Pierre River Mine Project

MINING AND PROCESSING ERCB SIRS 3 – 38
Section 4.1
33a Based on the updated Table 218-4, what is the annual percentage of fines in Ore
Feed captured in thickened tailings (TT) deposit, i.e. excluding the thin fine
tailings (TFT) formed from TT stream, during 2018-2028?
Response 33a The fines captured in the TT deposit in the Pierre River Mine tailings plan are
summarized in Table ERCB 33-1. As shown in Table ERCB 33-1, the fines
capture averages 40% between 2018 and 2028.
Period
Table ERCB 33-1: Fines Capture in the Pierre River Mine ETDA TT Deposit
Total Ore
(t)
Extraction Ore Feed Thickened Tailings Deposit (3)
Course
(t) (1)
Fines
(t) (2)
Fines
wt%
Mineral
Course
(t) (1)
Fines
(t) (2)
Fines
(% of
Extraction
Fines)
2018 5.98 4.16 0.85 16.9 1.95 0.38 44.7
2019 19.02 13.22 2.69 16.9 0.93 1.03 38.5
2020 54.59 37.96 7.73 16.9 2.66 2.97 38.5
2021 66.51 46.44 9.45 16.9 4.43 3.67 38.9
2022 75.97 53.12 10.82 16.9 5.05 4.20 38.9
2023 114.51 79.80 16.24 16.9 10.61 6.41 39.5
2024 117.65 82.18 16.73 16.9 10.64 6.59 39.4
2025 109.68 76.19 15.51 16.9 9.34 6.09 39.3
2026 116.61 81.63 16.62 16.9 9.21 6.50 39.1
2027 116.08 81.03 16.50 16.9 7.67 6.41 38.8
2028 108.91 75.45 15.36 16.9 23.56 6.49 42.3
Total 905.51 631.18 128.49 16.9 86.05 50.76 39.5
Note:
1. Coarse refers to all mineral consisting of particle size greater than 44µm.
2. Fines refers to all mineral consisting of particle size less than 44µm.
3. Thickened tailings deposit includes all thickener underflow captured in the beach (excluding thin fine tailings
runoff), as well as all cyclone underflow “lost” from cell construction on the centreline dyke and captured in the
beach.
Request 33b Is the annual percentage lower or higher than 50%? If lower, what constraints
limit Shell’s ability to capture a minimum of 50% fines in feed in the TT deposit
between 2018 and 2028?
Response 33b The level of fines capture in thickened tailings deposits is currently constrained
by Shell’s understanding of the capabilities of this technology. Shell recognizes
that, at this stage, this level of fines capture, in isolation, will not meet the
requirements of Directive 074. Therefore, in order to meet the 50% capture
required, Shell will use supplementary technologies, such as:
• applying the appropriate thickener design
April 2010 Shell Canada Limited 4-33
CR029