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.

Schrock Run – Lower Freeport and Upper Kittanning Seams.
Schrock Run (and the associated Schrock Run Extension area) is located in Somerset County, Pennsylvania within portions of the USGS Stoystown and Berlin 7.5-Minute quadrangles. This property is immediately west of the Cambria Preparation Plant. The Lower Freeport seam has been previously surface and underground mined within the project boundary of this property. Lower Freeport reservestonnage will include some surface remining of existing underground mine workings. The Upper Kittanning seam reserves include auger tons. Based on information provided by Corsa, it has been estimated that approximately 55 percent of coal production from this property could potentially enter the metallurgical coal market, with the remainder going to the steam market.

The Schrock Run (including the associated Schrock Run Extension area) property is active. Surface mining rights are reported as controlled on this property, the mineral is controlled through lease and ownership and the reserves are permitted. Surface mining ratios are 26.6: 1 within the reserve area. The Wills Farm Property, which is adjacent to the west of Schrock Run Extension, has been dropped since the 2014 TR. Seams previously considered as resource on Wills Farm included the Middle and Lower Kittanning.

Schrock Run (including the associated Schrock Run Extension area) are currently the only active surface mining operations at Corsa.

Eight surface-mineable resource areas were modeled and tested economically. Mining operations are projected to utilize area mining methods. The active Schrock Run operations will employ equipment capable of a combined production rate of 1,228 bcy/hr between two shovel spreads working two, 10-hour production shifts, 5 days per week. Staffing is sufficient to float vacation during the year. After depletion of the Schrock Run reserves the model assumes that one shovel spread is retired and the other spread is moved to subsequent reserve areas at a lower production rate of 540 bcy/hr, working one 10-hour production shift, 5 days per week. A total of 9 to 33 employees are assumed for the surface mines. Auger operations are assumed to be conducted by a contractor.

It is assumed that most of the spoil movement goes through a shovel bucket and is eventually returned to the pit for final reclamation. The dozer’s primary responsibility is cutting the initial benches for the drill and shaping the reclaimed contour highwall.

Spoil for final highwall reclamation is expected to come from strategic placement of spoil on preexisting benches by haul trucks such that they are within the push distance of the reclamation dozer. Surface mine recovery is assumed to be 90% from solid coal.

Coals from the surface operations are hauled to the preparation plant. Saleable product from the surface operations are projected to be sold into both the metallurgical and thermal coal markets. Roughly 50% of the proposed production planned for the thermal market is assumed to be washed, while the remainder of the thermal coal product is assumed to be shipped raw to customers.

Schrock Run (including the associated Schrock Run Extension area) is an active surface mining area scheduled to be completed in 2022. Expected production for the operations totals approximately 611,000 marketable tons.

Schrock Run auger operates in 2020 to 2022 and mines an additional 93,000 marketable tons.

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 ........