2
and high sulphides in the 68 L has generated a dichotomy
of low pH (acidic) and high pH (alkali) solutions and an
abundant amount of dissolved solids and precipitates.
Figure 1 shows the two characteristics of the water
from the Never Sweat Tunnel, TPL2 boreholes, and the
areas of highly corrosive and low ph efflorescent salts for
portions of the 68L. The water from the NST and from
the 68L boreholes waters show low to moderate dissolved
solids(salinity), and, therefore low corrosion potential. The
Hatch report (2018) from the 68 Level or TPL2 has shown
moderate dissolved solids ranging from 1,100–1,400nmg/L
the tendency to form Calcium Carbonate scale, and a high
tendency for steel corrosion.
Note neutral to slightly alkaline PH with varied dis-
solved solids. The DHRES06 and DHRES-09 samples
were collected outside the local orebody graben. Typical
water samples from deepwater wells such as DHRES-01
and DHRES-02 were located in the ore body, with neutral
to slightly alkaline PH with varied dissolved solids.
CURRENT TPL2(68L STUDIES)
More recently photographs and mineral precipitate samples
were taken for field and laboratory analysis on the TPL2 or
68 Level. As part of the study, 4 field paste pH mea-
surements and 7 solid samples were collected as well as
investigating and collecting photographic evidence of cor-
rosion. This sample testing is important in establishing the
background processes and chemical reactions that are influ-
encing corrosion. Table 2 is a summary of the testing of the
precipitates and the PH.
Figure 2 is a plan map of the 68-level showing where
the samples were taken, with an overlay of the percent total
Sulphur from the geologic block model. It shows a bimodal
distribution of extremely highly acidic in the PR bulk, PR2
and North Drift, and primarily neutral to alkalic in the
remainder of the drifts. Based on descriptions and pictures
of the underground conditions, considers that the alkaline
conditions that exist are associated with exposures of shot-
crete, whereas the acidic locations are influenced by the oxi-
dizing pyrite that is not protected by shotcrete. The higher
Table 2. Test Results of precipitates for electrical
conductivities and lab paste PH on 68L
Sample ITD
Primary
Color
Lab Electrical
Conductivity
(µmhos/cm)
Lab Paste
pH (s.u.)
VENT-BH-
FLAKE
White 12020 8.61
#9-WV White 11990 9.07
PR BULK Yellow/
Orange
7860 2.75
PR-2 Yellow 3850 0.73
NORTH
DRIFT
Yellow 3750 0.86
PR-1 White 3590 8.90
OLD-ER White 1095 8.69
Table 1. Typical water samples from deepwater wells.
DHRES01 and DRHES02 located in the ore body
Figure 1. Water samples, and corrosive environments based
on observations at RC. Information plotted on Aqueous
classification chart. From Logsdon, 2022
and high sulphides in the 68 L has generated a dichotomy
of low pH (acidic) and high pH (alkali) solutions and an
abundant amount of dissolved solids and precipitates.
Figure 1 shows the two characteristics of the water
from the Never Sweat Tunnel, TPL2 boreholes, and the
areas of highly corrosive and low ph efflorescent salts for
portions of the 68L. The water from the NST and from
the 68L boreholes waters show low to moderate dissolved
solids(salinity), and, therefore low corrosion potential. The
Hatch report (2018) from the 68 Level or TPL2 has shown
moderate dissolved solids ranging from 1,100–1,400nmg/L
the tendency to form Calcium Carbonate scale, and a high
tendency for steel corrosion.
Note neutral to slightly alkaline PH with varied dis-
solved solids. The DHRES06 and DHRES-09 samples
were collected outside the local orebody graben. Typical
water samples from deepwater wells such as DHRES-01
and DHRES-02 were located in the ore body, with neutral
to slightly alkaline PH with varied dissolved solids.
CURRENT TPL2(68L STUDIES)
More recently photographs and mineral precipitate samples
were taken for field and laboratory analysis on the TPL2 or
68 Level. As part of the study, 4 field paste pH mea-
surements and 7 solid samples were collected as well as
investigating and collecting photographic evidence of cor-
rosion. This sample testing is important in establishing the
background processes and chemical reactions that are influ-
encing corrosion. Table 2 is a summary of the testing of the
precipitates and the PH.
Figure 2 is a plan map of the 68-level showing where
the samples were taken, with an overlay of the percent total
Sulphur from the geologic block model. It shows a bimodal
distribution of extremely highly acidic in the PR bulk, PR2
and North Drift, and primarily neutral to alkalic in the
remainder of the drifts. Based on descriptions and pictures
of the underground conditions, considers that the alkaline
conditions that exist are associated with exposures of shot-
crete, whereas the acidic locations are influenced by the oxi-
dizing pyrite that is not protected by shotcrete. The higher
Table 2. Test Results of precipitates for electrical
conductivities and lab paste PH on 68L
Sample ITD
Primary
Color
Lab Electrical
Conductivity
(µmhos/cm)
Lab Paste
pH (s.u.)
VENT-BH-
FLAKE
White 12020 8.61
#9-WV White 11990 9.07
PR BULK Yellow/
Orange
7860 2.75
PR-2 Yellow 3850 0.73
NORTH
DRIFT
Yellow 3750 0.86
PR-1 White 3590 8.90
OLD-ER White 1095 8.69
Table 1. Typical water samples from deepwater wells.
DHRES01 and DRHES02 located in the ore body
Figure 1. Water samples, and corrosive environments based
on observations at RC. Information plotted on Aqueous
classification chart. From Logsdon, 2022