EIS 296
Report, geotechnical investigation, lowwall & spoil pile stability,
proposed surface coal mine, Mt. Thorley, N.S.W. for R.W. Miller
& Co. Pty. Ltd.
MSW DEPT PRIMARI iUSTR1ES
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D*ES a. MOICME CONSULTANTS IN THE ENVIRONMENTAL
AND APPLIED EARTH SCIENCES
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1 1 I I I REPORT
GEOTECHNICAL INVESTIGATION
ILOWWALL & SPOIL PILE SThBILITY
PROPOSED SUEFACE COAL MINE
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MT. THORLEY,
1 FOR
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R.W. MILLER & CO. PTY LTD.
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I DRAFT I
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I DAMES & MOORE
I JO B NO: 10236-00170
DATE: JANUARY 1978
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PERTH MELBOURNE SINGAPORE DAMES & MOORE JAKARTA
CONSULTANTS IN 'THE ENVIRONMENTAL AND APPLIED EARTH SCIENCES LONDON TOKYO MADRID VANCOUVER TEHRAN TORONTO JOHANNESBURG CALGARY
PRINCIPAL CITIES IN THE U.S.A.
7 MYRTLE STREET. CROWS NEST, N.S.W. 2065. AUSTRALI A
TELEPHONE 929.7744 TELEX 21378 CABLE AODRESS DAMEMORE
January 24 1978
R W Miller & Co Pty Ltd 237 King Street NEWCASTLE N S W 2300
Attention: Mr Peter Murray General Manager - Mining
Dear Sir
Enclosed are five draft copies of our report " Geotechnical Investigation, Lowwall and Spoilpile Stability, Proposed Surface Coal Mine, Mt. Thorley, N S WI'.
This is the second of two reports issued following our geotechnical investigations at Mt. Thorley. The final version of the first report on highwall stability was issued on January 23 1978. We would be pleased to receive any comments you might have on the contents of the draft. If we have not received any comments by February 7 1978 we will issue the reports in final form unchanged from the draft.
Yours faithfully DAMES & MOORE
I-,&. A C LEGGO Principal-in--Charge
MEMBERS OF THE ASSOCIATION OF CONSULTING ENGINEERS AUSTRALIA
TABLE OF CONTENTS
Page
1.0 INTRODUCTION 1 1.1 General 1.2 Proposed Development
2.0 GEOTECHNICAL STUDY 2 2.1 Objectives 2.2 Method of geotechnical study
3.0 MINE PLAN 5
4.0 SITE CONDITIONS 6 4.1 Geology 4.2 Hydrology
5.0 HIGEWALL STABILITY - WESTERN ZONE 6
6.0 LOWWALL STABILITY 7 6.1 General 6.2 Lowwall stability - Eastern zone 6.3 Lowwall stability - Western zone
7.0 SPOIL PILE STABILITY 9 7.1 Nature of spoil 7.2 Geometry of spoil piles
7.2.1 Spoil in Open Cut 7.2.2 Spoil in permanent spoil piles
7.3 Nature and slope of spoil pile floor 7.4 Water conditions
8.0 PIT FLOOR STABILITY 12
9.0 GROUNDWATER CONDITIONS 13 9.1 General 9.2 Estimated groundwater flows into pit
10.0 OVERBURDEN EXCAVATION CHARACTERISTICS 14
11.0 CONCLUSIONS AND RECOMMENDATIONS 15 11.1 Highwall stability - Western zone 11.2 Lowwall stability - Eastern zone 11.3 Lowwall stability - Western zone 11.4 Spoil pile stability 11.5 Groundwater inflows 11.6 Overburden excavation
LIST OF FIGURES 19
Figures 1 to 10
APPENDIX 20 to 24
LIST OF APPENDIX FIGURES 25
Figures Ala to A21
Eli 1.0 INTRODUCTION
1.1 General
Thisis the second of two reports presenting the results of geotechnical
studies carried out to obtain data on:
- Stability of highwalls, lowwalls and spoilpiles
- Groundwater regime and effect on mining
- Characteristics of material with respect to drilling, blasting, excavation.
- In order to facilitate mine planning studies, our initial report, on stability
I of highwalls in the eastern Zone, was submitted separately, on 14 November
1977. This report presents the results of the remaining aspects of the study.
by Mr Peter Murray The work performed during this study was authorized under
R W Miller & Co Pty Ltd purchase order no MT C 0076096. The original scope
of the study was outlined in our proposal dated 11 February 1977. The scope
was later expanded to include a geotechnical study of the western zone.
I It should be noted that some of the following sections of this report are
identical to those under the same heading in the first report. They are
repeated here for the sake of completeness.
1.2 Proposed Development
The Mt Thorley lease area is shown on Figure 1. It is an area of about 25
square kilometrs, located about 11 km southwest of Singleton.
Current plans involve initial mining in the eastern zone, commencing
immediately to the west of the "Mt Thorley Fault", with a possibility of
later mining in the western zone. The seams to be mined in the eastern zone
are the Glen Munro/Woodlands Hill, the Mt Arthur and the Piercefield, while
the Whybrow seam would be mined in the western zone. The two major seams,
theGlen Munro/Woodlands Hill and the Piercefield, average about 8 m and 16 m
in thickness, respectively.
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Initially, the Glen Munro/Woodlands Hill seam will be mined as a single
seam operation, on a contract basis. Mining will commence at the 8 m cover
I line and overburden will be dumped in permanent spoil disposal areas to the
east of the "Fault". This will allow later access to the deeper seam. The
seam will be mined on a long north-south face with advance down dip to the
1 west at the rate of about 30 m to 50 m per year. This operation will be
aimed at production of about 400,000 to 600,000 tonnes of washed coal per
I year.
I It is anticipated that at the end of the contract period, about three years,
the highwall will be a maximum of 25 m in height. The mining operation in
I the eastern zone to which this report primarily relates, however, is the
multiple seam mining of the Glen Munro/Woodlands Hill, Mt Arthur and Pierce-
field seams. This operation will commence some time after commencement of
I the contract upper seam operation.
2.0 GEOTECHNICAL STUDY
2.1 Objectives
The primary objective of the geotechnical study was to obtain representative
I data on the geotechnical parameters which will have an influence on the
design and operation of the open-cut mine. These parameters include:
I - GrouxLdwater regime - existing levels, fluctuation with seasonal rainfall; estimation of aquifer properties
I - Engineering geology of zone to be mined - presence and nature of faults, shear zones, joints, structural unconformities, etc
I - Geomechanical properties of material to be removed, shear strength, tensile strength, durability.
The above parameters were obtained in order to allow an assessment of the
following:
I - Need for and extent of dewatering of pit due to presence of groundwater. Effect of dewatering on source aquifers
I - Stability of the highwall, particularly in zones where overburden is weak. Need for flattening or benching highwall
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- Lowwall and spoilpile stability. The aim here was to assess whether such problems are likely to occur, rather than to investigate them in the detail
I necessary to provide solutions
- Characteristics of material with respect to drilling, blasting, excavation.
As mentioned earlier, the highwall stability aspects of our study were covered
in our first report. This report covers the other aspects noted above.
It should be pointed out that the geotechnical study was aimed at providing
I input into the detailed pit planning study. Its primary objectives were to
highlight potential problem areas of geotechnical significance; e.g. ground-
I water control; weak mudstone layers immediately beneath major seams which
could present floor heave problems or spoilpile stability problems; weak or
I badly jointed overburden materials which could present highwall stability
problems, etc.
It was not practical or advisable to attempt detailed analyses of these
problem areas or to develop comprehensive solutions at this feasibility stage
of the development, where a decision has yet to be made on whether the
development will go ahead and if so exactly which areas would be developed
and in what sequence. We would develop basic recommendations only. More
detailed recommendations could only be made once the mine plan were more
fully developed.
2.2 Method of Geotechnical Study
An extensive coal exploration drilling program was carried out by R W Miller
I & Co from February to November 1977. This program consisted of the coring
of approximately 95 holes, the locations of which are shown on Figure 1.
I The depths of the holes varied. The majority of the holes in the eastern
zone were taken to the base of the Piercefold seam (depth 150-200 m). Selected
I holes were taken deeper for correlation of the upper coal measures with
deeper reference strata.
For extraction of geotechnical data, we selected six holes in the eastern zone
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and three in the western zone as being representative of each area. The holes
selected were:
Eastern zone: BB24 X24
BB28 X28
BB32 X32
Western zone: L24
L32
028
For each hole we prepared an engineering geological log, from the surface to
below the seam(s) to be mined, generally to a depth of about 200 m for the
eastern zone and to a depth of about 100 m in the western zone. The logs for
holes BB24 to X32 were included in the first report. The logs for holes L24,
L32 and 028 are included as Figures A2 to A14 in the Appendix of this report.
The logs were prepared from field logging performed by our field engineers,
who carried out the following tasks:
- Noted all defects, including joints, shear zones, bedding partings, clayey
bands
- Noted the extent of surface weathering
- performed point load strength tests at regular spacing
- Recovered selected samples for laboratory testing.
In addition, surface weathering data were obtained from other selected holes
in the eastern zone and some samples were recovered from other holes for
laboratory testing.
Slotted PC standpipes were installed in the following holes: AA31, BB24,
I BB28, BB32, L24, L32, X24, X28, X32 and Z28 to allow long-term monitoring
of groundwater levels.
I The following laboratory tests were performed on selected samples to obtain
I data on the rock properties:
- Uniaxial (unconfined) compression tests to evaluate the strength of intact
Irock
- Direct shear tests ("Hoek" shear box tests) to measure the shear strength
of discontinuitieS, including bedding planes and joints
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- Direct shear tests (soil shear box tests) to measure the shear strength of weathered, soil-like material
- Moisture content and density tests
I - Slake durability tests.
I The results of the laboratory testing are included in the Appendix.
1 3.0 MINE PLAN
I The details of the mine plan for the eastern zone currently available have
been extracted from a report presented to us by Kinnaird Hill de Rohan &
Young, titled "Preliminary Study for Coal Mining Operations at Mt Thorley"
I dated October 1977. The report indicates that the optimum mine plan would be
a shovel and truck operation using up to four stripping shovels with a
I possibility of using a dragline to replace the bottom truck/shovel spread.
Figure 2 shows a schematic view of the pit after four years of operation.
I This plan is based on an initial rate of production of 1.5 million tonnes of
raw coal per year increasing to 3 million tonnes per year after two years.
I After six years, the rate of production will be increased to the maximum of
4 million tonnes per year.
Figures 3 and 4 show typical cross sections through the pit. As shown, the
pit will not have a lowwall in the usual sense; the Piercefield seam
I outcrops adjacent to the "Mt Thorley Fault" where it has been dragged upward
so that the dip of the seam near crop is about 50°. Essentially, the floor
I of the seam will form the lowwall; it will be benched to produce a similar
profile geometry to the highwall. Kinnaird Hill have indicated that they are
I considering an overall slope of 360 to 45
0 for the lowwall.
I No details of the mine plan for the weatern zone are available as yet.
Basically, the Whybrow seam would be mined in this zone, involving mining to
I depths up to 100 m. It is assumed that similar highwall, lowwall and soil
pile geometries as are planned for the eastern zone would apply.
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I 4.0 SITE CONDITIONS
1 4.1 Geology
The strata dip generally at between 1:10 and 1:20 in a direction about 30°
I south of west. However, the dip increases sharply in the eastern part of the
site, in the vicinity of the "Mt Thorley Fault", where the dip increases to
up to about 500. East of the fault, the marine strata of the Maitland Group
crop. As a result, the fault structure establishes the eastern limit for
I coal potential in the lease area. No other significant faulting has been
indicated by drilling in the eastern zone.
4.2 Hydrology
To our knowledge, there have been no hydrologic studies performed in the
area. The only available data at present are groundwater measurements from
I the seven boreholes in which standpipes have been installed.
I Groundwater levels have been monitored in these borings since July 1977 and
the readings are tabulated on Figure 5 . Results of this monitoring show
I that groundwater levels stand at between 7 m and 32 m below the ground
surface.
5.0 HIGHWALL STABILITY - WESTERN ZONE
The discussion on highwall stability presented: in the first report applies
equally to the highwalls in the western zone. The logs of the holes in this
I zone which were logged by Dames & Moore (L24, L32, 028) are included in the
Appendix.
I In general, the overburden conditions revealed by the logs are similar to those
I found in the eastern zone. The comments and recommendations included in our
first report can be taken as being applicable to the western zone.
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6.0 L0WALL STABILITY
6.1 General
The factors which affect the stability of the lowwall are the same as those
affecting the stability of the highwall, namely:
- strength of rock mass
- orientation and character of discontinuities
- groundwater conditions
- seismic and blasting effects
- surface loads
- mining procedures.
I The comments made in the report on highwall stability apply equally to the
stability of the lowwall, with the exception of orientation and character of
I discontinuities. Consequently, the comments on the other factors will not
be repeated here.
Kinnaird Hill have indicated that they are planning the lowwall geometries as
shown on Figure 3 with an overall slope of about 360. They have indicated
however, that they are considering steepening the overall slope of the
lowwall to 450 .
6.2 Lowwall Stability -Eastern Zone
In the eastern zone, the most significant geotechnical feature affecting the
stability of the lowwall is the relative steeb dip of the strata in the
vicinity of the "Mt. Thorley Fault".
In flat bedded strata, the stability of the rock face is not significantly
affected by the dip of the strata - it is more dependent upon frequency
and nature of joints, sheared zones, rock strength, etc (refer to report
on highwall stability). However, where the strata are not flat-bedded, as
is the case in the vicinity of the lowwall, the dip of the bedding must
be taken into account in designing the geometry of the rock face.
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From the point of view of overall stability of the lowwalls, they should be
I formed so that their overall slope should be no steeper than the dip of the
strata, to preclude the possibility of a sliding failure along bedding. In the
I case of the Mt. Thorley strata, strength along bedding is generally high. However,
occasional weak seams occur which could present overall stability problems if
the bedding "daylighted" out of the lowwall face.
We understand that the mine planners, Kinniard Hill, are contemplating overall
I lowwall slopes of 360. As shown on Figure 3*, this is flatter than the dip of
the strata for lines 24 and 28 and slightly steeper for line 32. Further south
I of line 32 the strata dip is slightly flatter than the slope of the lowwall.
This increase in dip of the strata to the south is due to the fact that the
I crop of the seam becomes further distant from, and thus less affected by, the
fault to the south. However, where the dip of the seam is flatter than the
I slope of the lowwall in the upper portion of the seam, the lowwall slope will
necessarily be dictated by the slope of the seam. It is assumed that, while
the upper portions of the lowwall will be formed at 360 or the slope of the seam,
I which ever is less, the lower portion would follow the dip of the seam and
flatten out accordingly.
If the lowwalls are formed in this way, the overall slope of the lowwall will
I be no steeper than the dip of the strata and overall stability would be adequate.
However, the possibility of some bench failures would still eXist. This is due
Ito the fact that individual bench faces, formed at about 700, are much steeper
than the dip of the strata. As a result sliding failures of benches along bedding
which "daylights" in the bench face could occur. Bench failures can occur during
I blasting or later during the lifetime of the pit, as the quality of the rock
deteriorates. Failures of individual benches could only be eliminated by flatten-
I ing bench faces to an angle equal to or flatter than the bedding dip.
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* It is noted that the plane of each of the lines 24, 28 and 32 is not
perpendicular to the cut. The true dip of the strata in relation to the
lowwall is slightly greater than shown on Figure 3.
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I 6.3
Lowwall Stability - Western Zone
The above comments refer to the lowwall in the eastern zone. We have not
yet been provided with details of the mine plan for the western zone.
However, since the Whybrow seam is not influenced by a fault as is the
Piercefield, the height of the lowwall will be significantly less than in
the eastern zone. In addition, the dip of the strata out of the highwall
will be only on the order of 6 0.
As a result, significant lowwall staolty
problems are less likely to occur in the western zone than in the eastern
zone.
7.0 SPOIL PILE STABILITY
The primary factors influencing the stability of the spoil piles will be:
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nature of spoil
- geometry of spoil pile
- nature and slope of spoil pile floor
- water conditions.
I 7.1 Nature of Spoil
I The spoil will consist primarily of competent sandstone and siltstone rock
fragments, from sand to boulder size but primarily of cobble size with minor
conglomerate and claystone.
We have performed slake durability tests to evaluate the extent to which the
I overburden rocks will be effected by exposure to the elements and to handling.
The test results are included in the Appendix. The tests indicate that the
I durability of the spoil will be high and that the majority of the rock will
not significantly break down during the life of the mine. The exceptions to
this general rule are the near-surface weathered rocks and the occasional
band of carbonaceous siltstone found adjacent to the coal seams. Since these
I rock types represent such a small proportion of the total overburden, their
presence should not be significant.
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7.2 Geometry of Spoil Piles
7.2.1 Spoil in Open-Cut
It is our understanding that the spoil will initially be dumped in permanent
spoil disposal areas to the east of the "Mt Thorley Fault" on non-coal bearing
land. Once the pit has advanced sufficiently far westward to provide enough
space, spoil will then be dumped directly into the pit. The face of the
spoil will then advance with the highwall.
Kinnaird Hill, the mine planners, advise that they anticipate that the final
level of the top of the spoil pile will be 45 m above the existing surface
level. The spoil will be benched, with maximum bench heights of 45m and
bench widths of 37 m. The benches would be located at the same levels as
selected highwall benches. The geometry of the spoil pile face resulting
from such requirements would be as shown on Figure 4, with an overall slope
of about 26°. This is based on the assumption that the dumped spoil will lie
at an angle of repose of 370 - 380 , which is typically the case in rocks of this
type.
7.2.2 Spoil in Permanent Spoil Piles
The geometry of proposed permanent overburden spoil piles is detailed in the
Environmental Standards Report*. This report shows the spoil piles to have a
surface slope of 1:10 (vertical:horizontal) with a benched perimeter slope of
about 220. They will be constructed on terrain with maximum slopes of about
1:20. Based on this geometry, and the compaction to be employed, we see no
reason to anticipate stability problems with these spoil piles.
I * "Report on The Environmental Standards and Alternatives for the Mount Thorley
Colliery", by James B. Croft & Asslociates, August, 1977.
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7.3 Nature and Slope of Spoil Pile Floor
The nature of and/or slope of the floor of the pit is often the major factor
leading to spoil pile instability. Often, the material immediately underlying
the coal seam. i.e. the material which forms the floor of the pit after the
coal is removed, is weak and/or becomes weaker on exposure to air and/or water.
Claystone bands of relatively low strength were encountered beneath the
Piercefield seam in some of the boreholes. However, in the majority of the
holes, the coal floor material is competent. Figure 5 shows a summary of the
material logged beneath the Piercefield seam in representative boreholes.
Based on this data, and on our knowledge of the geology of the area, we do
not consider such seams to be continuous beneath the Piercefield seam (or
the Glen Munro/Woodlands Hill or Mt Arthur seams).
Slake durability tests performed on samples of seam floor material show that
it does not break down significantly under exposure to air and water
indicating that, in general, the pit floor will be competent. It should
be ntoed however, that some of the core from beneath the Piercefield seam
was very weak (claystone) and was not suitable for slake durability
(or strength) testing. (See Figure 5).
The base of the spoil pile will generally dip at an angle of 30-6
0 toward the
highwall, the latter being the dip of the Piercefield seam. This degree of
dip applies only in the area to the west of the "Mt. morley Fault" and a;ay
from its influence limuediately to the west of the fault, however, the dID
of the seam increases up to 500. -
Generally, the steep sections of the seam will form the lowwall of the pit.
However, there will be a zone of transition between the base of the lc;c;all
and the evenly sloping pit floor. The slope of this zone will vary be.ween 0 0
say, 6 and 15
It will be important to ensure that benching of the lowwall extends through
this zone of transition slope, otherwise a major source of potential
instability could be created.
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I 7.4 Water Conditions
I The presence of excessive water in spoil piles can seriously affect their
stability. This can occur when the nature of the rock comprising the spoil
is such that .t weakens when exposed to air and water (eg. clay shales)
and/or the water has a similar effect on the competence of the floor material.
Based on the evidence from the slake durability tests (results shown on
Figures A15, A16 in the Appendix), and as mentioned previously, the over-
burden rocks at Mt. Thorley will generally be highly resistant to weakening
on exposure to water.
Another way in which water can affect spoil pile stability is by saturating
the spoil, with the resulting buoyancy effect reducing the effective
frictional strength. To prevent this occurring, care should be taken at all
times to maintain the geometry of the spoil piles in such a way that rain
water ponding, which leads to seepage into the spoil, is avoided. This
can be done by grading the benches so that surface water is drained off
into the pit. If this procedure is not sufficiently effective, it may be
necessary to consider lining the drainage ditches to maximise run-off.
8.0 PIT FLOOR STABILITY
Pit floor stability problems can occur in surface mines, usually being
manifested by floor heave. This uplifting of the floor is usually the result
of the presence of a layer of relatively weak, fine-grained material beneath
the coal seam, which forms the floor of the pit. This material is of ter
I further weakened by exposure to air and water and, being relatively impermeable,
can be subjected to high groundwater uplift forces. Either of these factors,
I or usually a combination of the two, can result in buckling of the floor,
presenting operational problems.
I As mentioned previously, at Mt. Thorley, the material underlying the Piercefield
seam are generally competent and does not significantly break down on exposure.
1 Also, the permeability of the floor material would not be significantly lower
than that of the deeper rocks, so that major hydrostatic uplift forces
should not be generated.
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9.0 GROUNDWATER CONDITIONS
9.1 General
The groundwater conditions at Mt. Thorley have been investigated by monitoring
groundwater levels in standpipe piezometers installed in selected boreholes,
and by performing pump-out tests in selected holes. The details of this
program are included in the Appendix.
Examination of the core and borehole logs and experience with coal measures
I rocks indicate that the coal seams form the primary groundwater aquifer
layers; i.e. the permeability of the coal is much higher than that of the
enclosing rocks. In such a case, where a particular layer forms a "confined
I aquifer", the water in the layer can be at artesian pressure. This depends
very much on the source of water "feeding" the aquifer and the relative
I permeabilities of the aquifer and the enclosing rocks.
Our investigations indicate that the water in the coal seams is not under
artesian pressure but under normal hydrostatic pressure dictated by the
I level of the standing water table. This is illustrated, for instance, by
the fact that in drilling observation wells adjacent to existing boreholes
I which extended through the main coal seams, the groundwater table was
encountered at about the same level as the water level in the borehole
through the seams.
9.2 Estimated Groundwater Flows into Pit
The pump-out test results in holes BB28, BB30 and BB32 are shown in the
Appendix. Our estimated groundwater inflow rates for varying pit dimensions
and at varying times after opening-up of the pit are shown on Figures A20, A21.
Accurate prediction of pit inflow rates from a limited program of pumP-cut
testing is difficult. The prime object of the field program was to provide
an indication of the order of magnitude of flow rates and the test results
allow such a prediction. We estimate that, for a pit of length 1500m and
base width of 30m, an average groundwater inflow rate of 300,000 litres per
day can be expected for the first several years of operation.
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This represents the combined flow from the Glen Munro/Woodlands Hill and
Piercefield seams. The test data indicates that the transmissibility, or
groundwater out-flow capacity, of the Piercefield seam is proportionally
larger than the Glen Munro/WoodlandS Hill seam by its seam thickness as it is
assumedthat the permeability of the coal in each of the two seams is the same.
It is thus concluded that the transmissibility of the lower seam is twice that
of the upper seam.
The rate of flow of water out of the seam will drop off as the "driving"
head is reduced. This is due to the fact that, being a confined aquifer,
with relatively impermeable enclosing rocks and no significant source of
recharge, the seam will eventually be drained of its contained water. It
is not possible to make an accurate estimate of the time required for each
seam to effectively drain, based on the presently available data, but we
would estimate that this would occur over a period of some years.
10.0 OVERBURDEN EXCAVATION CHARACTERISTICS
The most efficient means of removing overburden depends on the following
factors:
- strength of material fabric
- occurrence of planes of weakness.
As has been mentioned previously, the (fresh) rocks at Mt. Thorley are of
relatively high strength with relatively low occurrence of bedding partings
and weak bands. while the jointing pattern has not been established from
core logging, the majority of joints are likely to be vertical to sub-vertical
and generally spaced in the order of 0.51n to 2m.
The fresh rocks will require drilling and blasting to allow shovel excavation.
The extent of surface weathering, which reduces the rock strength so that it
can be removed without blasting, is shown on the borehole logs as well as on
Figures 6, 7 and 8. While the performance of trial excavations is the most
reliable means of determining the most efficient means of overburden removal,
the strength and fracture spacing data shown on the borehole logs allows a
prediction of the excavation characteristics, using published procedUreS*.
* Ref: J.A. Franklin, E. Broch & G. Walton "Logging the Mechanical Character
I of Rock", Trans. Inst. of Mm. & Metall., London, Vol 8, January, 1971.
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As shown, it is predicted that the overburden could be removed using scrapers
I only (or pushed by dozers) from the surface to a depth of about 5m, with some
bands requiring ripping, and it could be removed using scrapers after dozer
ripping from about 5m to about 10 to 15m. Below 10 to 15m, the rocks will
I require blasting.
While the data shown on Figures 6, 7 and 8 may not in fact relate closely to
actual excavation practice, i.e. the level at which the rocks require ripping
I or blasting may be higher or lower than shown, Figures 6, 7 and 8 and the
logs do allow an assessment of how the excavation characteristics might vary
I across the site. In general, there appears to be no trend of variation in
thickness of weathered material in any specific direction, i.e. while there
may be occasional areas where the degree of surface weathering is markedly
I different from the general condition, on the whole, the extent of surface
weathering is reasonably consistent over the site.
I The fact that the initial small scale mining operation will be performed under
I contract, where it will be the contractor's task to experiment with various
combinations of excavation equipment to produce the most efficient method
I of overburden removal in each weathering horizon, will be an advantage.
This will allow R W Miller & Co to use this experience in combination with
I the data presented herein, to produce the most efficient means of overburden
removal.
11.0 CONCLUSIONS AND RECOMMENDATIONS
11.1 Highwall Stability - Western Zone
The likelihood of stability problems with highwalls in the western zone
should be less than for those in the eastern zone, assuming similar slope
geometry. The geotechnical properties of the strata are similar but the
maximum highwall heights will be significantly lower. At this stage, however,
we would recommend adoption of the same highwall geometry for the western
zone as for the eastern zone. (Refer to Dames & Moore report on Highwall
Stability.)
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11.2 Lowwall Stability - Eastern Zone
It is understood that maximum overall slopes of 360 are planned for the lowwall,
I with a benched profile as shown on Figure 3. It is also assumed, however,
that in the lower portions of the lowwall, where the dip of the seam flattens,
I the slope of the lowwall would be reduced accordingly to conform with the
slope of the seam. The dip of the seam increases from about 340
in the south
to about 510
in the north.
I Due to the general competence of the overburden rocks, we feel that a lowwall
formed at a maximum overall slope of 360 in the upper portions and flattening
nearer to base where the seam flattens, with a benched profile as in Figure 3,
would have good overall stability.
The possibility exists for isolated failures of individual benches where
I the dip of the strata is high and occasional weak bands occur. This is more
likely to occur in the northern part of the site where the dip of the strata
I is greatest. However, most such failures should occur upon blasting and
excavation. We consider the possibility of extensive bench failures in service
I to be low. Should, however, it be considered necessary to completely
eliminate the possibility of bench failures, consideration could be given
I to stacking benches excavated at the bedding angle or lower, say up to three
feet high, so that undercutting of bedding is avoided.
The procedure which would result in minimum excavation of material beneath
I the seam would be to form the lowwall at the same overall slope as that of
the seam, over the full height of the lowwall. This would mean a steepening
of the slope beyond 360 for the upper portion of the lowwall in the northern
I part of the site, to a maximum of about 500. on the basis of the data
presently available, it is not possible to assess the effect such steepening
I would have on overall stability of the lowwall.
I We recommend that for present planning purposes, the overall slope of the
lowwall be designed for a maximum slope of 360. Should the economic
I advantage of steepening the lowwall in the northern part of the site be
considered to warrant further investigation, this could be done during the
detailed design stage.
Li
- 17 -
Li
11.3 Lowwall Stability - Western Zone
Due to the absence of faulting in the vicinity of the lowwall in the western
I zone, design of the lowwall does not warrant the detailed consideration
required in the eastern zone. For preliminary design purposes, we would
I recommend adoption of a benched profile of overall slope 360 as shown on
Figure 3.
1 11.4 Spoil Stability
I Spoilpiles developed in accordance with the geometry shown on Figure 4 should
experience no major stability problems. Failures could occur in areas where
I the material forming.the floor of the pit is weak. Care should be taken to
identify such areas upon exposure by coal removal, and remedial measures taken.
I Such measures could consist of the following: Where the weak zones are
relatively isolated, the weak material should be removed and disposed of
with the overburden. Where the weak areas are extensive such that their
I removal would be too costly an exercise, trenches could be excavated through
to more compenent material parallel to the toe of the spoil. This would
I effectively "key" to toe of the spoil into the floor of the pit. Typically,
these trenches would be about 25m wide at lOOm spacing.
Continuous grading of the upper surface of the spoilpiles should be performed
toavoid ponding of rain water and thereby minimising the possibility of
saturation of the spoil with subsequent reduction in stability.
11.5 Groundwater Inf lows
I As mentioned in section 9.2, our field investigation program was aimed at
estimating the order of magnitude of groundwater inflows into the pit, rather
I than attempting detailed flow predictions. We estimate that during the first
two to three years of operation of the pit, flow from both seams of the order
of 300,000 litres per day can be expected for pit dimensions of 1500m long by
30m wide at the base. The flow, from the Glen Munro/Woodlands Hill seam should
constitute about one third of this total flow.
I L I
-18-
I
We suggest that the rate of groundwater flow into the pit during the initial
I contract mining operation be monitored to allow a more accurate prediction of
longer term flow rates. Based on the limited data available to date, we would
I estimate that the rate of flow to be expected from the Piercefield seam would
that in the Glen Munro/Woodlands Hill Seam. be about 200 encountered
11.6 Overburden Excavation
I Our investigation indicates that generally the overburden from the surface to a
depth of about 5m could be removed using scrapers and dozers, with some bands
I requiring ripping; the rock between 5m and 10 to 15m below the surface should
require extensive ripping while the rocks below lOin to 15m will require
blasting.
Again, the initial contractmining operation should be closely monitored and
I this data, along with the strength and fracture frequency data shown on the
geotechnical logs, be used to predict excavation characteristics in other parts
I of the site.
I I I I I I I I I I
- 19 -
LIST OF FIGURES
Figure No
1 Site Plan
2 Pit Schematic
3 Sections AA t , BB 1 , CC' - Lines of Boreholes 24, 28, 32
Showing Approximate Lowwall Profiles
4 Typical Highwall and Spoilpile Geometry
5 Properties of Rock Underlying Piercefield Seam
6 Groundwater Levels and Rainfall Data
7,8,9,10 stratigraphic Sections - Lines 24, 28, 32
S :
/
( (Li (
17- 052?
300 3b0000
WESTERN ZONE 30000
IE
0000
I I I I I I I I I I I I I I I I I I I I
1388150
1386000
10 Z25 8025
C) 025
1307000
8
c onFFU o
028 C20
V
A20 7C20
I /7
/
000300 8302 C30 DD
20
31 flO OSHO 1386000
:f 0633
0 0
00002 832 CC32 0
000 L
033 0033
I 0 I I - ho85300
39000 L 330000 310950
EASTERN ZONE
REF., R.W MILLER DRG. - PLAN 2 SITE PLAN DATED 17/ 10/77
SCALE a oon. 0 200 400 600 800 1000m
FIGURE I
LEGEND
WAMBO— Inferred Outcrop of Seam
$8828 Location of borehole
50m contour
I I I PIT SCHEMATIC
D1ES B MaOnrz
FIGURE 2
REF REPORT; "Preliminary Study for Cool Mining Operations at Mt Thorley"
by Kinnoird Hill de Rohan a Young Pty Ltd. doted Oct, 1977, Fig. I
I I I I I I I I I I I I I I I I I
01-i 12 OHi2M 01-1121 0H12i
- SURFACE - -
'- BENCHED LOW WALL OVERALL SLOPE 34° iO
70° -O
_b I_ --20
-40
-50
-60
OH 20H OH 20M OH2OK OH2OL
0
70
50
4°
30
20
F- 0
L
-20
-30
-50
--60
--70
-80
L 9
OH4G OH:4H 0H41 OH4J
BENCHED LOW WALL OVERALL SLOPE 34°
I I I I I I I I I I I I I I I I I I I I
R(.
60
50-
40
30-
20
iO 1 0-1 OH
20 H
° H - 40
-50
60
R.L 80,
70
60
50
40 -i
30 H 20 -I
0 -
oH
-10
-20
-301
-40
50 H
-60
-7° H
-80
- 90 -
R.L. 70
60
50 -
401
30 -
20
iO-
oH - 10 -
- 20-
- 30-
- 40
- 50 -
- 60-
- 70-
- 80-
- 90-
BB24
plER0 SEAM
INN - SECTION A-
BB8 CC28
SECTION B -B' LINE 28
BB32 CC32
P1
SECTION CC* LINE 32
NOTE
The lines of boreholes ore not per pendiculor to the strike of the strata As a result the dips of the seams shown are apparent dips and the slope of the low wall as shown is less than its maximum slope The true dip of the seams along lines 24,28 and 32 are 51°.42°and 340 respectively and the irue overall low wall slope is 36°.
NOTE See Fig. I for locations of sect ions
R.L. 70
SCALE I 1000
40
60
50
F I_30
F 20
tO
CROSS - SECTIONS h20 AABBCC1 — LINES -30 OF BOREHOLES 24,
Ho 28,32, SHOWING ° APPROXIMATE
b60 LOW WALL PROFILES 70
B --90 t(lIP
38° OVERALL SLOPE 360
HIGH WALL
_-.- R --OVERALL SLOPE 26 0
TYPICAL HIGHWALL AND SPOILPILE GEOMETRY
Kit
SCALE: 1:2000 DSBP.00flE
FIGURE 4
I I I I I I I I I I I I I I I I I I I I
PROPERTIES OF ROCK UNDERLYING PIERCEFIELD SEAN
Borehole Depth Rock Type *Estirnated Slake Compressive Durability
No (m) Strength Classification Classification
X26 116.85 Interlaminated fine low-medium sandstone and siltstone with carbonaceous bands
Z24 137.84 Carbonaceous Mudstone low medium high
Z28 180.55 Interlaminated sand- stone and siltstone medium medium high
Z32 168.32 Interlaminated sand- stone and siltstone medium-high medium
AA28 151.86 Interlaminated sand- stone and siltstone medium
AA32 163.95 Interlaminated fine sandstone and siltstone medium
BB24 124.35 Claystone extremely low low**
- very low
BB27 149.79 Interlaminated sand- stone and siltstone medium
BB28 160.14 Interlaminated sand- stone and siltstone medium-high high
BB29 162.35 Fine to medium sand- stone with siltstone medium
BB30 158.55 Interlaminated sand- stone and siltstone medium
B332 148.57 Claystone very low low**
CC32 129.02 Sandstone low-medium
* Point Load Strength tests on these samples at natural moisture content not possible since core removed from site with coal, core for coal analysis.
** Core samples too weak for sensible testing - low slake durability classificatio3 based on weak condition of core.
Figure 5
TABLE OF GROUNDWATER LEVELS
Depth from Surface to Groundwater Table (in)
Borehole Date of Measurement (All 1977)
No. 6 July 7 July 8 July 15 July 10 Aug 2 Nov 21 Dec 2i jiec
AA31 7.0 - - 8.0 9.7 9.8 -
- 15.2 - - 14.5 13.3 13.4 - BB24
BB28 14.6 - - 13.2 15.3 14.8 - - 4.9
BB32 - - - - - - - 22.0 21.4 21.6 -
X24 - - - X28 16.1 - - 31.5 31.0 30.9 31.0 -
X32 18.5 - - - 18.0 17.8 17.9 -
- - 18.5 - 16.0 14.6 15.2 - Z28 - 12.0 L24 - - - - - - - GWL@ L32 - - - - - - Surf ace*
flowing out of hole at rate of 100 c.c per minute. * Water
TABLE OF RAINFALL DATA*
Monthly Totals (mm) for 1977
June July August September October November
15 4 17 48 8 16
** Rainfall data for Jerrys Plains from the Weather Bureau
Figure 6
SOIL & SUBSOIL.
I uu_j A/I.A I
COAL. AGGLOMERATE
COAL & BANDS INTERCALATED.
CARBONACEOUS SHALE.
SHALE - NOT CARBONACEOUS.
COAL TYPE
SHALE & COAL EANDS. WHEN RECORDED
DULL
ULL BANDE
SHALE - CARBONACEOUS N PAPJ. ULL & RIGHT
LBRIGHT BANDED
SHALE & SANDSTONE.
.. . : -:1 GRIT & PEBBLES SANDSTONE TYPE
' f FINE :?4 1FINE TO
0 CONGLOMERATE. MEDIUM
e • MED1UM
• MEDIUM TO COARSE
CLAYSTONE & MUDSTONE. COARSE
CLAYSHALE. Ii/l SANDSTONE & SHALE
_- -=
:--1 SILTSTONE. SANDSTONE & COAL BAND
A A A A] E1 TUFEF=AA-
CLAYSTONE-?TUFFACEOUS
A AA A A
A—
B Note for mixed lithologies e.g. fine sandstone
AA] sitty in part a tIne boundIng the sandston symbot indicates fine sandstone is domincnt
IGNEOUS ROCKS.- otherwi5e fine sandstone overprints the DOLERITE. sittstone but no bounding tine is drc.vn.
sndstone CHERT
or°st
sittstore
- - . sandstone
) ' . COAL CINDERED. No mckIhc Lusr€ & Cok-Iik. .: I Lost SOO/o ktrs'vblatiSe of ,(: Cont,nt i stIi a
CommercaI Pot.gtt,aI as a futt
COAL CINDERED. Ash-Iskt. no comorcot Potvtial as a FtI.
MATERIAL FROM 0.0 TO 4.5m : EXCAVATABLE BY SCRAPERS 4.5m
MATERIAL FROM 4.5 TO 9.Om EXCAVATABLE BY RIPPING 9. Om
I I I I I I I I I I I I I I I I I I
_jpm GROUND WATER TA3 L E
DEGREES OF
EXCAVATABILITY
(DEPTHS)
I
LEGEND- GRAPHIC LOGS
I REF.: JCB PLAN No. EC 507A FIGURE 7
70.
X2L
)/,
I
WEST
EAST R DD
lOOm
Z2
4424
I,
os,, ,.10
370,, 660,,
605,,
os,,
7,.0,, 360,,
660,,
-
li
50.
NOTE SEE FIGURE 7 FOR LEGEND
REF JCB PLAN No. Al-C206 doted 24.3.77.
,6,7'N7A. '. Aol 6N.,I'Fof vIA' A OCAIF IN 6.16166
100 50 0 100 10 5 0 10
STRATIGRIPHIC SECTIONS LINE 24
DAMES & MOOR* FIGURE 8
WEST EAST R DD
Z2t
80n, -1
I AA 28
9H 28 iE4 : -1--
SO
4.=
8.
7001
6001 •
TOrn , :1
400,
30nr 49.460rn
2010
On, -
.14 IOO. - 7lrrn
I.. - o.
J. 91615., 91 91-
- 101 45Cm - 20,1
III
104 030,, - 1(15 50(1 ISO 405,,
SIdo.,Ie
SOrn
60.
! it 11 ,, .'. 151 550m I5t. 27511
-801,1
i
- -
- 90 00
UDH1 STRATIGRAPHIC -10001 DDH - SECTIONS
LINE 28 NOTE SEE FIGURE 7 FOR LEGEND REF JCB PLAN No. AI-C206 doted 7.6.77 HOLE ' TERMINATED - 1100, AT 317.415m @9
00,1005141 SCAlE IN METRES
100 50 0 100
. i,I4( 0, A, ,', M'WI
10 5 0 10 . - O•B B moomm FIGURE 9
I I I LI I LI I P H
H
P
I I LI I I I I I I I
A32
IOn
S
-2On
-3O
PW
AOn,
NOTE SEE FIGURE 7 FOR LEGEND
REF .JCB PLAN No. At-C206 dated 17.3.77
100 50 0 100
I I I I I I I I I I I I I I I I I I I I 10 5 0 10
WEST R
Z 32
EAST
DD
R.L. 65 460ns.
ACEREDUCED EL 62.57559 L OF 6832 SURFACE REDUCED ISITIONED TO
J LEVEL OF CC 32 55 460n,.
•- 1
POI.IoD TO 5 62.575m.
7?11P90
STRTIGRAPHIC SECTIONS LINE 32
DAMB & MOORE FIGURE 10
I -20-
I APPENDIX
FIELD INVESTIGATION AND LABORATORY TESTING
For details of the field exploration and laboratory testing performed are as
covered in the appendix of our report "Geotechnical Investigation, Highwall
Stability, Proposed Surface Coal Mine, Mt. Thorley, N.S.W.", submitted on
14 November, 1977.
The items covered in that appendix are as follows:
Field Exploration: Core logging
Installation of Standpipes
Point Load Testing
Laboratory Testing: Moisture and Density Determinations
tjniaxial Compressive Strength Testing
Direct Shear Strength Tests
Direct Shear Tests on Joints
This data will not be repeated in this report; this Appendix, however r, presents
the details of the borehole pump-out test program.
Field Work: Borehole Pump-out Tests
Pump-out tests were performed in boreholes BB28, BB30 and BB32 to determine the
transmissivities of the Glen Munro/Woodland Hills seam and the Piercefield seam,
which allowed an estimation of the rate of flow of groundwater into the pit.
Borehole BB32 was tested on September 23, BB30 on November 4, and BB28 on
November 9, 1977. Pump-out test results from BB30 and BB32 provided estimates
of pit inflow rates from the Glen Munro/WoodlandS Hill seam and test results from
BB28 provided estimates of pit inf low rates from both the Glen Munro/WoodlandS
Hill and piercefield seams.
I The transmissivity (T) of a water bearing formation is dependent on its thick-
ness and its permeability. In computing T from the pumping tests, it is assumed
that the Glen Munro/Woodlands Hill and Piercefield seams have a reasonably
I uniform permeability and that the enclosing rock layers are relatively impermeable.
I
- 21 -
The best way to determine T is from water level recovery data following pump
shut-off after a period of eight hours during which a stable pumping rate has
been maintained.
The time-drawndown measurements during the pumping period and the time-recovery
measurements during the recovery period provide two distinct sets of information
for a test from which the residual drawndown curve is plotted and used to
determine the value of transmissivity (gallons per day per foot) for the seam
(or seams) in the particular borehole tested.
Method of Testing
In borehole BB32, a Prosser submersible 71-2 HP electrical turbine pump (rated
at 120 gallons/mm) with 75mm diameter PVC evacuation pipe were used. In
boreholes BB28 and BB30, a Grundfos electricsubmersible pump, model SP10/18,
5 HP, 3 phase motor was used instead. In both cases, a 20kVA, 3 phase generator
was used to drive the pumps.
In each test, the pump was lowered down the 280mm dia. borehole and suspended
with a cable at the required levels of depth below the top of each hole for the
entire test. PVC standpipes, 43mm in diameter and perforated at the bottom
3 metres of its length were installed in each pump hole down to the level of
the pump. An electrical water level measuring probe was used to measure the
water levels in these standpipes during the drawdown and recovery stages of
the tests. The purpose of operating the electrical water level measuring
probesin the standpipes was to eliminate possible misreading of the probe due
to cascading water from above.
In boreholes BB28 and BB32, no observation wells were available. In borehole
B330, 2 observation wells (BB30/1 and BB30/2) were available and their positions
Iwith respect to the pump hole BB30 were as shown below.
Pump Hole
Observation Wells N
BB30 BB30/2 BB30/1 ____
4.6rn
12.2m
- 22 -
PVC standpipes were installed in these observation wells as in the case for
the pump holes. The water level recovery data from these wells fully reflects
the hydraulic characteristics of the coal seams.
During the pumping period, pumping was maintained at a constant rate by measuring
the rate of water discharged from the outlet. The outflow was controlled
by regulating the outlet control valve to obtain the required pumping rate.
On commencement of each test, time-drawdown measurements were recorded for the
pumping period, which averaged eight hours for each of the three pump tests.
When the pump was switched off, time-recovery measurements were recorded. The
actual recovery in the water level - the distance that the water rises after
pumping ceases - was expressed with reference to the pumping water level. These
recordings yielded the residual drawdown curves (as shown in Figures A15-A17),
required for the determination of T, the transmissivity of the coal seam.
Test Results
Test 1
Borehole: BB32 Date: 23 September 1977
Depth to bottom of borehole = 23.5m
Depth to top of Glen Munro/Woodlands Hill seam = 18.Om
Thickness of seam = 8m
Static groundwater level at 4.Om
Pumping level at 22m
Pumping period = 3½ hours
Average pumping rate = 9 gallons per minute
Transmissivity, T = 43.9 gallons per day per foot (refer residual drawdown curve,
Figure A15).
Test 2
Borehole: BB30 Date: 4 November 1977
Depth to bottom of borehole = 35.5m
Depth to top of Glen Munro/Woodlands Hill seam = 26.47m
Thickness of seam = 7.93m
Static groundwater level at 1l.85m
Pumping level at 26.0m
I -23-
I Test 2 (continUed)
Average pumping rate = 8.95 gallons per minute
IPumping period = 73a hours TransmiSSiVitY, T = 70.6 gallons per day per foot (refer residual drawdown
I
curve Figure A16a).
Observation Well: BB30/1
I Location: 12.2m to east of BB30
Depth of bottom of borehole = 38.5m
Depth to top of Glen Munro/WoOdlands Hill seam = 26.Om
IThickness of seam = 8.5m
Static groundwater level at 11.29m
Depth of water level immediately before switching pump off in BB30 = 13.77m
TransmiSsiVitY, T = 306 gallons per day per foot (refer residual drawdown curve
Figure Al6b)
I
Observation Well: BB30/2
I Location 4.6m east of BB30
Depth to bottom of borehole = 38.5m
Depth to top of Glen Munro/Woodlaflds Hill seam = 25.5m
Thickness of seam = 8.5m
Static groundwater level at 11.94m
I
Depth of water level immediately before switching pump off in BB30 = 14.50m
TransmissiVitY = 300 gallons per day per foot (refer residual drawdown curve
I
Figure A16c).
I I
Borehole: BB28 Date: 9 November 1977
Depth to bottom of borehole = 160.99m
I Depth to top of Glen Munro/WOOdlands Hill seam = 22.9m
Thickness of seam =8.49m
Depth to top of piercefield seam = 141.49m
I U
I I I I I I I I I I I I I I I I I I I I
- 24 -
Test 3 (continued)
Thickness of seam = 17.84
Static groundwater level at 14.82m
Pumping level at 33.Om
Average pumping rate = 15 gallons per minute
Pumping period = 12 hours
Transinissivity, T = 132.6 gallons per day per foot (refer residual drawown
curve Figure A17).
- 25 -
LIST OF APPENDIX FIGURES
Figure No. Title
Ala Explanatory Notes - Engineering Log -
Cored Borehole
Aib Key to Engineering Logs - Cored Boreholes
A2 - A14 Engineering Logs - Cored Boreholes
A15-A17 Residual Drawdown Curves for pump-out tests
A18, A19 Results of Slake Durability Tests
A20, A21 Estimates of pit inflow rates for pump-out
tests in boreholes BB28, BB33 and BB32
I I I I I I I I I I I I I I I I I I I I
EXPLANAtORY NOtES: ENGINEERING LOG CORED BOREhOLE
DESCRIPTION OF CORE
All rock types and stratification spacings have been classified according to definitions below (from: McMahon, Douglas & Burgess - Engineering classification of sedimentary rocks in the Sydney Basin", Australian Genmechanics Journal Vol.G5, No 1, 1975, pp5l-53).
ROCK TYPE DEFINITIONS
ROCK TYPE DEFINITION
Conglomerate More than 50T of the rock consists of gravel sized (greater than 2mm) fragments. Sandstone More than SOS' of the rock consists of sand sized (.06 to 2mm) grains. Siltstone More than 5O of the rock consists of silt-sized (less than .06mm) granular particles and the rock is not laminated. Claystone More than 505 of the rock consists of clay or sericitic material and the rock is not laminated. Shale More than 50 of the rock consists of silt or clay sized particles and the rock is laminated.
STRATIFICATION SPACING
TERW SEPARATION OF STRATIFICATION PLANES
Thinly lam i na tech <60 Laminated 6mm to 20mm Very thinly bedded 20mm to 60mm Thinly bedded 60mm to 0.2m Medium bedded 0.2m to 0.61T) Thickly bedded 0.6m to 2m Very thickly bedded >2m
WEATHERING
Degree of weathering is represented in histogram form which indicates the general trend of weathe'- ing. Bands of significantly smorehighly weathered material are noted in 'Description of Core'. Definitions of degree at weathering used throughout are:-
DEG.gEE OF WEATHER I MG
APBPFVIATI°°4 - DEFINITION
Fresh Fr The rock shows no discolouration, loss of strength or any other effect due to weathering.
Slightly SW The rock is slightly discoloured, but not noticeably lower in strength than fresh rock.
Weathered
Moderately MW The rock is discoloured and noticeably weakened, but 100mm diameter drill cores cannot usually
Weathered be broken up by hand, across the rock fabric.
Highly NW The rock is usually discoloured and weakened to such an extent that 100mm diameter drill cores
Weathered (wet) can be broken across the rock fabric readily by hand. Wet strength usually much lower than dry strength.
Extremely EW The rock is discoloured and is entirely changed to soil but the original fabric of the rock is
Wea the red mostly preserved. The properties of the soil depend upon the composition and structure of the parent rock.
DEFECTS
All dips are measured from a plane perpendicular to the axis of the core. Joints are indicated graphically at appropriate RL and dip and are described in 'Description of Defects". Other defects e.g. bedding partings and fracture zones, are indicated by short horizontal lines along the left side of 'Description of Defects column. Individual bedding partings are generally not described; hence, defects indicated should be assumed to be bedding partings unless described otherwise.
DEFECT_SPACING
Defect spacing is represented in histogram foram. Spacing has been calculated for zones through which the spacing of natural defects is shmul lar.
POINT LOAD TEST DATA
Strengths plotted are those measured perpendicular to bedding converted to Is(SO)values (Ref: Broch & Franklin The Point Load Strength Test"-Int.,J.P.ock Mach - Min.Sci. Vol .9,pp669-697)
STRENGTH CLASSIFICATIONS
Extremely Very ow Low Medium High Very High Extremely
EL M H VII EN
Strength Classiricatiorm
Abbreviation
0.3 3 10
Anisotropy indices calculated where tests done at 90° and 0° to bedding. Where strength parallel to bedding is greater than strength perpendicular to bedding, anisotropy index is asterisked. lihere more than one anisotropy index can be calculated for a earticular secti on ( j . e. more than one test done in either/or both directions) both values are recorded if ratio is greater than 1.25 but are averaged if less than 1.25.
a FIGURE Ala
I I I I I I I I I I I I I I I I I I I I
KEY TO ENGINEERING LOGS - COBED BOBEHOLES
Sandstone: grain size indicated on description of core
Conglorrrate
Siltstone
Mudstone
Carbonaceous Carbonaceous traces and
Mudstone coal wisps indicated by:-
Siderite band
Clays tone
Coal
NERAL NOTE: Legend used was according to "Graphic Representation of Coal Seams' /\ust Standard K183 - 1970, 8 pp. with the exception that coal types were not differentiated.
All coal scams were blacked out.
See attached sheets.
FIGUBE ATh
ENGINEERING LOG - CORED BOREHOLE BOREHOLE NO.: L 24 Sheet / of 6
Borehole location: R. L. Surface: 92571n Grid coordinates: Job No. : /023 - 00/ - 70
N. /3877555.9 Client : R. MIsLE 4'! Co PTY LTL) E: 30452s 85 Datum: A - I-i. b. Project : MT 7 /oRy, LE,tsE
Location : .S/NLEroN, A/sw Borehole inclination Borehole direction: 0° (From horizontal):
Hole commenced Drill type : REFER R. W. Log describes all strata recovered El Hole completed . Mounted on RECORLS including soil over rock.
Supervised by Drilling fluid
Log checked by : Barrel type : For log of strata over rock see Engineering Log - Borehole
POINT LOAD
Z . TESTDATA
DESCRIPTION OF cr E
DESCRIPTION > Cl) Ir I-
DZO 2 DRILLING
CORE I OF <E cc
o DATA&
DEFECTS u:t 00— COMMENTS
2 10 50 200
0 1 5 1201,005
2 -
4-
1;
8
>-
cE3 /0-
/2 -
SANbSTONC: f/ne /*3/)/q fractured sand mat- ' 14
1,3
SAin.s TONe 5/Ts70c1s. thfer/aminatczd and 4?f&rb&a'rJ,2d
1 *
5ANDST0NC: pale ?rg. 5rti:r?a'. modena/e& hard, ifepbedded -.---: I
Muds/t,rje baid ai óase
-1--- COA4 S5.4M.' 2. maf WHYBROW 54M 7'h/k /c1i7'/7 /h7'arca/a?417s ,,f Szd,men/s 24"/a 9'searn 6 dtb, 5at7a'S 0 4550
L aysc 5a,?d: a. /85m - FR --- - SW
HW
MW FIGURE A2 EW-
I
I
I
I n u
I I I I I I I I I I I I I i-i I
ENGINEERING LOG - CORED BOREHOLE BOREHOLE NO.: L24 Sheet 2 of S Borehole location: R. L. Surfacer Grid coordinates: Job No. : /023, - 00/ 70
N: Client : R. W. /LR Co P7)' L77) E: Datum: Project : MY, 7-H0L6 y 1_EAE,E
Location : 5INc*1E7-oAi, N Ltl Borehole inclination Borehole direction: (From horizontal):
Hole commenced : Drill type : RIE FER e W. /VIILL.ER i-i Log describes all Strata recovered
Hole completed : Mounted on : L_..J including soil over rock.
Supervised by : Drilling fluid
Log checked by : Barrel type : For log of strata over rock see Engineering Log - Borehole
POINT LOAD o . TESTDATA
DESCRIPTION OF rr DESCRIPTION DRILLING
CORE I- i OF <E g DATA&
W Lii 0 DEFECTS COMMENTS
(9 U)
2 10 50 200 U) -
2 0100500 1 5 1201,001510 Of
AJ Only dimnfs jr&zter i'/?an 1 - 0. / iz 1h/c1(n.S'8 shown.
. SANASTONE pa/5vri.j, /? 9ra(n2d, Thodrcle(y /7ara', 7 -/in/q lo/'r5dc/d o.nd /cfr/or77/nCtea
Madstcn £5cn0(s ct op a,'o' :
bo/±orn, moderately so/I 710 ½arS 1/7
24- COAL SAA.' I. iç 'r,tr thth w/s½ /Qhzrca/a I-ions 01e &2d;(r2n/-s -
/ SQ7T) 1
2,2 CLY57b,iE . greyi-th lb t€ly sano(j lbx/zjra In ,oarf,s Z
MU1,s TONE: grec modsnilb(q &
2.0 SILTSTOA/E: q,-ay, moderafafg
2 -. 4AJ0ToNE.' grey 2rne yrainc10 hard.
III
30-,'
grades ,ri€c//an) lb coarse yaiQed -. .
Ccng/omr,.-te prWes /0mm s.
32 - b- -
(Pades 71117e lb med/am, Sandstone modepai/, Mapo'
':. 7' l)fchIy //7terea'ded. 4 r,c/es of 2.2
/1ining wpwards 00riq/omer(9 /a r5c7nas to 0/20m
36
14
MusTo,ig: larkgrej lb grey,
moderalbi sa/ /am;nai.d .8
SANOSTONE: Pa/a gr mad/em 5pa;ned, moa'erate/' ---------- hard.
ri-I i
SW
II MWJI HW I FIGURE A3 EW
I I I Li I I n n H
n
I I I I I I I I I I
2.8
2.5
52-
- ;7;,7-t, clips o°, rnagh, irregular con7',naozJs at
4. top and hot/am.
54-
1.2
5
2.8
BOREHOLE NO.: £24 Sheet of 5
JobNo. : 1023E.-00(- 70
Client : R. W. A'IILLER 4 Co Pro' I713.
Project : MT. 7H0EL5v LEASE
Location : 6lNc1E 7bN, A/SW
Eli Log describes all strata recovered
including soil over rock.
11.1 For log of strata over rock see Engineering Log - Borehole
POINT LOAD
> . TEST DATA
- cc
m I- E- UJif ,. DRILLING
z
CL
DATA&
-
W
rn—lao- ox
COMMENTS z
10 50 200 1 I 5 Izo 1100150 I I -
3.5
DESCRIPTION
OF
DEFECTS
w i
I— - 0- 51: Lu Ui 0
(9
ENGINEERJNG LOG - CORED BOREHOLE
I Borehole location: R. L. Surface: Grid coordinates:
N:
Datum:
I
E:
Borehole inclination Borehole direction: (From horizontal):
Hole commenced : Drill type : REFER R. . M/LLER Hole completed : Mounted on :
U Supervised by : Drilling fluid
Log checked by : Barrel type
I DESCRIPTION OF
CORE
I (Corn'...) .çANL3STONE:
I I I I I I I I I I I
A4UI3STONE $ &4NhST0NE:
lot
Mar/stone : qreg to darl<'yi'ey. tnoderatey sL'( 7'O rnoderafe(j hand.
Sond.s/ofl: gPe/ 7'Opa/e gnr, //na qrained. Car/nac5ou5 mip base
4L SE'v'4.' 0• 5 mztr,z thioë AIUDSTOIVE qvaq to dark noderatef!/ SOj /t' mod. hard.
AN86TOA1E pa/s 9Veq ,/i4s' gr~s/ned.
,(4/JA~ TONE . cm7r6oflao al a.se
CL'1YS7bNE.; g/'egI.th whh'e
M11L3STON . carboriqcec, 9r1, moderate/s, hard ecal
hands t, 80 mm._—__________
CLe >'.STONE gr'ej/sh whi/,
mocJapa/e/1 o1C7
7FITAi5 TO AlE or , Thocirna/zi Carôonaczous a baz
COAL SEAM! 0.24 mec -frh/ak MuOsro,vE gory Ic' dan/c gray
S1/Vos TONE 5/L7ToNE inter laminated So/Eo M(JLt~Tof16: moderately &,'t ~
d4,teg hard. SAl/AS TONE .S/1-7-570'VS: /nler/ami',rr,4d and intanjbrdd&J,
.9I1 ( ,pid tjM.ed.
SAvL STONE: 1'5g, grainad
AIOSTONE 4 SILTS TONE;
Inter/am/na/ed 6 interh,zddd, 5/5o
SAA1b5TONE:
"sy to pa/s yns.y
/2fA to mEd/c/fl7
o7odenate/d hard, y io3addcd.
FR
SW
MW HW EW
42
44.
1.'
ENGINEERING LOG-CORED BOREHOLE BOREHOLE NO,: L24 Sheet 4 of 5
Borehole location: R. L. Surface Grid coordinates: Job No. : I020 - 001 - '70
N: Client R W. MILLER 0 6 PTY iTD. Datum: Project : MT rHoitY 1-EAEE
Location : SfiIOi..E TON NS W Borehole inclination Borehole direction: - (From horizontal):
Hole commenced Drill type : RFE Log describes all strata recovered
Hole completed : Mounted on : RECOROS L_J including soil over rock.
Supervised by Drilling fluid
Log checked by Barrel type : For log of strata over rock see Engineering Log - Borehole
POINT LOAD 0 (3 TESTDATA
DESCRIPTION OF - DESCRIPTION
07, DRILLING
CORE i - OF <E DATA&
DEFECTS 1L 7 00— COMMENTS
(3 2 10 50 250 (15
60 5 20 100 50Q ar <
-rn (Cout ) SANIDSTONE
Car'boaceou6 a//S,O
.......
CoNLo,t-iERArE /usIgi] pe6b/s 1?) 3.Emm. S3e ifS 7 ' 0 Q. 1 .2 Sands m as n/J<'.
64 SANLT01vE. paie7rey. fflEc/itim -
¶aInec/ mOde(Qfe/y hard7
- 6.6 SILYS TONE re to dark
mociet-ri-le/g hard
- ANToNE: pale goe
,77'7diam ±0 coor6e 19cm1'ned, moclei'aS'e/y hara lhiCk& /f7tePbrJcld I
I
-77
?nadzs 74ne sLo med am gmineo' 76
C0NLL0/46RATE pale ló/W5/5 5're, j, pc/ymicf , oeAbles 7's 4oleas .
l in Sand1 rroafrix. Q Sider,te band a! base
7
—,
COAL SEAM. 0. E25 ,17'7friES -IhicJ(.
LB SANbsTONC: pa/c qr, firse .:
grairsed, rnoderatc/7hacJ.
MJô,sroNE moaloi,, 4' SANST0N,e~:
'0e graThed, modafc( hatd. 74
SANcOSTONE S/Lrs701\1 frifr/aminafcd d interbdcicd
7, SANOS TONE pate grøy mdam
gralrsed, shnI5 S4j 7'l'tiCk/y 4 infer,ócc/ded Coarsc and/line yc/e wth' Car/sonaccoas wisp.s.
76 '1.
FR-' Ifl SW --- I MW--Th HW
FIGURE 1A5 EW
I I I I I d I I I I I r
li
P
I U
I I I I El
11M A&M MS B PIOOE
ENGINEERING LOG - CORED BOREHOLE BOREHOLE NO.: 424 Sheet of 6-
Borehole location: A. L. Surface: Grid coordinates: Job No. : /026 - 001 70
N: Client : R.W. MILLER Co TY L70 E: Datum: Project : MT. ThoRI.ay /LEASE
Location : SINc1.67oN NS IV. Borehole inclination Borehole direction: (From horizontal):
Hole commenced : Drill type : R. w. MILLR Log describes all strata recovered
Hole completed : Mounted on : bRiLL/u RgcaRs LJ including soil over rock.
Supervised by : Drilling fluid
Log checked by : Barrel type : For log of strata over rock see Engineering Log - Borehole
POINT LOAD
z 0 0 TESTDATA
DESCRIPTION OF . DESCRIPTION >- I Lu DRILLING
CORE I F- OF <E DATA&
w LU DEFECTS
(/5 Ut _t' 00— COMMENTS
0 2 10 50 200 I- CO co
1 15 20 0050
(c-t ) SAAIOSTO/VP -
82-
Grodos to ine 5ra,nd mociarafEy hard, infor5ecIad 84 wi*? minor SiMs/bne
!1(L/OSTO/vE ry 7,0 dark modera/-aIy so/Y 7 modoTa/a/y 85- hard
. = COAL SEAM: 0.5/6-m ItoL/C. WAMO SEAM /fgTONE COAL 5,w: /.660 natra
MuTsTov: modsratoly off to rnoc/arate/g hard.
2 AA/0STo/'IE mac/IL/rn 5rained
MuOST0,vE: graj 7'0 dark gre',
morto/,, Soft i-c mcc/aratof5 hard.
S4-
SANyoN5 : f2Th5 511/ned
MuisToNea: qraj to c/ark gr&q, IodvLa/i 50(t' to moderata& hard, carbonacgc in parts.
ILTSTOA/E-' gPacj, modamtefy hard, sirJrif& banae,
too SicrS TONE : moderataL,, hard,
FR liii I ISW
MW—UI FIGURE 446 EW
I I I
I I I n
H H I I H I I I I I H
I FIGURE ,A7
ENGINEERING LOG - CORED BOREHOLE BOREHOLE NO.: L32 Sheet / of 5
Borehole location: R. L. Surface: 62. 8(5 in Grid coordinates: Job No. : /02&, - 00/ - 70
N: /35785 63 Client : R.vi. MILE R t' Co PTh' L7D E: 304600. 47 Datum: A. H. t'. Project : MT THoLy LEASE
Location : Su-iQLETON NSIA/ Borehole inclination Borehole direction: 30 (From horizontal):
Hole commenced : Drill type : REFER ,Q.t./ Log describes all strata recovered
Hole completed : Mounted on : RfLL/N RORAS L_J including soil over rock.
Supervised by : Drilling fluid For log of strata over rock see
Log checked by : Barrel type : Engineering Log - Borehole
POINT LOAD o TESTDATA
DESCRIPTIONOF 0 DESCRIPTION cc <o ov
DRILLING ' H >-
CORE — OF <E DATA& LU 0 DEFECTS COMMENTS
w (2
U)
2 10 50 200 I- Cl)
U)
S 20 10050
4-
41
a .
) V Sf 0
0
/0 'U .4 o zi-
12-
SA/VOSTONE: pale grey, med/tim nained.
001VQ10Me4TE po/mc7'fc 00 OIn1 parlia I/
cemented d,o /5 (0f'/I..O,t4CR/tTE j' E.4A/LDSTONE: :à5 11 /nferóedded 5/35
Cnr/ornec'de :peA/uS7'O25n7m.
SOr)d5t00e: med/urn 7O CoapEC rained.
o. CON 0/VIERATE pa/e b/wth Feq, mcdaraAoly herd, ,oeb/ 0
?D 3-00
0 mm 0 side 18 - -
SANST0NE pa/i rsh brown medium -to c.oarse 11ained, modei'atef hard. _____
2o oj
P
P
I
I I I I I I I I L
r-
I P L
P L
P
$-T-__[.1.1 :1 1
ENGINEERING LOG - CORED BOREHOLE BOREHOLE NO.: 1 32 Sheet 2 of 5 Borehole location: R. L. Surface, Grid coordinates: Job No. : 1023G - 001 - 70
N: E:
Client 9 kJ. tv1ILL Co PTY LTD Datum: Project : MT TH0Ry 1_EASE
Location : S-aroN NSL,J Borehole inclination Borehole direction:
)From horizontal):
Hole commenced Drill type : RerE R.W. M11-LER Log describes all strata recovered El Hole completed : Mounted on : bILLst' RECo.n,s including soil over rock.
Supervised by : Drilling fluid
Log checked by : Barrel type : For log of strata over rock see El Engineering Log -- Borehole
POINT LOAD 0 z - 0
> (I)
TESTDATA
DESCRIPTION OF Cr DESCRIPTION I- F- DRILLING
CORE OF DATA&
DEFECTS cc 00— COMMENTS
0 20 50 200 U)
200050 o<
J C0NL0MRAT:
pole Llu,h mocJrcz7'a6( hard,
Po/yrnicl/c pe6//s 7'o 'tOmcn f)
' SI5e In Caap sand ma',h/x.
Th,/<-, 6c2c/ded and maSs/va. '2
22- I 3
1. 2 5l6ToN pale madiam gej ±0 Coaps,a graThad, mac/a haf7d, Th;ok/ f07'izrbea'4led.
CoNcLame/,4Te.' pa/a //7 to /5nms3e 0
SAN0.ST01VE: pale gr rned,thn to Coarsv ,qrained - -
CaNc 0M69A7E SAA/ASTONE 7hcea'g /27* added 60/527,
Cong/omerafe- oa/e /a/shgreg, 30- - - pe6,o/e.s /0 8mm dici. 0
Sandstone : pa/e yf7j. coarSe - 0 0
cirained. 0. 2
SANISTOIVC pa/a greg medium to Coarse graiaed, modenata/j hard.
C0A/cL0M5R4TE. pa/a &'uIShgrseJ. lo..o27 ,oebblas *0 20mmn a'/ci. .°. .2
0 SAA/osrot/E Coarse grainteci
CoNz-oMERATE: peA'ilss 'o 20mci dici. :o.
- $ANOSTOA/E 7m/ne 70 med/arr : :: grojnad. :. -.•. 1.0 2
s CoLoM,ATa: ,00/e 614116/i gre 0 -C
-o-2-
c/, e66/es to moclerafe/y /lar p 0 22n-m dia.
SAiJs.s7-aNe: (flaa'if to ______ :-r-:- graft7ad I I
- C0N0/1EA7-E . pe./as to 1517'm dic7. -
SANOSTONE pa/a greg.
Lmum gmiY. 4
FR
I Sw MW—ill FIGURE A8 W— I
L
I H I
I I I I I I I H F I I I H I
ENGINEERING LOG - CORED BOREHOLE BOREHOLE NO32 Sheet 3°f -
Borehole location: R. L. Surface, Grid coordinates: Job No. IO23, 001 -
N: Client R.W. MILLCR TO. E: Datum: Project : Mr. ThOltLaY LEASE
Location : Borehole inclination Borehole direction: (From horizontal):
Hole commenced : Drill type : MILL.Ef Log describes all strata recovered
Hole completed : Mounted on : ORILLINC, RECOKb.S L_J including soil over rock.
Supervised by : Drilling fluid
Log checked by : Barrel type : For log of strata over rock see Engineering Log - Borehole
POINT LOAD
Z 0 z—. TE ST DATA
CL DESCRIPTION OF Cc DESCRIPTION DRILLING
CORE i - OF <E DATA&
w DEFECTS _' COMMENTS
0 Ci)
2 CO 50 200 } (1) (Oz -
5 20 ioojso
.SANO STONE 00NL0MA7-
Thickly ,,7tepbedded SO/Sc, :0.; .3
ndstone : pale jn coan 10 .
-- grEtined
Con/omrafe:pa/e b/uihn 47 :ä - p.Lb/a.s up to /crrini
:— I.e
SAArnSTONE: 7L,e grsned SILTSTO,vE: rncderate(y
4.
SAivo.srovE.' pale qrey,L/ne hard1 9Pa/naa rnoda'rate/y -
fOfer/aminated and tddeO' wit/i Ei/i'.s/'Ofle (/o7). 35 &ic,d X 1.0
C Mudone o base. 46
/nt da 75° c/cI and / planar.
48 26
- . 60
52
3.9
54.
8.0
COAL 5AM: 4.7/5 lnefrvns WhY8Roi SEAM
-lhic/ç Th1r'cn/ahons s&frnants 378%, ofeqm
4 Mudstoria bards 'o.66m -i
4 Clays/-one /iand,s :0.34,s,
/ &/-/stone iands
M& On/u drnen/.s eat ifioo o .in +hicknes Shown = =
I-H - II SW --- II MW—Il FIGURE A9 HW-1 I EW
I I E I I I I
I I D I I I P L
P
H H I I
ENGINEERING LOG - CORED BOREHOLE BOREHOLENO.: 132 Sheet4of 5
Borehole location: R. L. Surface: Grid coordinates: Job No. : /023 - 00/ - 70
N: Client R. W. tS1/LLE Co Y L770 E: Datum: Project : MT T(op,y L0AS
Location : lALETb.j t'tsvi Borehole inclination Borehole direction: (From horizontal):
Hole commenced : Drill type : REFER F w. MILLER Log describes all strata recovered
Hole completed : Mounted on : DRILLINeT RCCOROS including soil over rock.
Supervised by : Drilling fluid
Log checked by : : Barrel type For log of strata over rock see Engineering Log - Borehole
POINT LOAD 0 . ° >U)
' cc0cl TEST DATA
rL DESCRIPTION OF ° DESCRIPTION I- -_ DRILLING
CORE - OF oE W 6 Ze w
0 X
DATA&
DEFECTS J u - Hw 00 COMMENTS
60 0
l_
2 :o 50200 I 5I05555
C/)
CLAY5TO NE. gí'eclish wh,'ta, - sof modøc'cz a/ hard.
.4
Si/tstcna and &,ncis tone bards at Lose. -- COAL. .SOA/t4. 0.7ei mefres
2/h intercakri4o,zs o/' Sediments 348 % eSeaM
64 SAIVOs-roNe. pale i'ej, a to med/am 'ed', tely I hard, rl7assíve, 1hc4/ &dded, Car,5o,-10 Ceous 7LraeS
(16
1.6
70
£c'ades a'lum to coarse - gra/ned.
72 CONLOM,ERATE: pa/a L/aih 0 0 5ra,, ,oe66/a.s t0 20 mm oa. l a
.9 SAlvOs TO/yE pa/a yrey, med/am t coar ,ned
74 -.
pole //aith 00 grey, ,oe&5/ag to 10mm dia.
* 1.1 SANOSTONE., pa/a med/am to camseQ1'.ir7ed,
7 moderafe/, , hard, it,/ In
7c5 -
FR SW Mw—
FIGURE AIO
I i I I I I I I I I I I I H I I I I H Li I
ENGINEERING LOG - CORED BOREHOLE BOREHOLE NO.: L32 Sheet 5of 6
Borehole location: R. L. Surfacer Grid coordinates: Job No. : I0231. - 001 -
N: Client : R.kJ. M(LLER Cco PY L.TC) E: Datum: Project : MT. YHORLEY L-EASff
Location : SlN35rErO . Nsj Borehole inclination Borehole direction: (From horizontal):
Hole commenced : Drill type : REFER R.lI. M(LLER r-i Log describes all strata recovered
Hole completed : Mounted on : c RE.CORt. LJ including soil over rock.
Supervised by : Drilling fluid
Log checked by : Barrel type : For log of strata over rock see Engineering Log - Borehole
POINT LOAD w Z -
0 0 >-
TESTDATA
DESCRIPTION OF - DESCRIPTION - DRILLING
CORE I I— i OF 0 Lu <E DATA&
DEFECTS COMMENTS
0 2 15 50 200 5 20 100
(Conk ) SANOTONC 5
82
84
S,LrTONC : 5rj, mod hapd.
- . . OIo) /5
I.8
CLAYSYQtvE.- pEla 3reqid broLcjn, so/f 7'o modaa t
_-
hard.
SANtSTONF S/LT5710fvE: litter-/a minahzd 5/35 {ine rautea',1oo/a f1efJ
ünd modrrahe/ hard. K 2.3 30
MUteTOAIE. dark qmodea.fe, $Q7C modarate , ,ard = COAL SEAM 0 750 in
ft7,erk.
52 x 5.5
MilEsTONE:
S14Ni2r57oNe- 1 9(L7ST01VE -- // a'cJild ,ht-rlamia fed,
5 /36, 4½e g/?2/02d saads/ane
S14AIDSTONE 0040 3p, 7Lie -777777
ln med/tim qranaa' moa'erafe/y
harl.
.4 SA WAS TONE 5/L7TONE: /nlzr/aminat'ed g nf-bzidder/,
735 Hi-I--- .Jofrtt, dip.a 40,
andsone: grrj, m'-iaa' JOfr4S 2o /'oens,a'€I _
TOiiJtcJ(ps4O sfi3hs'/j i a — — S/ic..f-tsi dad
darkyre, p.?Odra70ef.y ocd
COAL SEAM.' O-&SSm i'hicIc. 38
SA,VATO AlE c# .S,L.TSTONE lnfarbea'ded ' /n7'en/anhittahad
X 1. 1 SA v s in NE: pofa :• - meditim rir?ed. /
FR -
SW— MW FIGURE All HW—EW
IMATAIMIES 0 miuoo
I I I I I I I I I I I I I I I I I I I
flJS B WUOOE
ENGINEERING LOG — CORED BOREHOLE BOREHOLE NO.: 028 Sheet / of 3
Borehole location: R. L. Surface: 8. 50,,, Grid coordinates: Job No. : /0236 — 001 — 70
N: 1336750 Client : R. W. A411LER d Co Pry L70. E: 3o32503/ Datum: A.H.b. Project : M77. YHORLeY ZEASE
Location : SINLE70/y , /V,5.)/.
Borehole inclination Borehole direction:
(From horizontal): .900
Hole commenced : Drill type : Repee R.W. M/LLR Log describes all Strata recovered
Hole completed : Mounted on : DR/z.11v4 REOR0S. L_J including soil over rock.
Supervised by : Drilling fluid For log of strata over rock see
Log checked by : Barrel type : Engineering Log - Borehole
POINT LOAD
Z 0 >.. TESTDATA
F- LU
DESCRIPTION OF .. DESCRIPTION I— DRILLING
CORE I I OF <E cc
DATA&
W DEFECTS 00— COMMENTS
0 C')
2 10 50 200 F- "z
5 20 0055
Sl.rr SAND) r/ed,ii,n /0 ccars.e grained, pale brown.
C0AIL0MERA,TE.- poIyrsia tic cC'. ,oeL5b/e 1b 40 rrm. - . •. O Saó- anqil/ar to &ib- pounded.
Coo rse rno"). .auid a - 0.
00 o.
Muosroiis: 6rown Ia yreyish brown, Silly l pal' ts = 2.7
SANDSTONE 5ILT.ST0NE: ipterbea'cJed ' ,,tar/arn/naied
a/4o,
Sana stone: pate Lsroag) /2 .:.: .4 med/am grained
paralleL, sob- vertical, Si//stone; qrej to •greyisJ) frOWO
5Zm, sub-vent/cal. plane', minor Calcite lifsJl/ng,
dis *inuau a1 1-op, I
SANOSTON: pale brown, ine 14 - -to medium grained, bard and . : ps've. -
. 1
cainuoua' topI lo/tcm, generally qht. Sea/ed, ape"
-: /
. in pads, planar $
Medium I-a caar grained :, . .:• .0
rades /th l-o qreqish .s/ ornt,.sats-verfica/,apen, T:T.T brown, 'ne iInaaç Sidy ifl f, - :.: :- roLlyl,, planar, cont/nuau
at tap 607'7,77. 4t Or15.
iiwwwJi'2 FR sw
N
MW FIGURE 412 HW EW
I I I I I I I I
I I I I I I
I I I
KDA&MRS & FOOE
ENGINEERING LOG - CORED BOREHOLE BOREHOLE NO.: 028 SheetEof 5
Borehole location: R. L. Surface: Grid coordinates: Job No. : /036 - 00/ - 70
N: Client : R.kf. MILLeR Co Pry 47Z.
E: Datum: Project : MY. NORftY LCASE Borehole inclination Borehole direction:
(From horizontal): Location : £/N44_e7-o,v • N I-V
Hole commenced : Drill type : Log describes all strata recovered El Hole completed : Mounted on : including soil over rock. Supervised by : Drilling fluid
Log checked by : Barrel type : For log of strata over rock see Engineering Log — Borehole
POINT LOAD
Z E 0 0 0 Q. TESTDATA
Zo —
- CL DESCRIPTION OF DESCRIPTION F- F- DRILLING
CORE I I— LU
i CL
OF cr
DATA&
DEFECTS u, u. 2 t' n COMMENTS
tO 2 10 50 200 0 co —
5 20 105 5
Gradze to pole /-own, M2dium, Zo T t gi'ained I I 1.5
(rades -to pale qrey ne groined wi/h s,der,fe bond at 22 iocrri- ve't,ca/ -to ó / End of /,monfl Cenfre. .•;• ve1--hc01, opn,rou5, / planar hmoni/e stained. 1.2
Land Of ygy Si/lstone. 24
Cartsonaceous 74'aces iii hard, ma5j homojaneou -
1.2
San d.s/orie
- .1-
Crodes /',-j, o nye,J/im gre/ned * Scndsti,ae, wit/i minor - baod. T.
.4
30-
- -..: ..- 2.1
COAL .SEAM : 3. wifts WI-IYBROF- AM inferea/ations of Sediman/, 14-2% of team
2 C/ajs1ooe bands:0.2lm 34
in Micistane bands -. 0.25rn
N-s: On& sediments grter lt,an 0 f,-, -/hickne&s Shown
MUbSTo-iE - pale grey 1'o grey- 5AA/bSTO/JE; pale 52 /Iyv /h
hum 4.2
,Mun sroNe - Car-baflaca5 in parts.
COAL 5EAM: /.26-pnefYgs hik
41 it 2.1 FR
UIAI FIGURE AI EW 1
I I I I I I I I I I I I I I I I I I I I
IMANAMMS 0 M001140
ENGINEERING LOG - CORED BOREHOLE BOREHOLE NO.: 028 Sheet 3 of 3 Borehole location: R. L. Surface: Grid coordinates: Job No. : 10236 - 00/ - 70
N: Client : R. W. /l1/LLER CoPT)' L7() E: Datum: Project : M7 7-H0RLIY E4S
Location : SINLToN Borehole inclination Borehole direction: (From horizontal):
Ze commenced : Drill type : iii
Log describes all strata recovered
e completed : Mounted on : including soil over rock.
Supervised by : Drilling fluid
Log checked by : Barrel type : For log of strata over rock see Engineering Log - Borehole
- CL TESTDATA
DESCRIPTION OF 0
E —
DESCRIPTION DRILLING
I
PO IN T LO AD
CORE w I I— OF Zo
)
CL 0 DATA&
W DEFECTS cc
W LU f_ COMMENT S W
0 —
I- cj 2 10 50 200
1 1 5 120 100j50
Cl) 0 Z —
) Cf j.slone MUbST0iNE I
Hcia rE.R41M,.4TE1 &4c.3e0,T?.
42 -
I Sw MW—i! ! I FIGURE /:i4 EW -i
I L H I H I I I I I F F F I Li I I I H
2.8
4 ___ -- V GWL —o--o-
\
RESIDUAL DRAWDOWN CURVE:
\ PUMP WELL BB32
6 AVERAGE PUMPING RATE Q
= 9 GALLONS PER MINUTE
TRANSMISSIVITY, T = 264Q
Ls
T=43.9 GALLONS PER DAY PER FOOT
8
10- S = IS. 5 metres
= 54.1 feet
E
z 12-
0 0
0
-J
0 Ci) w 0
'0
I 2.5 5 10 100 300
RATiO, T(timeafterstartingtopump,minutes) -
T(time after stopping pump, minutes)
B
F(GURE A5 - ---
-
\ RESIDUAL DRA'NDOWN CURVE: PUMP WELL BB 30
° AVERAGE PUMPING RATE, Q = 8.95 GALLONS PER MINUTE
TRANSMISSMTY, T = 264 Q
Ls T= 70.6 GALLONS PER DAY PER FOOT
0
4-
5-
U,
- £s' = I0.2m
= 33.46 ft
C')
;! 7-
0 a
Ix a
8- -J
a U)
9-
I:
0 o
12- I 2 10 100 200
RATIO, T time after starting to pump, minutes) . T'(time after stopping pump, minutes) Ft GURE 416 a
I I I I I I I I I I I I I I
I I I I I
IC
0.2
0.4
0.6
0.8
2
MOM
RESIDUAL DRAWDOWN CURVE: OBSERVATION WELL BB30/1 (12.2m East of BB3O)
AVERAGE PUMPING RATE, 0 8.95 GALLONS PER MINUTE
TRANSMISSIVITY,T = 2640 Ls'
T = 306 GALLONS PER DAY PER FOOT
0
L\s'=. 2.35m
= 7.7IOft
10
100 RATIO , (time after starting to pump, minutes)
(time after stopping pump, minutes)
FIGURE A 16b
I I I I I I I I I I I I I I, I I I I I I
i 0.2
0.4-
0.6-
0.8 -
I .0-
1.2-
0)
1.4-
1.6- 0
0
-J
0 2.0-
2.2-
2.4-
2.6
2.8
0.5 2
RESIDUAL DRAWDOWN CURVE \ OBSERVATION WELL BB 30/2
\ \ (4.6m East of BB30)
\ AVERAGE PUMPING RATE
8.95 GALLONS PER MINUTE
\\ TRANSMISSIVITY, T =
\ Ls' 0 T= 300 GALLONS PER FOOT PER DAY
I
2.40m = 7. 87ft
10 tOO RATIO , T (time after starling to pump, minules)
T (time otter stopping pump, minutes)
B OE
FIGURE A16c
2 -...
I RESIDUAL DRAWDOWN CURVE
\\ PUMP WELL 8828
I AVERAGE PUMPING RATE , Q = 15 GALLONS PER MINUTE
I' TRANSMISSIVITY, T = 2640
Ls, 4 T 132.6 GALLONS PER DAY PER FOOT
I I
I0
= 9.1m
= 29 86 ft
\\\\\
co Lu
10 100 300
I RATIO, T time after starting to pump, minutes)
T (time after stopping pump, minutes) IMMMIES B
FIGURE A17
1
RESULTS OF SLAKE DURABILITY TESTS
Borehole Depth
Rock Type Durability Classification
(in)
AA24 55.67 Siltstone
AA24 95.97 Conglomerate
BB24 74.20 Medium-coarse Sandstone
BB28 56.80 Laminated Sandstone/ Siltstone
BB28 126.54 Medium Sandstone
BB28 160.14 Interlaminated Sandstone! Siltstone
BB32 44.50 Siltstone with carbonaceous wisps
L32 37.83 Medium-coarse Sandstone
L32 45.63 Laminated Sandstone/ Siltstone
L32 50.53 Laminated Sandstone/ Siltstone with carbonaceous wisps
X28 46.3 Fine Sandstone with carbonaceous wisps
X28 72.6 Fine Sandstone with carbonaceous wisps
Z24 137.84 Carbonaceous Mudstone
Z28 180.55 Interlaminated Sandstone! Siltstone
Z32 168.32 Interlaminated Sandstone! Siltstone
Medium High
High
Very High
Very High
High
Medium
Very High
Medium High
High
High
High
Medium High
Medium High
Medium
The object of the slake-durability test is to assess the suseptibility of a
rock sample to breakdown when subjected to cycles of wetting and drying.
The apparatus consists of a drum with 2mm mesh wall which rotates at 20r
on a central axle in a bath of water.
Figure 7,13
The procedure for the test is to prepare ten rounded pieces of the rock sample
of approximately 50g each, oven dry them, then place them in the mesh drum and
rotate for 10 minutes. The drum and contents is then removed from the water
bath and oven dried to a constant weight. The sample is subjected to the
wetting and drying cycle twice. Sample weights are recorded after each
drying. The slake-durability index (second cycle) is calculated as the
percentage ration of the final dry weight to the initial dry weight, thus:
Slake-durability index Id2 = Final dry weight
100 Initial dry weight
The rock durability is classified from the Slake-durability Index, ranging
as follows:
Id2 (%) Classification
0 - 30 Very low
30-60 Low
60 - 85 Medium
85 - 95 Medium high
95 - 98 High
98 - 100 Very high
Figure A19
- - - - - - - - - - - - - - - - - - - - TABLE: ESTIMATES OF PIT INFLOW RATES (GPM) FROM THE
GLEN MUNRO/WOODLANDS HILL SEAM IN THE PUMP-OUT TESTS
FOR BOREIIOLES BB30 AND BB32
Borehole Inf low Rates (GPM) for Pit Dimensions: Width (Metres) x Lengths (Metres)
No. 30m x 30m 30m x 30m 30m x 1500m 30m x 1500m lOOm x lOOm lOOm x lOOm lOOm x 1500m lOOm x 1500m
After 100 After 1000 After 100 After 1000 After 100 After 1000 After 100 After 1000 days days days days days days days days
BB28 3 2 13 5 4 3 13 6
3B30 21 17 55 26 29 21 61 31
EB32 4 3 19 7 6 4 20 8
- - - - - - -. - - - - - - - - - - - - - TABLE: ESTIMATES OF PIT INFLOW RATES (GPM) FROM THE
GLEN MUNRO/WOODLANDS HILL AND PIERCEFIELD SEAMS
IN THE PUMP-OUT TEST FOR BOREHOLE BB28
Borehole Inflow Rates (GPM) for Pit Dimensions: Width (Metres) x Length (Metres)
No: 30m x 30m 30m x 30m 30m x 1500m 30m x iSOOm lOOm x lOOm lOOm x lOOm lOOm x 1500m lOOm x 1500m After 100 After 1000 After 100 After 1000 After 100 After 1000 After 100 After 1000 days days days days days days days days
BB28 51 40 176 80 72 52 191 79