned mineral property.

Production is scheduled for 255 days each year, which represents production on Monday through Friday. On each day, two production sections are scheduled to produce coal on two shifts; the third shift is reserved for maintenance and mine conveyor belt and power moves. The sections are configured as regular sections with one continuous miner each available for production. Productivity is planned at the rate of 180 feet of advance per shift of operation.

Principal production equipment includes two continuous miners, four roof bolters, six shuttle cars, and two scoops. Coal is extracted from the production face with the continuous miner and hauled to the mine conveyor in shuttle cars. At the conveyor belt, the coal is discharged from the shuttle cars onto a feeder breaker for transfer onto the conveyor. The conveyors carry the coal to the outside, where it is stacked on the ground to await truck transport to the preparation plant and load-out.

Expected annual production averages approximately 514,000 marketable tons at steady state levels.

Recovery Methods.
Materials Handling and Coal Preparation.
Raw coal produced from the mine is currently delivered by truck to the Cambria and Shade coal preparation facilities. In addition to the Cambria and Shade plants, Corsa has the Rockwood plant on care-and-maintenance status which can be reactivated in the future when production level exceeds the capacity at the Cambria and Shade plants.

Some raw coal produced from the mine is shipped directly to the customer on a raw basis or blended with processed or purchased coal, depending on coal quality and specific customer requirements. Corsa preparation facilities have raw coal handling systems consisting of a rotary breaker and screen used to remove large rock and size raw coal. Raw coal is then shipping on a raw basis or blended with washed coals from the preparation plant.


Raw coal to be processed is stockpiled, then loaded by a wheel-loader into a hopper for conveyor transport into the coal prep ........