Subject
Logging
33
Forest machinery
28
Machinery
27
Harvesting
12
Acid mine drainage
10
Coal
10
Environmental aspects
10
Forestry engineering
10
Mineral industry
10
Mining
10
Forest management
9
Research
9
Tailings
9
Forests and forestry
8
Log transportation
8
Reclamation
8
Testing
8
Evaluation
7
Sulfides
7
Beneficiation
6
Concrete
6
Environmental impacts
6
Forestry practices
6
Industrial minerals
6
Integrated Resource management
6
Waste disposal
6
Coal Mines
5
Combustion
5
Costs
5
Equipment and supplies
5
Methane
5
Ash
4
Clean coal
4
Coal mining
4
Emissions
4
Feasibility studies
4
Forest roads
4
Forestry machinery
4
Fuelwood
4
Longwall mining
4
Mines
4
Silviculture
4
Sulfur
4
Technology
4
Tree felling
4
Trees
4
Winches
4
Wood chips
4
Woodlots
4
Analysis
3
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