Landslide stabilization design for an underground coal mine

About this project

Mountain Coal Company
$12 million

At the West Elk Mine (an underground coal-mining operation on the western slope of the Colorado Rockies), the first indication of unstable slope conditions occurred during construction of the mine portals in 1980, and was thought to be localized and shallow. In early 1997, the landslide moved more than a foot in three months. Calculations showed that it was accelerating, threatening the mine facilities downhill. The Mountain Coal Company initiated an emergency action plan and asked Barr to investigate the landslide and design mitigation measures.

Barr’s team characterized the extent of the slide and the depth of the slide failure plane, as well as the area’s soil and groundwater, and determined that the slide was massive. We confirmed that groundwater was a key factor, so extensive dewatering measures were designed and constructed to provide long-term stability.

To reduce the immediate momentum of the slide, we designed a network of flexible steel pins. Typically, rigid pins anchored in bedrock would be used to stabilize a landslide, but these would be sheared off by the mass of this slide. Barr’s design uses pins made of steel pipe, which flex to prevent them from breaking while still resisting the landslide forces. Rather than being embedded in bedrock, the pins tie the faster-moving upper soil layer to the slower-moving layer below to provide a braking force. We continue to monitor and evaluate the landslide and have contingency plans ready if it reactivates.

Key team members

Phil Solseng

Vice President

Paul Schiller

Vice President
Senior Structural Engineer

Related design and construction projects

Park and landscape design for Mouse River enhanced flood protection project
Design of abutment wall extension at Dells hydro station
Phase I ESA for copper-nickel project
Coffee Creek trout stream restoration
Ore transportation study
Dry-stack tailings management
Permitting, environmental assessment, and design for copper-nickel mine
Tailings basin expansion and closure options
Investigation and remediation of jet-fuel release
Vapor intrusion investigation and mitigation in a residential neighborhood
Snowpack monitoring and lake drawdown for Minnesota watershed district
Geotechnical investigation and design for expansion of ancient gold mine
Penn Avenue sinkhole investigation and rehabilitation
Scoping study to increase magnetite-concentrate production capacity
Mine closure and reclamation
Geologic modeling and mine-plan development for aggregate quarries
Resource estimates for neodymium-rich rare-earth-element exploration project
Advanced oxidation process pilot evaluation for municipal drinking-water system
Waste-gas scrubber design engineering for taconite pellet plant
RICE applicability analysis and audit
Responding to wind-farm tornado damage
Upgrades and expansion for silica-sand wet plant
Reclamation of legacy tailings site
Evaluation of wind-turbine foundation following fire damage
Engineering services for frac-sand operation
Environmental review and prefeasibility design for planned uranium mine
Groundwater modeling for wellhead-protection-plan amendment
Multi-site PFAS remedial investigation and remediation
Sediment removal from beneath Vermillion River bridge
Monitoring of end-pit lake at oil sands mine
Highwall stability assessment
Flood risk reduction of suburban lakes
Letter of map revision for Minnesota city
Options study and design to restore biomass fuel-handling system
Mine remediation and reclamation
West River Parkway landslide repair
FERC relicensing of Ford Lake Dam
Tailings-management area design and construction
Spillway design for iron-ore-mining and mineral-processing facility
Groundwater compliance assistance for CCR Rule
Environmental site assessments for future site of mining and processing facility
Floodproofing of utility switchyard
Resource assessment and permitting assistance for industrial sands facility
Flood mitigation at refinery
Engineering services for industrial chemicals mine and processing facility
Wetland replacement assistance for highway project
Trona-mining production optimization
Environmental support for post-fire cleanup at industrial facility
Geotechnical assistance for mine expansion at Julienne Lake
Lilydale Regional Park stormwater management and slope stabilization
PFOS investigation at municipal wastewater plant
Response to denatured ethanol release
Compliance, resource, and process evaluations for potential mining sites
Aquatic invasive species (AIS) management in a Wisconsin lake
Solar-energy-system compliance
Berm-failure study at saltwater disposal well site
Preliminary feasibility study for PFAS-related water quality concerns
Rockford dam removal
Groundwater modeling and remedial improvements at closed landfills
Stressor-identification report for an impaired urban stream
Post-flood stream assessment and natural channel design
Preclassification system feasibility study, design, and construction support
Geotechnical highwall assessment at Bald Mountain
Above-ground tailings management and mine backfill
Water-quality and structural monitoring for channel dredging
Spillway redesign at Cedar Falls Hydro Generating Station
Flood risk management system upgrades and FEMA certification
PMF modifications at hydroelectric plants
PMF study for the Dead River
Analysis of microbial ecology in selenium bioreactor
Statistical analysis of coal-silo vibrations
PFAS mass balance and sample collection
Upgrades to mineral processing plant
Aggregate resource estimate along proposed pipeline routes
PFAS treatment during power plant decommissioning
TMDL study and water quality assessment for a suburban stream
Gas processing equipment, outage procedure and fitness-for-service evaluation
PFAS stack testing services for a manufacturing client
AWIA risk and emergency compliance for urban drinking water
Tailings dam safety inventory and semiquantitative risk analysis
Environmental assessment program for highway safety improvements
CFD modeling of stormwater tunnels
Carbon-evaluation services for new mining facilities
Engineering services for solution mine
Environmental services at manufacturing facility
Process and plant design for potash mine
Design of repairs to leaking reservoir
NEPA support for coal mine expansion
Trichloroethylene (TCE) investigation and remediation
RCRA waste tank inspection, certification, and closure
Redesign and optimization of crystallizer piping
Air permitting assistance for reaction-injection molding operation
Road raise and conceptual design
Water discharge permitting for copper-nickel mine
Reasonably available control technology analysis for refinery
Flood-control-system upgrades and certification
Landslide stabilization protects architectural treasures
Strategy for collecting lake-morphometry data
Closure and reclamation support for a legacy metals mine
Third-party dam safety review of tailings-storage facility
Tailings facility dam safety review
Wastewater antidegradation analysis and NPDES permit renewal
Comprehensive water audits at manufacturing facilities