The targeted coal seams for Shoal Creek are typically mid to high volatile bituminous coals, which can be sold as metallurgical coal due to high fluidity and coking properties. The coal seams of interest, Mary Lee and Blue Creek, are of Pennsylvanian Age and are part of the Mary Lee Coal Group of the Pottsville Formation within the Warrior Coal Basin of the Southern Appalachia Coal Producing Region. The thickness of the Mary Lee and Blue Creek seams is heavily dependent upon the location of the ancient fluvial system that scoured the topography with valleys. Areas where the ancient fluvial system scoured deep valleys allowed for thick peat accumulation and therefore thicker coal deposits for the Mary Lee and Blue Creek seams. The major ancient fluvial valley trends northwest/southeast across the Shoal Creek property. High angle normal faults are common across the property and often display horst and graben structures. The general strike of the coal seams is northwest/southeast, with a dip of one degree to the southwest.

The Mary Lee and Blue Creek seams are mined as one mining section at Shoal Creek utilizing underground mining methods. The depth of cover over the Mary Lee and Blue Creek seams at Shoal Creek ranges from approximately 800 feet in the eastern area of the property, to 1,700 feet in the west.

The coal deposit type of the Shoal Creek mine is considered to have a medium geologic complexity based on the following factors:
• The Mary Lee and Blue Creek seams are laterally continuous and can be correlated across the property with the use of geophysical logs, interburden thicknesses and seam thicknesses;
• The seams are gently dipping with numerous undulations due to the existence of the ancient fluvial system. This has added variability to the seam thickness of the Blue Creek seam;
• There are multiple high angle normal faults across the property, However, the faults do not prohibit the correlation of the Mary Lee and Blue Creek seams;
• The Mary Lee and Blue Creek seams are currently mined throughout the property across several counties;
• The local quality variations found throughout the property are not extreme enough to prevent a saleable product once the coal has been cleaned at the Preparation Plant.

Northern Alabama lies within the southern portion of the Appalachian coal region and contains three primary coal fields in the northern half of the state. These are the Warrior, Cahaba, and Coosa. The Shoal Creek property lies within the east-central portion of the Warrior Coal Field. The Warrior Coal Field is within the Pennsylvanian aged Pottsville Formation and is divided into two separate regions: The Plateau Coal Basin, and the Warrior Coal Basin which contains the Shoal Creek property.

The Warrior Coal Basin lies within the Cumberland Plateau section of the Appalachian Highlands and is bound on the eastern side by the Opossum Valley thrust fault. The Mary Lee Group outcrops along the northern and eastern edges of the Warrior Coal Basin. The southern portion of the basin is bound by the East Gulf Coastal Plain sediments. The Warrior Coal Basin dips one to two degrees to the southwest and the coalbeds plunge into the basin dipping as much as nine degrees.

The overlying strata of the Pottsville Formation are Cretaceous (145-66 million years ago) and Tertiary (66-2.6 million years ago) deposits of the Mississippi Embayment and Gulf Coastal Plain. The depositional environment associated with the Pottsville Formation of the Warrior Basin is interpreted as a barrier/back barrier setting with lithologic sequences that indicate marine nonmarine nearshore sedimentation. The lithology of the Pottsville Formation includes; interbedded sandstone, siltstone, claystone, shale, and bituminous coal. The thickness of the Pottsville Formation varies, with some local measurements exceeding 8,000 feet. The depositional sequences that are found within the Pottsville Formations usually follow this succession: a ravinement surface that is overlain by an interval of marine fossil assemblages, a thick gray mudstone that ranges in thickness from 30 to 300 feet, which then coarsens into sandstone and conglomerate. The sandstone is then succeeded by a heterogeneous coal zone that consists of mudstone, sandstone, conglomerate, underclay, and coal.

The Shoal Creek Mine is located within the Warrior Coal Basin. The coalbed mined is the Mary Lee and Blue Creek seams that are part of the Mary Lee Member Coal Group of the Pottsville Formation, which formed during the Pennsylvania age.

The Sequatchie Anticline and the Warrior Syncline are the two most prominent features influencing the structural attitude of the strata within the Shoal Creek property. The Coalburg Syncline is located in the region to the southeast of the Shoal Creek property. Faults tend to cluster within the two synclines, with one of the highest concentrations of faults located near the axis of the Warrior Syncline. The majority of the faults trend from the southeast to the northwest. The faults nearest to, and just west of the Warrior Syncline tend to be high angle (60 degrees) normal faults, as much as four miles in length, and with offsets ranging from 10 feet to over 240 feet.

Regional and local lineaments are present throughout the Shoal Creek property. The regional lineaments are orientated northeast to southwest and east to west. Local lineaments are generally perpendicular to the regional lineaments but can also be parallel. The coal cleat direction at Shoal Creek is usually N 60 E and joint direction is usually N 90 E, which follow the regional lineaments and fold axis orientations.

Three major coal groups are intersected in the drilling within the Shoal Creek property; Cobb, Pratt, and Mary Lee. Each coal group contains consistent coal marker beds, these are the Cobb, Pratt, American, and New Castle. The overburden down to the Cobb seam within the Cobb Group has an average thickness of approximately 475 feet. The interburden between the Cobb seam within the Cobb Group and the American seam of the Pratt Group has an average thickness of approximately 325 feet. The interburden between the American Seam of the Pratt Group and the New Castle Seam of the Mary Lee Group has an average thickness of approximately 450 feet. The Mary Lee Group is comprised of five coal seams, which in descending order are the New Castle, Mary Lee, Blue Creek, Jagger, and Ream. The interburden between the New Castle Seam of the Mary Lee Group and the Mary Lee Seam of the Mary Lee Group has an average thickness of approximately 40 feet but can range between 20 and 55 feet.

The interburden between the coal seams is primarily shales and sandstones, with thin fireclays underlying the coal seams in many areas. The sandstones are dark gray containing mica, clay and carbonaceous material. They are well cemented, of medium hardness and very fine grained. They range in thickness from less than 10 feet to approximately 40 feet.

The coal to be mined is the Mary Lee and Blue Creek seams which are in the Pottsville Formation. The Mary Lee and Blue Creek seams typically occur at depths ranging between 800 to 1,700 feet. The Mary Lee seam has a fairly uniform thickness ranging between 1 feet and 1.5 feet throughout the mine plan area. The Blue Creek seam ranges from 2.5 feet to 6.0 feet thick. This thickness is largely determined by interburden thickness below the Newcastle seam. A greater interburden thickness correlates with an increase in coal thickness.

The mining method best suited for this underground mine is the longwall mining method which has a relatively high recovery rate. The mains and gate roads are required to be developed with the continuous miner prior to the longwall mining. Since the beginning of production at Shoal Creek, this method appears to be relatively safer and more efficient compared to other available methods. Both the Mary Lee and Blue Creek coal seams are economic when they can be extracted together. Due to the parting between the two seams and the out of seam dilution, the operation utilizes a washing plant to process the ROM coal to meet coal quality specifications. For this underground operation, the key consideration includes roof control, subsidence, ventilation, dewatering, mine planning and production schedules, etc.

Mine Design
The operation follows the approved Mine Safety and Health Administration (MSHA) roof control plan to address potential geotechnical issues encountered under current geological and mining conditions, such as mining depth, mining height, and entry widths, etc. The depth in the LOM plan area ranges from 1,000 to 1,300 feet. The typical roof controls are mainly described here for the development section (i.e., mains and gate roads) and the longwall mining system.

For mains development with a six to seven entry system, the typical pillar sizes are 90 feet by 150 feet (center-to-center). The typical entry and crosscut width are 20 feet.

The typical longwall gate roads developed by the continuous miner sections consist of three entries with widths typically 100 to 120 feet(center-to-center). Crosscut centers are typically 150 feet. The typical entries and crosscuts are 20 feet wide. The approved MSHA roof control plan allows maximum entry and crosscut widths of 22 feet at planned intersections. The entries may be mined up to 25 feet wide with the installation of additional permanent supports.

The roof control plan approved by MSHA includes the use of primary supports during mains and gate road development, as well as secondary supports at the longwall tailgate. The operation can use any type of roof bolts from the approved list. This includes the combination bolt, point anchor and tensioned rebar, full resin-grouted bolt, mechanically anchored tensioned bolt, and truss bolt for the primary roof support. Other supplemental roof support materials can be used as needed, such as timers, pumpable cribs, prop-setter, etc. When mining both Mary Lee and Blue Creek seams with a height exceeding eight feet, rib bolts with a minimum of six feet in length is required to be installed through the middleman (parting strata).

Ventilation Considerations
Methane is the main hazardous gas released during the mining process. The current mine planning area shows relatively low methane content from production due to historic Coal Bed Methane (CBM) production. The surface aerial image shows clearly a densely spaced pattern of sites for CBM wells on top of the projected mining area at Shoal Creek. The mine ventilates the underground mine works by utilizing fans installed on the surface in an exhaust system. The main ventilation facilities are listed in Table 13-1. Other underground ventilation controls used include stoppings, seals, tubes, curtains, regulators, auxiliary fans, etc. The operation follows the approved ventilation plan by MSHA to control hazardous gas and dust. The approved plan defines the minimum required air quantity for different mining sections and processes, minimum air velocities on the longwall face, location and frequency of methane tests, etc. The monitoring and tracking system, air courses and escape ways are updated routinely on the mine map. The air survey and ventilation model are used to assess any ventilation and mine plan changes.

Mine Plan
Shoal Creek uses the underground longwall mining method which requires certain geometry and size for economic extraction. The LOM plan is limited by the faults at the southwest and northeast, thin coal at the north, and old works at the south. The mine plan has a mine life of ten years (i.e., 2022 to 2031) with a projection of 39 million tons of ROM production and 18 million tons of saleable product. The average annual production is 3.9 million tons of ROM coal, and 1.8 million tons of saleable product with an average yield of 46%.

Mining Process
The typical longwall panel is 1000 feet wide equipped with a shearer, hydraulic shields, armored face conveyor, stage loader, crusher, etc. The shearer cuts a 36-inch thick web along the 1,000-foot-longwall face for every pass it makes. The cutting height is constrained by equipment size and ranges from 8.5 feet to 11 feet. Shoal Creek mines the Mary Lee and Blue Creek seams and the parting interval between the coal seams. Due to the variation of the coal thickness, the longwall sometimes cuts the rock from the roof or floor in order to maintain the minimum height required by the longwall equipment. The mining process generates considerable dilution from the parting, roof rock, and floor rock. The ROM coal, including coal and dilution, is crushed and conveyed to the washing plant for processing. Most of the dilution is separated in the washing plant from coal and then disposed of as refuse.

Continuous miners are used to cut the entries for mains and gate roads. A typical cut sequence includes eight cuts (four cuts on each side of the entry) with a maximum depth of 10 feet for each cut. The coal is transported by shuttle cars to the feeder breaker which reduces mined coal to a consistent, easily handled size for conveyance. After a maximum 40 feet depth cut, the newly exposed roof is to be supported according to the approved roof control plan. The Shoal Creek mine is scheduled to employ two continuous miner systems for the current LOM plan.

The coal mined at Shoal Creek mine includes high ash parting and out of seam dilutions. It needs to be washed prior to shipping to customers. The coal handling and processing plant at Shoal Creek was constructed in 1994 and has been utilized to size and clean the ROM coal to meet the quality requirements of customers.

Process Selection and Design
The operation has made additional upgrades to the original facility as needed. In the year 2020, the operation replaced Baum Jigs with Heavy Media Vessels (HMV), and added extra deslime and refuse screens, etc. The current facility has adequate capacity to meet projected production and quality requirements.

Coal Handling and Processing Plant
The ROM coal produced at Shoal Creek is transported from the underground mine by 72” belt conveyors, through an inclined slope to the Shoal Creek processing plant. The processing plant utilizes an A/B side configuration. Each side of the plant is rated at 1,000 Tons p ........