Pulacayo Project Feasibility Study - Apogee Silver

Pulacayo 1 000 t/d Phase I Feasibility Study - NI 43-101 Technical Report
090644-3-0000-20-IFI-100
pumps, piping and electrical systems are included in the paste plant and discussed in that section
of this report as well as the related costs reported in those cost areas. The tailings production by
year and the distribution between underground backfilling and discharge to the TSF are
summarized in Table 18.1. The allowance for underground disposal has used a series of
conservative assumptions and, as such, the quantity going to the TSF (and the resulting size of
the TSF) should be somewhat overstated. This approach ensures that there will always be
adequate TSF capacity and that the TSF operating cost estimates are conservative. On the other
hand, the basin has ample room for more tailings should additional capacity be needed.
Table 18.1: Tailings to the TSF by Year
Year
Annual Production
(x1,000 t)
Cumulative Production
(x1,000 t)
1 0 0
2 43 43
3 56 99
4 30 129
5 118 247
6 152 400
7 144 543
8 49 593
9 42 635
10 90 725
11 81 806
12 360 1,166
13 180 1,346
18.9.2 TSF Design Concepts
The TSF will be developed by first constructing four small starter dikes, one upstream of the other
and within the same drainage. Construction of the starter facility will start before commissioning
of the paste plant, and will continue concurrently with the paste plant during Year 1. This is to
allow placement of cement-treated tailings along the valley floor to seal the basin. The facility will
be expanded annually during the dry season by raising two dikes each year by 4 m. Below the
first dike (Dike 1) will be a small emergency pond and monitoring ports for the subdrain system.
The emergency pond is to manage surface waters that enter the TSF and has a working capacity
of 1,750 m 3 . The subdrain monitoring ports are to collect the discharge from the subdrains (to
allow testing and return to the TSF or emergency pond, as needed) with a working capacity of 15
m3 Figure 18.2 shows the ultimate general arrangement of the facility.
The tailings handling circuit, from the discharge of the paste plant to the TSF, will have the
following equipment:
TWP Sudamérica S.A. Av. Encalada 1257 Of. 801, Santiago de Surco Lima 33, Perú (51-1) 4377473
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