Wyoming Uranium Mine Reclamation: Equipment Strategies for Large-Scale Earthmoving Projects

Large-scale earthmoving projects demand careful planning, the right equipment fleet, and precise execution to meet deadlines and budgets. The McIntosh Pit uranium mine reclamation project near Jeffrey City, Wyoming demonstrates how contractors can combine specialized machinery with strategic scheduling to move millions of cubic yards of material efficiently. Understanding the Key Facts About Construction Project Life Cycle Phases helps contextualize how a seven-phase, $26.2 million abandoned mine land reclamation program unfolds over nearly a decade. This article examines the equipment strategies, operational techniques, and project management approaches that made phase five of this Cold War era cleanup a success.

The Historical Context and Project Scope of the McIntosh Pit Reclamation

From Cold War Uranium Boom to Abandoned Mine Site

The McIntosh Pit sits on Sheep Mountain in the Crooks Gap-Green Mountain Uranium Mining District of Freemont County, Wyoming. During the Cold War, the U.S. government identified a critical need for domestic uranium sources to fuel the atomic arms race with the Soviet Union. Prospector Bob Adams strapped radiation detectors to the wings of his private plane and flew over the Wyoming hills, successfully locating uranium deposits in Crooks Gap. In 1958, Adams partnered with Dr. Charles W. Jeffrey’s Western Nuclear Corporation (WNC) and secured a contract from the U.S. Atomic Energy Commission that doubled the company’s uranium milling capacity.

This discovery triggered a population and economic boom. Jeffrey City grew from a remote highway stop into a community of over 4,000 residents. WNC began open-pit mining operations at the McIntosh Pit in 1975, extracting over four million tons of ore from the 35-acre site. The Split Rock uranium mill processed 1,700 tons of ore daily using acid leach, solvent extraction, and ion exchange methods to produce yellowcake concentrate. The boom ended abruptly in 1979 following the Three Mile Island partial meltdown. Stricter nuclear regulations and collapsed demand for uranium forced WNC to lay off hundreds of employees. By the end of 1982, production ceased entirely, and the mine was abandoned. Without reclamation requirements before the Surface Mining Control and Reclamation Act of 1977, the site sat unremediated for decades. Jeffrey City’s population fell to just 58 residents.

The Seven-Phase Abandoned Mine Land Program

In 2014, the Abandoned Mine Land (AML) Program administered by the Wyoming Department of Environmental Quality (DEQ) launched a $26.2 million, seven-phase plan to restore the McIntosh Pit to its pre-mining landscape. Engineers created computer-generated 3D models to guide the restoration. The program objectives included:

• Abating physically dangerous hazards across the site
• Improving drainage and stabilizing landforms
• Remediating 12 million cubic yards of mine spoils containing elevated radionuclides
• Establishing diverse native vegetation for livestock grazing and ecological recovery

Phase five, awarded to Summit Excavation and Grading (Summit) in April 2020, required moving 1.2 million cubic yards of material from the hillside into the bottom of the 200-foot-deep pit, eliminating the groundwater lake that had formed within the excavated walls. The eight-month project targeted an aggressive average weekly production of 50,000 cubic yards. The Construction Project Scheduling Methods Tools and Best Practices used by Summit were critical to meeting this deadline in the challenging Wyoming terrain.

Equipment Selection and Configuration for High-Volume Earthmoving

Train Scraper Configuration: Doubling Payload Per Operator

Summit chose a unique equipment strategy that differed from previous phase contractors who used mining shovels, excavators, or traditional motorized scrapers. The company deployed two Volvo 40-ton articulated dump trucks (ADTs), each pulling two K-Tec 1237ADT scrapers in a train configuration. This setup allowed a single operator and engine to haul 74 cubic yards per pass, with 37 cubic yards per scraper. The K-Tec 1237ADT scrapers featured an aggressive center bit cutting edge stinger that enabled deep excavation and rapid loading in the abrasive powdered granite material.

Key specifications of the train scraper configuration included:

Loading and Haul Operations

The operation used the site’s natural topography to advantage. Loading began at the top of the spoil pile cliff, where operators used gravity to dive down the steep grade. The lead scraper loaded first, followed by the rear scraper achieving a heaped load before reaching the bottom of the slope. Summit Owner Mark Schmidt noted that the scrapers’ 14-foot width and four-wide wheel arrangement provided exceptional stability on slopes up to 3:1 gradient. The loaded trains, fitted with eight-caliper disc brakes, sped down an eight percent grade on the freshly constructed winding haul road. On level ground, loaded scraper trains traveled approximately 34 miles per hour. Once at the pit bottom, scrapers drove parallel to the shoreline and dumped each scraper within eight seconds. A Caterpillar D8 dozer pushed the material into the standing water, progressively squeezing it out. Full cycles averaged 7.5 minutes, enabling Summit to maintain the 50,000-cubic-yard weekly target.

Boulder Management and Material Handling

The buried granite mine site concealed boulders that could damage scraper cutting edges. When hidden rocks were encountered, an excavator moved in to pluck out the massive stones and deposit them into a Volvo A40G truck fitted with a K-Tec EJB 4X ejector body. The truck traveled down the winding haul road and smoothly ejected the boulders into the groundwater lake. This system kept the scraper fleet productive without interruptions for rock removal. To safely manage the groundwater level, a series of evaporation mist arrays and water cannons were positioned on the water surface and around the reservoir banks, offsetting displacement as fill material entered the pit.

Haul Road Maintenance and Support Equipment Coordination

The Earthmoving Support Tractor: A Multi-Function Asset

Summit deployed an Earthmoving Support Tractor (EST) built around a Case tractor power unit with two K-Tec attachments. On the front, the Ox Block pusher block push-loaded scrapers for increased capacity in the cut zone. On the rear, the K-Tec Tricerabox delivered three functions through a single three-point hitch-mounted box blade:

• Leveling blade pulls material forward to smooth surfaces
• Ripper teeth with seven hydraulically operated shanks pre-rip excavation and expose boulders
• Back blade pushes material for backfilling and smoothing cut and fill zones

The EST’s three-point hitch was modified with a scraper hitch hook-up, allowing the tractor to function as a bulk dirt hauler when another power unit was down for maintenance. A second Case tractor with a K-Tec 1233 scraper outfitted with a Trimble GPS system handled short-haul material from the southern spoil, channel work, local fills, slope work, cover soil placement, and finish grading. The Construction Project Life Cycle Phases in Life Cycle framework illustrates how support equipment planning fits into the broader execution phase of large reclamation projects.

Haul Road Maintenance as a Productivity Driver

Summit placed heavy emphasis on haul road quality as a direct contributor to both efficiency and safety. A Case 620 tractor pulling a 20-foot-wide K-Tec land leveler continuously maintained the winding eight percent grade road surface from the east spoil pile to the pit bottom. A water truck provided dust control through frequent moisture application. The maintenance workflow followed a repeating sequence:

1. Case 620 tractor pulls the K-Tec land leveler along the full haul route
2. Blade smooths surface irregularities and ruts from the previous cycles
3. Water truck applies moisture for dust suppression and compaction
4. Load cycles resume on the groomed surface for maximum speed

On the smooth maintained surface, loaded scraper trains reached approximately 34 miles per hour, significantly reducing cycle times compared to rough roads.

GPS Grading, Topsoil Management, and Final Restoration

GPS-Automated Precision Grading

GPS automation enabled precise grade control on both subgrade and finish grading, meeting the strict elevation requirements of the 3D model that defined the pre-mining landscape. This technology eliminated manual staking and reduced rework, accelerating the overall schedule and ensuring the final contours matched the original topography. Both the subgrade and finish grades were put in by GPS automated machines.

Topsoil Management and Ecological Restoration

Throughout the project, Summit strategically stockpiled topsoil while the subgrade was exposed. After the subgrade work reached design elevation, the topsoil was hauled and spread using scrapers on open areas and the EJB in challenging locations. The final spreading of brown topsoil over the Wyoming sand provided a fertile growing medium for native plant species. A landscaping subcontractor planted native vegetation, which took root near the end of phase five. The result is that future generations will see no visible trace of the uranium boom and bust across these acres of Crooks Gap. Cold in Place Recycling for Full Depth Reclamation follows a similar principle of combining mechanical processes with environmental controls to achieve stable, long-lasting results in challenging site conditions.

Lessons for Earthmoving Contractors

The McIntosh Pit reclamation offers practical insights for contractors planning large-scale earthmoving operations. Summit’s approach demonstrated several principles applicable to heavy civil and mining reclamation projects:

1. Train scraper configurations double payload without doubling labor A single operator hauling 74 cubic yards per pass versus 37 cubic yards significantly improved labor productivity and reduced fuel consumption per cubic yard moved.
2. Haul road maintenance directly determines cycle time Continuous grading and dust control allowed loaded travel speeds of 34 mph, essential for achieving the weekly production target.
3. Multi-function support equipment reduces fleet complexity The EST with Ox Block and Tricerabox replaced several specialized machines with one versatile unit, simplifying maintenance and operator training.
4. GPS automation improves accuracy and reduces survey costs Trimble-guided grading eliminated manual staking and ensured the final surface matched the 3D model without expensive rework.
5. Planned material handling prevents downtime The excavator and EJB boulder removal system kept scrapers productive instead of idling while rocks were cleared.

Summit completed phase five of the McIntosh Pit uranium mine reclamation on time, using Volvo ADTs, K-Tec train scrapers, GPS-guided grading, and versatile support equipment. What began as a Cold War-era mining site has been systematically returned to productive rangeland through disciplined project phasing, smart equipment selection, and meticulous operational execution.