Personnel Assessment
After graduating from an excellent mining university, you start your first job at a mining consultant. The current customer requests a perfect mine plan for his operation site. Your colleagues have finished the mine design and scheduling as well as the equipment selection. You are now appointed to assess the workers required and forecasted costs for the waste removal team and the ore mining team.
- Sales target: 400.000 t ore (crude) per year
- Strip ratio: 1:5
- 5 days/week, 12 public holidays, 30 days vacation, 8.7% absence (training, special vacation, sickness leave), 40% employee benefit costs
- Waste removal team
- 1 shovel, 5 trucks, 1 dozer
- Equipment-KPI: 800 t/h
- Selective ore loading team
- 2 shovels (1 loading, 1 sorting), 4 trucks
- Equipment-KPI: 400 t/h
| Classification | Base hourly wage [€/h] |
|---|---|
| Shovel operator | 31.05 |
| Truck driver | 27.84 |
| Dozer operator | 27.84 |
| Multi-equipment operator | 28.91 |
| General HD mechanic | 29.98 |
Approach:
Assess (a) requirements (propose a shift model and link equipment performance to personnel) and (b) costs (linked to manshifts).
Waste Removal Team
400kt of ore with 1:5 strip → 2,000kt of waste
Working hours per year: 365-2*52 (weekends) – 12 (public holidays) → 249 days
So, for equipment: 8033 t/day with 800t/h → 10 h/day
We usually have a factor to calculate manhours deriving from machine hours.
For employees: 249days/a – 30 days (vacation) = 219 days – 19 days (8.7%) = 200 days.
Now we find the ratio 249/200 → 1.245 ~ 1.25
➔ We need 10*1.25 = 12.5h/day
➔ Proposed shift model: 2-8
With this information we can find the costs:
2 shovel operators, 10 truck drivers, 2 dozer operators, 8h each:
= (2*31.05+10*27.84+2*27.84)*8 = 3169.44€/day (without employee benefit costs).
Assuming that we pay for public holidays and vacation → 3169.44*249 = 789k€/a and with 40% benefit costs → 1,105 k€ per year.
Alternatively: 2 shovel operators, 8 truck drivers, 2 multi-equipment operators, 8h each:
= (2*31.05+8*27.84+2*28.91)*8 = 2741 €/day (without employee benefit costs).
Assuming that we pay for public holidays and vacation → 2741*249 = 683k€/a and with 40% benefit costs → 956 k€ per year.
Ore Mining Team
It is the same operation, so we also have 249 days.
With ore equipment we need to move 400 kt → 1606 t/day and with 400t/h → 4h/day
Employee factor stays the same, so we end up with 4*1.25 = 5h/day.
➔ Proposed shift model is 1-6. If it is not possible to have different shift times, we need to take 1-8.
Now we can calculate the costs:
2 shovel operators, 4 truck drivers for 6 or 8 h/day:
=2*31.05+4*27.84=173.46 → for 6h: 1040€/day for 8h: 1387€/day (without employee benefit)
➔ For 6h: 363k€/a and for 8h: 484k€/a (with employee benefit).
