ORP GAL MJT Interim Stage 1 and 2 Geotechnical Data Report ... · PDF fileGolder Associates...

April 2011

UPDATED INTERIM GEOTECHNICAL DATA REPORT

Geotechnical and Hydrogeological Investigation Ottawa Light Rail Transit (OLRT) Tunnel (Segment 2 - Stage 1 and Stage 2) Ottawa, Ontario

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Report Number: 10-1121-0222

Distribution:

2 copies - Capital Transit Partners (CTP)

2 copies - Golder Associates Ltd.

Submitted to:Capital Transit Partners 24 Floor, 160 Elgin Street Ottawa, Ontario K2P 2P7

UPDATED INTERIM GDR – OLRT TUNNEL (STAGE 1 & STAGE 2)

April 2011 Report No. 10-1121-0222 i

Table of Contents 1.0 INTRODUCTION ............................................................................................................................................................... 1

1.1 Overview and Purpose ........................................................................................................................................ 2

2.0 SITE DESCRIPTION ......................................................................................................................................................... 3

3.0 INVESTIGATION PROCEDURES .................................................................................................................................... 4

3.1 Boreholes ............................................................................................................................................................ 4

3.1.1 Drilling ............................................................................................................................................................ 6

3.1.2 Hydrogeological Testing ................................................................................................................................. 7

3.1.3 Geotechnical Logging .................................................................................................................................. 11

3.1.3.1 Soil Logging .............................................................................................................................................. 11

3.1.3.2 Rock Logging ............................................................................................................................................ 12

3.2 Borehole Geophysical Logging .......................................................................................................................... 17

3.2.1 Methodology ................................................................................................................................................ 17

3.2.2 Geophysical Logging Procedure .................................................................................................................. 19

3.3 In Situ Stress Measurements ............................................................................................................................. 20

3.4 Geological Mapping ........................................................................................................................................... 20

4.0 LABORATORY TESTING .............................................................................................................................................. 21

5.0 REGIONAL GEOLOGY .................................................................................................................................................. 23

5.1 General .............................................................................................................................................................. 23

5.2 Regional Tectonic and Seismic Setting ............................................................................................................. 23

6.0 MAJOR GEOLOGICAL STRUCTURES ......................................................................................................................... 24

6.1 Faulting .............................................................................................................................................................. 24

6.2 Bedding and Discontinuity Sets ......................................................................................................................... 25

6.2.1 Geological Mapping ..................................................................................................................................... 25

6.2.2 Mapped Structural Data ............................................................................................................................... 26

6.2.3 Borehole Structural Data .............................................................................................................................. 27

7.0 SUBSURFACE CONDITIONS ........................................................................................................................................ 29

7.1 Overburden ........................................................................................................................................................ 29

7.1.1 General ........................................................................................................................................................ 29

7.1.2 Topsoil, Pavement and Fill ........................................................................................................................... 30


April 2011 Report No. 10-1121-0222 ii

7.1.3 Silty Clay/Clayey Silt .................................................................................................................................... 31

7.1.4 Sand and Silt ................................................................................................................................................ 33

7.1.5 Glacial Till .................................................................................................................................................... 34

7.2 Bedrock ............................................................................................................................................................. 37

7.2.1 Laboratory Testing ....................................................................................................................................... 38

7.2.2 Rock Mass Quality ....................................................................................................................................... 44

7.3 Groundwater and Hydraulic Conductivity ........................................................................................................... 46

7.4 In Situ Stress Measurements ............................................................................................................................. 51

8.0 CLOSURE ....................................................................................................................................................................... 54

REFERENCES ......................................................................................................................................................................... 55

Important Information and Limitations of this Report

TABLES Table 3-1: Summary of Boreholes .............................................................................................................................................. 4

Table 3-2: Summary of Packer Testing ...................................................................................................................................... 8

Table 3-3: Density Index (CFEM, 2006) ................................................................................................................................... 11

Table 3-4: Consistency of Cohesive Soils (CFEM, 2006) ........................................................................................................ 11

Table 3-5: Sensitivity Descriptions of Cohesive Soils (CFEM, 2006) ....................................................................................... 12

Table 3-6: Soil Constituents (CFEM, 2006) .............................................................................................................................. 12

Table 3-7: Estimation of Rock Hardness (ISRM, 1981) ............................................................................................................ 13

Table 3-8: Weathering Classification (after ISRM 1981) .......................................................................................................... 14

Table 3-9: Joint Roughness, Jr (after Barton et al. 1974) ......................................................................................................... 16

Table 3-10: Joint Alteration, Ja (after Barton et al. 1974) ......................................................................................................... 16

Table 3-11: Joint Condition, Jcon (after Bieniawski 1976) ....................................................................................................... 17

Table 3-12: Summary of Geophysical Logging Suites ............................................................................................................. 17

Table 3-13: Summary of Geophysical Logging for Each Borehole ........................................................................................... 19

Table 4-1: Summary of Laboratory Tests ................................................................................................................................. 21

Table 6-1: Geological Mapping Structural Data ........................................................................................................................ 27

Table 6-2: Joint Set Orientations .............................................................................................................................................. 27

Table 7-1: Summary of Silty Clay (Weathered Crust) Soil Samples in Rideau Valley .............................................................. 31

Table 7-2: Summary of Silty Clay Soil Samples in Rideau Valley ............................................................................................ 32

Table 7-3: Summary of Silty Clay (Weathered Crust) Soil Samples at the East Portal ............................................................ 32

Table 7-4: Summary of Silty Clay Soil Samples at the East Portal ........................................................................................... 32


April 2011 Report No. 10-1121-0222 iii

Table 7-5: Summary of Silt Samples in Rideau Valley ............................................................................................................. 33

Table 7-6: Summary of Sand Samples in Rideau Valley .......................................................................................................... 34

Table 7-7: Summary of Silt Samples at the East Portal ........................................................................................................... 34

Table 7-8: Summary of Glacial Till Samples at the West Portal ............................................................................................... 35

Table 7-9: Summary of Glacial Till Sample on the Tunnel Alignment ...................................................................................... 35

Table 7-10: Summary of Glacial Till Samples in Rideau Valley ................................................................................................ 36

Table 7-11: Summary of Rock Formations Encountered in OLRT Study Area ......................................................................... 37

Table 7-12: Summary of UCS Testing ..................................................................................................................................... 39

Table 7-13: Summary of Point Load Index (Is50) ..................................................................................................................... 40

Table 7-14: Summary of Tensile Testing ................................................................................................................................. 40

Table 7-15: Summary of Direct Shear Testing ......................................................................................................................... 41

Table 7-16: Summary of Triaxial Testing ................................................................................................................................. 41

Table 7-17: Summary of Lindsay Formation Abrasion and Drillability Results ......................................................................... 42

Table 7-18: Summary of Verulam Formation Abrasion and Drillability Results ........................................................................ 42

Table 7-19: Summary of Petrographic Analyses ...................................................................................................................... 43

Table 7-20: Summary of Whole Rock Analyses ....................................................................................................................... 43

Table 7-21: Summary of Measured Static Water Levels .......................................................................................................... 46

Table 7-22: Summary of Field Hydraulic Conductivity Test Results ......................................................................................... 47

Table 7-23: Summary of Hydraulic Conductivity Packer Test Results in Rock ......................................................................... 48

Table 7-24: Hydrofracture Testing Zones and Lithology .......................................................................................................... 52

Table 7-25: Summary of Calculated Stress Values in the Global Co-ordinate System ............................................................ 53

FIGURES

Figure 1.1: Project Segments Figure 1.2: Borehole Location Plan Figure 3.1: Regional Geology Figure 5.1: Historical Seismicity Figure 6.1: Inferred Formation Boundaries Figures 6.2A to D: Interim Geological Plan and Profile Figure 6.3: Structural Data – Contoured Stereonets Figure 6.4: Structural Data – Combined Outcrop and Televiewer Figure 7.1: Summary of Undrained Shear Strength vs. Elevation Figure 7.2: Summary of Water Contents vs. Elevation (Grey Silty Clay / Clayey Silt) Figure 7.3: Static Groundwater Levels – Boreholes T-5, T-10, T-12, and T-13 Figure 7.4A to D: Interim Hydrogeological Plan and Profile


April 2011 Report No. 10-1121-0222 iv

APPENDICES

APPENDIX A List of Abbreviations and Symbols Lithological and Geotechnical Rock Description Terminology Scoped Phase II ESA Record of Borehole Sheets

APPENDIX B List of Abbreviations and Symbols Lithological and Geotechnical Rock Description Terminology Discontinuity Description Record of Borehole and Drillhole Sheets

APPENDIX C Geotechnical Core Photographs

APPENDIX D Downhole Geophysical Log Discontinuity Description Downhole Geophysical Logs

APPENDIX E Laboratory Test Results

APPENDIX F In Situ Stress Measurements

APPENDIX G Acoustic Televiewer Contoured Stereonet Plots

APPENDIX H Hydrogeological Field Testing


April 2011 Report No. 10-1121-0222 1

1.0 INTRODUCTION Golder Associates Ltd (Golder) was retained by Capital Transit Partners (CTP) on behalf of the City of Ottawa

Rail Implementation Office to carry out a preliminary geotechnical/hydrogeological investigation for the proposed

Ottawa Light Rail Transit (OLRT) project.

For reporting purposes, the OLRT alignment has been divided into 5 segments (see Figure 1.1):

Segment 1 – Tunney’s Pasture Station to West Tunnel Portal (West At-Grade);

Segment 2 – Downtown Tunnel, West Tunnel Portal to East Tunnel Portal;

Segment 3 – East Tunnel Portal to just east of Hurdman Station;

Segment 4 – Just east of Hurdman Station to just west of the tunnel under Hwy 417, including the

Maintenance Area; and,

Segment 5 – West of the tunnel under Hwy 417 to Blair Station.

Segment 1 is referred to as the West At-Grade segment, Segment 2 is referred to as the Downtown Tunnel

segment and the latter three segments (3, 4 and 5) are collectively referred to as the East At-Grade portion of

the project alignment.

This updated draft interim geotechnical data report (GDR) presents the factual results for the Tunnel Section

(Segment 2). The factual results for the remainder of the OLRT project segments are reported under separate

covers.

The geotechnical and hydrogeological field investigation for this project is planned to be carried out in three

stages. Stage 1 was carried out from May 3 to August 11, 2010. The interim geotechnical data report (GDR) for

Stage 1 was submitted under a separate cover “Interim Geotechnical Data Report, Geotechnical and

Hydrogeological Investigation, Ottawa Light Rail Transit Tunnel, Ottawa, Ontario”, Report Number 10-1121-

0068-1 dated December 2010.

Stage 2 of the field program, which was carried out from October 7, 2010 to January 13, 2011, included borehole

drilling, hydrogeological testing, in situ stress measurements, downhole geophysics logging and laboratory

testing all of which are discussed in detail below.

This draft updated Geotechnical Data Report provides the results from the Stage 1 and Stage 2 geotechnical

and hydrogeological investigations.

The third and final stage of the tunnel field program commenced March 21, 2011 and the results from that

investigation will be provided in a further revision of this GDR.

The reader is referred to the “Important Information and Limitations of This Report” which follows the text but

forms an integral part of this document.


April 2011 Report No. 10-1121-0222 2

1.1 Overview and Purpose The OLRT project involves the construction of a new transit facility which will comprise approximately

12.5 kilometres (km) of new electrified light rail transit (LRT) between Tunney’s Pasture and Blair Road in the

City of Ottawa, and the construction of a vehicle maintenance and storage facility located to the south of

Segment 4 of the LRT system. The majority of the LRT construction will involve the conversion of the existing

Transitway to LRT. The conversion will occur in the sections between Tunney’s Pasture and east of Le Breton

Station (west at-grade section), and from about Waller Street to Blair Road (east at-grade section). The central

portion (tunnel section) will be in twin-bored tunnels. Thirteen LRT stations have been identified along the

proposed route. Three stations (Downtown West, Downtown East, and Rideau) will be constructed below grade,

along the tunnel, serving the downtown area.

The tunnel and station alignment and configuration shown in this report are based on the Revision 1 Alignment

dated January 17, 2011 provided by CTP. The tunnel alignment shown in this report is subject to change based

on additional borings and modifications to the design. This report presents the factual results from the interim

geotechnical and hydrogeological investigations carried out for the tunnel section of the OLRT project during the

period from May 3 to August 11, 2010 (Stage 1) and October 8 to January 13, 2011 (Stage 2). Locations of the

Stage 1 and Stage 2 boreholes are identified on Figure 1.2.

A limited Phase II Environmental Site Assessment was also carried out for this project and the results of that

investigation are contained in the report “Factual Report, Scoped Phase II Environmental Site Assessment,

Preliminary Design, Ottawa Light Rail Transit Tunnel, Ottawa, Ontario”, Report Number 10-1121-0068 (5000)

dated September 2010. The locations of the boreholes advanced during that investigation are also indicated on

Figure 1.2 and the Record of Borehole Sheets are provided in Appendix A.


April 2011 Report No. 10-1121-0222 3

2.0 SITE DESCRIPTION The OLRT tunnel alignment extends approximately 2.4 km within twin bored tunnels. The elevations discussed

below are referenced to Geodetic datum (Canadian Vertical Datum, 1928).

At the west portal, the ground surface slopes modestly from about elevation 62 metres, along the entrance to the

portal, to about elevation 74 metres between Bronson and Bay Street. The area in the vicinity of the portal

consists of a small City park bounded by roadways and parking lots to the west, north and south of the portal.

At the eastern boundary of the park, a bedrock escarpment extends north from the portal towards the Ottawa

River. This escarpment may be considered the western boundary of the downtown core of Ottawa.

The tunnel alignment then extends through the downtown core of Ottawa in a typical major urban setting.

The ground surface along this section of the alignment varies relatively gently in elevation from about 71 to

76 metres. Numerous high rise buildings and building complexes extend along Albert Street which is also a high

volume transit corridor. At Kent Street, the tunnel alignment turns northward to extend obliquely under Queen

Street, Sparks Street and the National War Memorial at the intersection of Elgin and Wellington Street, in the

process crossing under several downtown buildings.

East of the war memorial, the tunnel alignment crosses under the Rideau Canal, a national landmark and a

UNESCO designated world heritage site. The invert of the canal at this location is indicated to be between about

elevation 62 and 63 metres.

From the canal, the alignment extends east along Rideau Street through a major shopping area and then turns

south along Waller Street. From the east side of the canal to Rideau Street, just east of Colonel By Drive, the

ground surface drops from about elevation 69 metres to about elevation 64 metres. The ground surface along

Rideau Street is relatively level at about elevation 64 metres and then rises as the alignment turns to meet

Waller Street to about elevation 70 metres. Waller Street is a major urban thoroughfare populated with mid and

high rise residential and commercial buildings.

South of Laurier Avenue, the tunnel alignment extends across the Transitway embankment, past the south end

of Waller Street, and the ground surface rises to about elevation 72 metres before dropping somewhat abruptly

to about elevation 67 metres. The ground surface elevation then drops gently to about elevation 60 metres at

the east portal. The tunnel east portal is located at Laurier Avenue and Waller Street. From the intersection of

Waller Street and the Transitway, the alignment extends along the grassed parks adjacent to the Rideau Canal

and then, after re-crossing to the east side of the Transitway, extends below mostly undeveloped lands adjacent

to the Transitway and the Highway 417 ramps.


April 2011 Report No. 10-1121-0222 4

3.0 INVESTIGATION PROCEDURES

3.1 Boreholes The geotechnical drilling for Stage 1 was carried out between May 3 and July 15, 2010. During that period,

sixteen boreholes (numbered T-1 to T-16, inclusive) were drilled within the tunnel alignment at the locations

shown on Figure 1.2. Eleven environmental boreholes shown on Figure 1.2 were also drilled within the tunnel

alignment during this period, but are discussed in the report “Factual Report, Scoped Phase II Environmental

Site Assessment, Preliminary Design, Ottawa Light Rail Transit Tunnel, Ottawa, Ontario”, Report Number 10-

1121-0068 (5000) dated September 2010.

The geotechnical drilling for Stage 2 was carried out between October 7 and December 22, 2010. During that

period, thirteen geotechnical boreholes (T-35 to T-36, T-39 to T-44, T-46, T-48 and T-51 to T-53), seven

combined geotechnical-environmental boreholes (T-47 and W-057 to W-062), and two environmental boreholes

(T-AI and T-AL) were drilled within the tunnel alignment at the locations shown on Figure 1.2. The

environmental boreholes drilled during Stage 2 will be discussed in a separate report.

Table 3-1 lists the borehole locations along the alignment, borehole dip, dip direction (relative to True North),

drilled lengths and depths:

Table 3-1: Summary of Boreholes

Borehole No.

Location Geotechnical (G)

Environmental (E) Combined (GE)

Borehole Dip/Dip

Direction (3)

Drilled Length (m)

Drilled Depth (m)

T-1 West Portal G 68 / 141 31.9 29.6

T-2 West Portal G 70 / 270 33.2 31.2

T-3 Tunnel G 72 / 053 51.8 49.3

T-4 Downtown West Station G 72 / 053 52.8 50.2

T-5 Downtown West Station G 68 / 243 54.4 50.4

T-6 Tunnel G 68 / 243 52.9 49.0

T-7 Downtown East Station G 67 / 243 52.7 48.5


T-9 Tunnel G 70 / 058 57.6 54.2

T-10 Rideau Station G 69 / 332 45.3 42.3


T-12 Tunnel - Bedrock Valley G 90 / NA 36.1 36.1(1)

T-13 Tunnel - Bedrock Valley G 89 / 027 40.5 40.5

T-14 Tunnel G 69 / 060 39.5 36.9

T-15 Tunnel G 69 / 234 38.0 35.5

T-16 Tunnel G 71 / 206 35.0 33.1

T-35 Tunnel G 90 / NA 32.0 32.0

T-36 Tunnel G 90 / NA 31.8 31.8

T-39 Tunnel G 69 / 244 42.0 39.2

T-40 Rideau Station G 90 / NA 30.1 30.1(2)


April 2011 Report No. 10-1121-0222 5

Borehole No.

Location Geotechnical (G)

Environmental (E) Combined (GE)

Borehole Dip/Dip

Direction (3)

Drilled Length (m)

Drilled Depth (m)

T-41 Rideau Station G 90 / NA 45.1 45.1


T-43 Tunnel G 72 / 244 57.2 54.4



T-47 Downtown West Station GE 90 / NA 50.2 50.2

T-48 Downtown West Station G 90 / NA 49.9 49.9



T-53 Rideau Station G 90 / NA 36.9 36.9

W-057 West Portal GE 90 / NA 12.0 12.0






T-AA West Portal E 90 / NA 6.1 6.1

T-AB Downtown West Station E 90 / NA 8.7 8.7

T-AC Downtown West Station E 90 / NA 5.7 5.7

T-AD Tunnel E 90 / NA 6.1 6.1

T-AE Tunnel E 90 / NA 5.9 5.9

T-AF Downtown East Station E 90 / NA 5.7 5.7

T-AG Downtown East Station E 90 / NA 9.1 9.1

T-AH Tunnel E 90 / NA 6.3 6.1

T-AI Downtown East Station E 90 / NA 6.1 6.1

T-AJ Rideau Station E 90 / NA 4.8 4.8

T-AK Tunnel E 90 / NA 6.1 6.1

T-AL Tunnel E 90 / NA 6.0 6.0

Total 1639.9 1497.4

Notes:

(1) Borehole T-12 was not drilled to its planned depth of 40.4 metres due to several factors such as limited work hours and difficult soil conditions. (2) Borehole T-40 was not drilled to its planned depth of 40.4 metres due to difficult soil conditions. (3) Borehole dip is measured from horizontal. Borehole dip direction is measured clockwise relative to true north.


April 2011 Report No. 10-1121-0222 6

After the final depth was reached, the boreholes were left open (with flush mount cover in place) for up to

approximately one month to conduct geophysical logging within the boreholes.

On completion of the drilling operations, the soil and rock samples from the boreholes were transported to

various laboratories for testing and to an off-site storage facility for examination by the project engineer.

Due to the proximity of existing underground utilities, it was sometimes necessary to remove the pavement

structure and the first few meters of the overburden soils. During Stage 1, hydro-vacuuming techniques were

used at boreholes T-5, T-9 and T-12. During Stage 2, hydro-vacuuming techniques were used at boreholes T-

41, T-43, T-44, T-46, T-47, T-51, T-52 and T-53. Following the geophysical logging or decommissioning of

boreholes, the backfill and pavement structure or interlock bricks were reinstated at those respective boreholes.

In addition, the asphalt was removed and reinstated at borehole T-4 due to damage caused by flush water.

For Stage 1, landscape repairs were carried out at boreholes T-1 and T-2 after the fieldwork was completed.

Landscape repairs will be carried out at some borehole locations due to damages caused by the Stage 2 field

work.

During Stage 1, monitoring wells were installed in boreholes T-5, T-10, T-12 and T-13 and during Stage 2, a

monitoring well was installed in borehole T-35 to allow subsequent measurement of the stabilized groundwater

level at the site and for field permeability (rising head) testing. In situ hydraulic conductivity (packer) testing was

also carried out within select boreholes.

Boreholes in which monitoring wells were not installed were backfilled with a cement-bentonite grout.

The field work was supervised by experienced Golder personnel who located the boreholes, directed the drilling

operations, geotechnically logged the boreholes, took custody of the samples, and carried out the in situ testing.

The borehole locations were selected and located in the field by Golder Associates personnel and the locations

and elevations were subsequently surveyed by Annis O’Sullivan Vollebekk Ltd. The elevations are referenced to

Geodetic datum (Canadian Vertical Datum, 1928).

3.1.1 Drilling

During Stage 1, fifteen boreholes were advanced using truck-mounted drill rigs operated by George Downing

Estate Drilling Ltd. of Grenville-sur-la-rouge, Quebec. One borehole was also advanced using a truck-mounted

drill rig operated by Marathon Drilling Company Ltd. of Ottawa, Ontario. The boreholes were advanced to

depths which varied from 29.6 to 54.0 metres below ground surface.

During Stage 2, seventeen boreholes were advanced using truck-mounted drill rigs operated by George

Downing Estate Drilling Ltd. Three boreholes were also advanced using a track-mounted drill rig operated by

Marathon Drilling Company Ltd. One borehole was advanced using a sonic drill rig operated by Boart Longyear

of Marysville, Ontario. The tunnel boreholes were advanced to depths which varied from 12.0 to 60.4 metres

below ground surface.

Standard penetration tests (SPT) (ASTM D 1586) were conducted at regular depth intervals in boreholes T-35,

T-36, T-40, T-41, T-47, T-48 and W-057 to W-062, inclusive during Stage 2. A rope and cathead hammer drop

system was used and samples of the soils encountered were recovered using drive-open sampling equipment.


April 2011 Report No. 10-1121-0222 7

In situ vane testing was carried out within the silty clay at boreholes T-35, T-36 and T-40 (Stage 2) to evaluate

the undrained shear strength of this soil unit.

Within boreholes where bedrock was estimated to be deeper (T-12 and T-13) the soil was sampled using PQ

sized rotary soil coring equipment along with standard penetration tests (SPT) (ASTM D 1586) at regular depth

intervals.

Sonic drilling was employed at borehole T-53 using a high-frequency, resonate energy to advance the core

barrel and casing into the subsurface. Continuous samples of the overburden were recovered and placed into

plastic bags or plastic liners.

All boreholes with the exception of T-40 and T-53 were advanced into the underlying bedrock using HQ sized

rotary core drilling equipment and a triple tube core barrel. The bedrock core was sequentially placed into core

boxes for transport and storage. During Stage 1, fifteen boreholes were drilled at an inclination of approximately

70 degrees from horizontal to lengths varying from 31.9 to 57.6 metres which corresponds to depths of about 30

to 54 m below ground surface. During Stage 2, four boreholes were drilled at an inclination of approximately 70

degrees from horizontal to lengths varying from 42.0 to 57.2 metres which corresponds to depths of about 39.2

to 54.4 metres below ground surface. Three boreholes were drilled at an inclination of approximately 40 degrees

from horizontal to lengths varying from 83.3 to 92.1 metres which corresponds to depths of about 55.7 to 60.4

metres below ground surface. The inclined boreholes are primarily intended to provide information on bedrock

quality and geotechnical properties as only limited sampling and in situ testing is possible within the overburden

soils of the inclined boreholes.

Fracture and discontinuity data were recorded based on a visual inspection of the recovered rock core extracted

from the core barrel. The orientation of the core was determined using a core orientation tool (ACE

manufactured by Reflex Instruments); an electronic instrument which records the orientation with regard to its

original position after it has been removed from the ground.

3.1.2 Hydrogeological Testing

In situ hydraulic conductivity testing was carried out in selected boreholes to assess the permeability

characteristics of the rock formations and rock structure encountered. The packer test locations ranged from

approximately 4 to 54 m vertically below ground surface. Packer testing was carried out within boreholes T-1, T-

3, T-5 to T-11 and T-13 to T-16 (Stage 1) and T-35, T-36, T-39, T-41, T-42, T-43, T-44, T-46, T-47, T-48, T-51

and T-52 (Stage 2).

The downhole testing equipment consisted of a single pneumatic packer, manufactured by RST Instruments

Ltd., which was lowered down the HQ-sized drill rods using AQ-sized rods. The packer was subsequently

inflated with nitrogen gas to isolate the test interval. A vibrating wire pressure gauge was used to monitor and

record real-time pressure responses during the tests. Falling head and/or constant head tests were conducted

to determine hydraulic conductivity values for the test intervals.

For a falling head test, a hydraulic head was applied to the test interval via a column of clean water within the

AQ-sized rods. The drop in the hydraulic head (or water level) was then monitored over time as it recovered to

the pre-test static water level. The recovery data of the falling head tests were analyzed using Hvorslev’s (1951)

method to calculate the hydraulic conductivity of the rock mass interval.


April 2011 Report No. 10-1121-0222 8

In zones with higher permeability, where the falling head testing showed rapid hydraulic head loss, constant

head tests were performed and the data was processed using Hvorslev’s constant head interpretation method

(Hvorslev, 1951). The constant head tests were carried out using the Lugeon method, which consisted of

inducing varying constant pressure head intervals using a pump on surface and monitoring the flow rate, with a

flow meter.

The following table lists the number of packer tests, the test interval and elevation for each packer test.

Table 3-2: Summary of Packer Testing

Borehole No.

No. of Packer Tests

Downhole Interval (m along borehole)

Elevation Interval (m above sea level)

T-1 3

9.00 – 15.30 m 57.37 – 51.52 m

13.60 – 21.30 m 53.10 – 45.96 m

20.10 – 31.94 m 47.07 – 36.10 m

T-3 1 24.20 – 35.00 m 43.30 – 33.03 m

T-5 3

26.30 – 34.70 m 47.29 – 39.39 m

36.60 – 45.40 m 37.61 – 29.34 m

46.30 – 54.36 m 28.49 – 20.92 m

T-6 1 19.70 – 52.86 m 53.60 – 22.86 m

T-7 3

9.30 – 22.60 m 62.70 – 50.46 m

22.60 – 39.36 m 50.46 – 35.03 m

37.60 – 52.73 m 36.65 – 22.72 m

T-8 3

11.30 – 28.90 m 61.81 – 44.98 m

28.30 – 43.90 m 45.56 – 30.64 m

41.10 – 53.50 m 33.32 – 21.46 m

T-9 3

8.70 – 18.10 m 66.06 – 57.23 m

17.90 – 36.30 m 57.42 – 40.13 m

34.90 – 57.60 m 41.44 – 20.11 m

T-10 3

4.10 – 14.80 m 63.08 – 53.09 m

13.30 – 30.00 m 54.49 – 38.90 m

28.30 – 45.31 m 40.49 – 24.61 m

T-11 3

16.30 – 26.90 m 49.75 – 39.79 m

25.20 – 36.00 m 41.39 – 31.24 m

34.30 – 44.98 m 32.84 – 22.80 m


April 2011 Report No. 10-1121-0222 9

Borehole No.

No. of Packer Tests



T-13 2 8.70 – 21.00 m 55.10 – 42.80 m

19.30 – 40.50 m 44.50 – 23.31 m

T-14 2 6.30 – 19.70 m 58.37 – 45.86 m

18.60 – 39.49 m 46.89 – 27.38 m

T-15 2 8.10 – 22.70 m 61.47 – 47.84 m

20.30 – 38.01 m 50.08 – 33.54 m

T-16 2 7.60 – 18.40 m 62.82 – 52.61 m

16.70 – 35.03 m 54.22 – 36.89 m

T-35 3

10.36 – 16.43 m 60.78 – 54.71 m

16.10 – 23.91 m 55.04 – 47.23 m

24.45 – 32.00 m 46.69 – 39.14 m

T-36 3

11.43 – 16.52 m 59.10 – 54.01 m

16.35 – 22.66 m 54.18 – 47.87 m

22.95 – 31.76 m 47.58 – 38.77 m

T-39 3

14.35 -– 23.40 m 49.92 – 41.47 m

22.61 – 4.41 m 42.21 – 31.20 m

33.12 – 41.95 m 32.40 – 24.16 m

T-41 3

16.14 – 25.50 m 50.11 – 40.75 m

25.16 – 34.48 m 41.09 – 31.77 m

34.69 – 45.11 m 31.56 – 21.14 m

T-42 3

18.01 – 24.03 m 48.45 – 42.66 m

23.97 – 34.27 m 42.72 – 32.82 m

34.21 – 46.17 m 32.88 – 21.38 m

T-43 3

9.31 -–15.46 m 68.53 – 62.68 m

15.13 – 25.93 m 62.99 – 52.72 m

25.64 – 36.57 m 52.99 – 42.60 m

35.52 – 57.15 m 43.60 – 23.03 m


April 2011 Report No. 10-1121-0222 10

Borehole No.

No. of Packer Tests



T-44 3

25.48 – 36.16 m 49.16 – 39.25 m

35.98 – 45.13 m 39.42 – 30.94 m

44.98 – 55.63 m 31.08 – 21.20 m

T-46 4

36.01 – 48.18 m 47.59 – 39.60 m

48.16 – 60.23 m 39.61 – 31.70 m

59.59 – 72.36 m 32.12 – 23.74 m

71.63 – 83.06 m 24.22 – 16.72 m

T-47 4

7.49 – 16.75 m 65.00 – 55.74 m

16.55 – 25.86 m 55.94 – 46.63 m

25.73 – 36.42 m 46.76 – 36.07 m

36.47 – 50.15 m 36.02 – 22.34 m

T-48 4

15.17 – 24.19 m 58.39 – 49.37 m

24.03 – 33.29 m 49.53 – 40.27 m

32.20 – 40.80 m 41.36 – 32.76 m

40.69 – 49.90 m 32.87 – 23.66 m

T-51 7

22.29 – 28.36 m 56.71 – 52.72 m

16.29 – 19.07 m 60.64 – 58.82 m

34.39 – 48.01 m 48.77 – 39.83 m

43.48 – 57.05 m 42.80 – 33.90 m

55.56 – 69.23 m 34.88 – 25.91 m

69.16 – 75.28 m 25.96 – 21.94 m

73.73 – 84.40 m 22.96 – 15.96 m

T-52 7

36.51 – 46.90 m 46.74 – 39.79 m

45.54 – 59.06 m 40.70 – 31.65 m

71.26 – 58.96 m 23.49 – 31.72 m

71.22 – 83.32 m 23.51 – 15.42 m

77.58 – 83.32 m 19.26 – 15.42 m

73.48 – 78.00 m 22.00 – 18.98 m

68.48 – 73.00 m 25.35 – 22.32 m


April 2011 Report No. 10-1121-0222 11

Groundwater levels were measured on January 20, 2011 and in situ rising head permeability tests were carried

out between July 26 and August 11, 2010 in the monitoring wells installed in the bedrock in boreholes T-5, T-10,

and T-13 during Stage 1 and in T-35 on December 16, 2010 during Stage 2.

In-situ rising head tests were also carried out in the overburden wells at borehole T-12 (advanced during Stage

1) on July 29 and 30, 2010 and in the overburden monitoring wells installed in boreholes W-058, W-060 and W-

062 (advanced during Stage 2) between December 6 and 21, 2010.

Water level dataloggers were installed in each of the monitoring wells to record daily water levels.

3.1.3 Geotechnical Logging

3.1.3.1 Soil Logging

The following geotechnical parameters were routinely recorded as part of the soil geotechnical logging:

Soil constituents;

Standard Penetration Test (SPT) Values; and,

Field Vane Shear Test Values.

The density index for cohesionless soils is estimated based on the SPT N-values as shown in Table 3-3 below.

Table 3-3: Density Index (CFEM, 2006)

Cohesionless Soils

N Value (Blows / FT) Density Index0 – 4 Very Loose

4 – 10 Loose

10 – 30 Compact

30 – 50 Dense

Over 50 Very Dense

The in situ consistency of cohesive soils is estimated based on the results of the field vane shear testing as

indicated in Table 3-4 below.

Table 3-4: Consistency of Cohesive Soils (CFEM, 2006)

Cohesive Soils

Undrained Shear Strength (KPA) Consistency0 – 12 Very soft

12 – 25 Soft

25 – 50 Firm

50 – 100 Stiff

100 – 200 Very Stiff

Over 200 Hard


April 2011 Report No. 10-1121-0222 12

The sensitivity of cohesive soils is described as indicated in Table 3-5 below.

Table 3-5: Sensitivity Descriptions of Cohesive Soils (CFEM, 2006)

Cohesive Soils

Sensitivity Description< 2 Low sensitivity

2 to 4 Medium sensitivity

4 to 8 Sensitive

8 to 16 Extra-sensitive

> 16 Quick

The constituents’ classification for the additional soil components are provided in Table 3-6 below.

Table 3-6: Soil Constituents (CFEM, 2006)

Percentage Classification Category Example

0 – 10 Trace Minor Constituents

Trace silt

10 – 30 Some Some gravel

30 – 50 “y” ending Major Constituents

Silty sand

= 50 And Sand and Gravel

The presence of cobbles and/or boulders is generally inferred from driving resistance, auger reaction and

scraping noises. The proportion of cobbles and boulders is therefore unknown and the term “with cobbles and

boulders” is used to describe a deposit indicating an unknown amount of cobbles and/or boulders is present.

Further detail is provided in the List of Abbreviations and Symbols in Appendix B.

3.1.3.2 Rock Logging

The following geotechnical parameters were routinely recorded as part of the geotechnical logging:

Rock Type and Geotechnical Description;

Total Core Recovery (TCR);

Solid Core Recovery (SCR);

Rock Quality Designation (RQD);

Fractures per 0.25 metre;

Weathering Classification;

Hardness;

Major Structures;

Discontinuity Type;

Discontinuity Dip; and,

Discontinuity Properties.


April 2011 Report No. 10-1121-0222 13

Total Core Recovery (TCR) is the total length of core recovered expressed as a percentage of the measured

length drilled for each core run.

Solid Core Recovery (SCR) is estimated by measuring the cumulative length of solid core, recovered at full

diameter and is expressed as a percentage of the total length drilled.

Rock Quality Designation (RQD) is defined as the percentage of core recovered from hard, sound pieces of core

which are 100 millimetres (mm) or more in length for the total length drilled. The RQD does not include core with

an unconfined compressive strength of less than 1 MPa or mechanical breaks in the core. The RQD value is

calculated after Deere and Deere (1988) and defined as:

RQD (%) = 100 x length of hard, sound core in pieces 100 mm or longer

length of core run

Natural fractures were measured at 0.25 metre increments for each core run. Values of fracture frequency,

expressed as the number of fractures per metre, were subsequently calculated.

The hardness scale shown on Table 3-7, which is based on the International Society of Rock Mechanics (ISRM)

guidelines, was used for field estimation of the intact rock strength during field mapping and geotechnical core

logging.

Table 3-7: Estimation of Rock Hardness (ISRM, 1981)

Grade Description Field Identification Approx.

UCS Range (MPa)

R0 Extremely weak rock Indented by thumbnail. 0.25 – 1

R1 Very weak rock Material can be shaped with a pocket knife or can be peeled by a pocket knife. Crumbles under firm blows of pick (or point) of geological hammer.

1.0 – 5.0

R2 Weak rock

Knife cuts material but too hard to shape into triaxial specimens or material can be peeled by a pocket knife with difficulty. Shallow indentations (< 5 mm) made by firm blow with pick (or point) of geological hammer.

5.0 – 25

R3 Medium strong rock

Cannot be scraped or peeled with a pocket knife. Hand held specimens can be fractured with single firm blow of geological hammer.

25 – 50

R4 Strong rock Hand held specimen requires more than one blow of geological hammer to fracture it.

50 – 100

R5 Very strong rock Specimen requires many blows of geological hammer to break intact rock specimens (or to fracture it).

100 – 250

R6 Extremely strong rock Specimen can only be chipped under repeated hammer blows, rings when hit.

> 250

The degree of weathering and/or alteration was recorded on a per core run basis during the geotechnical core

logging. The weathering process describes the breakdown of rock by physical process, while the hydrothermal

and/or supergene alteration processes cause the alteration and breakdown of the intact rock by chemical

processes. The degree of weathering or alteration tends to cause a reduction in the rock strength and

competency.


April 2011 Report No. 10-1121-0222 14

Table 3-8 was used to describe the degree of weathering as defined by the ISRM (1981). It provides a

qualitative measure of the degree of weathering for the original rock material. The same table was adopted to

define the degree of alteration of the rock.

Table 3-8: Weathering Classification (after ISRM 1981)

Term Symbol Description Discoloration

Extent Fracture

Condition Surface

Characteristics

Residual soil

W6

All rock material is converted to soil. The mass structure and material fabric are destroyed. There is a large change in volume, but the soil has not been significantly transported.

Throughout N/A Resembles soil

Completely weathered

W5

100% of rock material is decomposed and/or disintegrated to soil. The original mass structure is still largely intact.

Throughout Filled with alteration minerals

Resembles soil

Highly weathered

W4

More than 50% of the rock material is decomposed and/or disintegrated to a soil. Fresh or discoloured rock is present either as a discontinuous framework or as corestones.

Throughout Filled with alteration minerals

Friable and possibly pitted

Moderately weathered

W3

Less than 50% of the rock material is decomposed and/or disintegrated to a soil. Fresh or discoloured rock is present either as a discontinuous framework or as corestones. Visible texture of the host rock still preserved. Surface planes are weathered (oxidized or carbonate filling) even when breaking the “intact rock”.

>20% of fracture

spacing on both sides of

fracture

Discoloured, may contain thick filling

Partial to complete discoloration, not friable except poorly cemented rocks

Slightly weathered

W2

Discoloration indicates weathering of rock material on discontinuity surfaces (usually oxidized). Less than 5% of rock mass altered.

<20% of fracture

spacing on both sides of

fracture

Discoloured, may contain thin filling

Partial discoloration

Fresh W1 No visible sign of rock material weathering.

None Closed or discoloured

Unchanged


April 2011 Report No. 10-1121-0222 15

Any major geological structures encountered during drilling were logged. Where fracture zones or broken core

were encountered, dip angles were taken along the contacts of the structure. The following major structure

identifications were used:

Fault (FLT) – Natural break with displacement evident. Typically consists of a zone of generally greater

than 0.5 m of altered, weak and typically clay gouge and/or crushed and/or broken rock. Extensional faults

were also noted as smaller zones of healed breccia material, with a slight discoloration and alteration and

carbonate veining.

Shear (SH) – Natural break with displacement evident. Typically consisted of a series of tightly spaced

joints/fractures, slickensides, and possibly folded and healed relic rock fabric. The discontinuities

associated with the shears would be noticeably more altered than those in the surrounding rock. This is

commonly seen in weaker argillaceous seams found between more competent limestones.

Fracture Zone (FZ) – Small zone of broken rock fragments, possibly in combination with slightly weaker or

altered material. A network of joints and/or fractures is associated with this zone that likely broke further

due to drilling processes.

Broken Core (BC) – Small zones of broken rock fragments, possibly in combination with slightly weaker

material. There would not be a trend of fractures associated with the broken core and the broken core may

have resulted from the drilling process.

All natural discontinuities were described and their dip angle measured. The following types of discontinuities

were identified:

Bedding (BD) – If the rock fabric showed a preferential trend in stratigraphic layering, the discontinuities

associated with this trend were identified. The designation HBD for “healed” bedding was used to

represent bedding that was not broken.

Joint (JN) – This type of discontinuity shows; persistence, full separation, some aperture, and typically

some form of staining, alteration, coating or infill. A joint would typically be associated with the major and

minor joint sets within the rock mass structural domain. Occasionally a healed joint was identified and

denoted as HJN.

Vein (VN) – Typically formed of calcite (carbonate) seams. The designation HVN was used for veins that

were not broken, i.e., “healed”.

Fracture (FR) – Not a mechanical break, but a discontinuity likely broken during drilling which follows a

previously healed discontinuity feature, or trend of weakness. The fractures were typically tight, with clean

to some alteration along the surfaces. The fractures were often not completely broken, with jagged contact

surfaces, which likely broke along a preferential plane associated with a weakness trend such as a healed

joint.

Contact (CO) – A discontinuity formed by a contact between different rock types, or a rock type and an

intrusive. The designation HCO represents healed contact boundaries.


April 2011 Report No. 10-1121-0222 16

The surface conditions of the logged discontinuities were described using the parameters Joint Roughness (Jr)

and Joint Alteration (Ja), from the Barton et al. (1974) Q system of classification. The values assigned for

logging Jr and Ja are shown in Table 3-9 and Table 3-10, respectively.

Table 3-9: Joint Roughness, Jr (after Barton et al. 1974)

Description Jr

Rough and wavy 3.0

Smooth and wavy 2.0

Rough and planar 1.5

Smooth/planar/filled 1.0

Slickensided/planar 0.5

Table 3-10: Joint Alteration, Ja (after Barton et al. 1974)

Unfilled or Coated Joints Filled

Description Ja Description Ja

Clean/staining only – either fresh rock or discoloration of discontinuity. The physical appearance and texture of the host rock is unaltered.

1

Stiff clay (<5 mm) – includes filling with stiff clay material such as chlorite/talc/epidote (>1 mm). No rock on rock contact, little frictional resistance (Jr=1).

6

Slightly altered – includes slight oxidation, slight carbonate/clay/pyrite alteration. The majority of rock texture (roughness) is still visible, and discontinuities show good rock on rock contact, although with slightly lower material contact strengths.

2

Soft clay (<5 mm) – soft filling (low friction material) includes >1 mm of soft (altered minerals) such as chlorite/talc/epidote. No rock on rock contact. No frictional resistance, and low cohesive strength (Jr=1).

8

Sandy/silty coatings – includes physical sand/silt materials, and harder mineral materials such as calcite/carbonate. Less than 1 mm of coating covering the majority of the joint face. Material can typically be wiped off with finger or peeled with knife (carbonates). Discontinuity will still show relatively good roughness with majority rock/rock contact.

3

Hydrating clays (<5 mm) – filling of material which is very soft when saturated (“soupy”). No frictional resistance and little to no cohesive strength (Jr=1).

12

Soft mineral coatings (<1 mm) – includes thin coating of clay/talc over the majority of the joint face. The coating will visibly decrease the roughness of the joint face, however the material would still show reasonable frictional characteristics.

4

Soft Clays / Low Friction (> 5mm) – soft filling (low friction material) includes >1 mm of soft (altered minerals) such as chlorite/talc/epidote. No rock on rock contact. No frictional resistance, and low cohesive strength

15

Sand/crushed rock (>1 mm) – continuous filling of sand and crushed rock material (altered or otherwise) which completely covers joint face, with loss of rock on rock contact reducing frictional strength of joint (Jr=1).

5

Hydrating Clays/Chlorite (> 5mm) - filling of material which is very soft when saturated (“soupy”). No frictional resistance and little to no cohesive strength

20

The conditions along the joint surface of a discontinuity, recorded in order to assess the strength and behaviour

of the discontinuity, were also recorded using the Bieniawski RMR76 system.


April 2011 Report No. 10-1121-0222 17

According to the Bieniawski criteria, the general condition of the discontinuities or series of discontinuities within

a recorded interval are assigned a particular value according to their roughness, continuity, aperture, alteration,

and infill. A Joint Condition (Jcon) value is assigned according to Table 3-11.

Table 3-11: Joint Condition, Jcon (after Bieniawski 1976)

Fracture Condition RMR76

Very rough surfaces, fractures not continuous, no separation, unweathered. 25

Slightly rough surfaces, separation < 1 mm, slightly weathered. 20

Slightly rough surfaces, separation < 1 mm, highly weathered. 12

Slickensided surfaces OR Gouge < 5 mm thick OR Separation = 1-5 mm Continuous fractures. 6

Soft gouge > 5 mm thick OR Separation > 5 mm. Continuous fractures. 0

3.2 Borehole Geophysical Logging 3.2.1 Methodology

The geophysical logging of the bedrock boreholes was performed to collect information on the geological

structure and hydrogeological characteristics of the overburden and rockmass.

There were three different suites of logs performed, which are summarized in the following table:

Table 3-12: Summary of Geophysical Logging Suites

Purpose Full Suite Partial Suite

Stratigraphy Natural Gamma

Apparent Conductivity Natural Gamma

Apparent Conductivity

Structure and Engineering Properties

Acoustic Televiewer Optical Televiewer Mechanical Calliper

Hydrogeophysics Fluid Temperature

Fluid Resistivity Heat Pulse Flow Meter

Note:

1) The hydrogeophysical testing, when carried out, was conducted under both ambient and pumping conditions when possible, to stress the well.

For the full suite logging (typically carried out in rock drillholes) the boreholes were cased to the bedrock surface

and open below. For the partial suite logging typically carried out in overburden boreholes, the boreholes were

uncased and PVC lined.

Descriptions of each geophysical probe are described below:

Natural Gamma

The natural gamma log provides a measurement (recorded in counts per second – cps) that is proportional to

the natural radioactivity of the formation. The sample volume for the γn log is typically a 25 to 30 centimetre (cm)

radius. The log is used principally for lithologic identification and stratigraphic correlation.


April 2011 Report No. 10-1121-0222 18

The tool used for logging employs a scintillation NaI detector. The gamma–emitting radio-isotopes that naturally

occur in geologic materials are Potassium 40 and nuclides in the Uranium 238 and Thorium 232 decay series.

Potassium 40 occurs with all potassium minerals including potassium feldspars. Uranium 238 is typically

associated with dark shale’s and uranium mineralization. Thorium 232 is typically associated with biotite,

sphene, zircon and other heavy minerals.

Apparent Conductivity

This measurement records the apparent conductivity of the rock or soil mass surrounding the borehole using the

inductive electromagnetic technique. The probe provides a radial bulk measurement of the material 0.1 metre to

1.0 metre from the borehole wall over a distance of 1.0 metre. The measurement is unaffected by conductive

borehole fluid or the presence of plastic casing. This log is generally used in conjunction with the natural gamma

log to identify variations in lithology/stratigraphy.

Mechanical Calliper

This measurement records the borehole diameter as indicated by the average deflection of three spring-loaded

arms pressed against the wall of the borehole. Abrupt shifts to larger diameter (kicks) can indicate the locations

where fractures intersect the borehole wall. However, the thickness of the calliper arms and the mechanical

enlargement of fractures that can occur during drilling result in an approximate, qualitative relation between

fracture aperture and the size of the calliper deflection. Changes in borehole diameter indicated by the calliper

log complement other geophysical logs – e.g., accurate changes in borehole diameter are needed for

interpretation of structure from acoustic and optical televiewer logs.

Acoustic Televiewer

This measurement produces an image of the pattern of reflection of an ultrasonic pulse from a source that scans

the borehole wall as the logging probe is slowly moved along the borehole. The televiewer probe also records

telemetry so that the azimuth of the scan and the deviation of the borehole can be measured during logging.

The reflection is uniformly bright wherever the borehole wall is solid and smooth. The reflected pulses are

scattered wherever a fracture or other irregular opening intersects the borehole wall. Strike and dip are

determined by matching a template to the apparent shape of a fracture. The accuracy of this measurement

depends on the degree to which the shape of the feature represents that predicted for a planar feature and by

the degree of damage and/or erosion during the drilling process associated with the point where the fracture

intersects the borehole wall.

Optical Televiewer

This measurement produces a continuous, oriented 360° image of the borehole wall using an optical imaging

system as the logging probe is slowly moved along the borehole. The televiewer probe is magnetically

orientated so that the azimuth of the scan and the deviation of the borehole can be measured during logging.

The orientation of structure intersect in the borehole is determined in the same way as for the acoustic

televiewer.

Fluid Column Temperature and Resistivity

This measurement records the temperature and resistivity of the fluid filling the borehole. These measurements

apply to the fluid (water) in the borehole and may not be the same as the temperature and resistivity of the rocks

surrounding the borehole. The characteristics of these measurements (changes in slope or abrupt shifts in

values) can often be related to flow in the borehole at the time of logging. This measurement was recorded


April 2011 Report No. 10-1121-0222 19

under ambient (static) and dynamic (steady-state pumping) conditions when possible to better characterize the

hydrogeological characteristics in the vicinity of the borehole.

Heat Pulse Flowmeter

This measurement records the vertical flow at a given depth in the borehole when the probe is held stationary

long enough to eliminate the effects of probe movement on the fluid column. The measurement gives the time

required for vertical flow to move a thermally tagged parcel of water a distance of 2 cm up or down borehole after

heating by capacitor discharge onto an electrical grid. The probe measures flow through a cylindrical

measurement section where the borehole annulus surrounding this cylinder is blocked by a flexible disk (the

diverter). Flowmeter response times are converted to flow rates using calibration formulas provided by the probe

manufacturer. Two flow profiles were made, under ambient conditions first, and then under steady pumping

conditions. The heat-pulse flowmeter has a low flow detection limit of about 0.01 gpm (0.038 L/min). The device

also has an upper flow detection limit associated with the thermal inertia of the thermistors, which cannot

respond quickly enough to detect flow if the flow exceeds about 1.5 gpm (5.68 L/min) in either direction

(up or down).

3.2.2 Geophysical Logging Procedure

The following table indicates the geophysical logging techniques that were carried out in each of the boreholes

for this investigation:

Table 3-13: Summary of Geophysical Logging for Each Borehole

Borehole

No. Geophysical Logging

T-1 Full suite completed.


T-3 No dynamic fluid column temperature and resistivity or ambient heatpulse flow metering due to low water table. Remainder of full suite completed.




T-7 No dynamic fluid column temperature and resistivity or ambient heatpulse flow metering due to low water table. Remainder of full suite completed.




T-11 Full Suite completed.

T-12 Gamma conductivity only.


T-14 Optical televiewer to 17 m only (image obscured below). An attempt was made to flush the drillhole to clear the field of view but no return was achieved (~5000 L pumped into drillhole). Remainder of full suite completed.




April 2011 Report No. 10-1121-0222 20

Borehole

No. Geophysical Logging

T-35A Full suite completed.








T-47 No fluid thermal resistivity or heat pulse flow meter.

T-51 Optical televiewer image obscured. Unable to clear hole. Remainder of full suite completed.


W-061 No mechanical calliper.

W-062 No mechanical calliper.

3.3 In Situ Stress Measurements Hydraulic fracturing (hydrofracturing) stress measurements were carried out in Boreholes T-41, T-44 and T-48

between November 15th and 19th 2010. The boreholes used in this testing were drilled at a diameter of 96 mm

(HQ3) by Downing using wireline coring equipment. The measurements followed the ASTM test procedure for

hydraulic fracturing stress measurements, ASTM D 4645-87 (Standard Test Method for Determination of the In-

Situ Stress in Rock Using the Hydraulic Fracturing Method). The testing consisted of two parts, fracture

generation and fracture orientation. The hydrofracturing testing results are presented in Section 7.4 and

procedures and theoretical background are presented in detail in Appendix F.

3.4 Geological Mapping Geological field mapping was carried out by Golder Associates in the downtown Ottawa region on April 7 and 8,

2010. Due to the urban setting of this project, there were a limited amount of bedrock exposures within close

proximity to the proposed tunnel alignment. The 4 sites that were structurally mapped are shown on Figure 3.1.

Geological mapping included descriptions of the lithology, measurements of the orientation of major joint sets,

descriptions of the joint characteristics and notes on groundwater seepage. The geological mapping data is

presented in Section 6.2.


April 2011 Report No. 10-1121-0222 21

4.0 LABORATORY TESTING Laboratory testing carried out on the rock core samples included unconfined compressive strength (UCS) (ASTM

D 2938), Brazilian tensile (ASTM D 3967), direct shear, triaxial, point load, Cerchar abrasion (Colorado School of

Mines standard), Taber abrasion, Shore hardness, Punch penetration, drillability (SINTEF standard),

petrographic analyses, swelling and whole rock analyses. Whole rock analyses is an X-Ray fluorescence

spectroscopy to determine a sample’s mineral composition of SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, Cr2O3,

MnO, TiO2, P2O5, V2O5 and LOI. A suite of abrasion and drillability testing on Lindsay and Verulam rock

samples from within the tunnel horizon (i.e., between about the tunnel obvert and invert) were performed to

provide a measure of the brittleness, rock abrasivity and strength for determining cutter wear rate and costs.

Tests include the following: Cerchar abrasion, Taber abrasion, Shore abrasion, Punch penetration, Moh’s

hardness and drillability testing. Drillability testing includes Brittleness Value (S20), Sievers' J-Value (SJ),

Abrasion Value (AV) and Abrasion Value Cutter Steel (AVS).

Testing carried out on the soil samples included moisture contents (ASTM D 4643), Atterberg limits (ASTM

4318), grain size analyses (ASTM D 422) and hydrometers.

Table 4-1 summarizes the number of soil and rock laboratory tests completed from the Stage 1 and 2 tunnel

borehole investigation program. Results of all laboratory testing are included in Appendix E.

Table 4-1: Summary of Laboratory Tests

Bo

reh

ole

N

o.

Wat

er

Co

nte

nt

Att

erb

erg

L

imit

s

Sie

ve &

H

ydro

met

er

UC

S

Bra

zilia

n

Ten

sile

Tri

axia

l (R

ock

)

Dir

ect

Sh

ear

Po

int

Lo

ad

Cer

char

A

bra

sio

n

Tab

er

Ab

rasi

on

Sh

ore

H

ard

nes

s

Pu

nch

P

enet

rati

on

Dri

llab

ility

Wh

ole

Ro

ck

An

alys

is

Pet

rog

rap

hy

T-1 1 14

T-2 1 2 1 1 1 1 1

T-3 1 2 1 1 1 1 1

T-4 2 1 22

T-5 2 2 1 1 1 1 1

T-6 2 19

T-7 29 1 1

T-8 2 2 1 1 1 1 1 1

T-9 1

T-10

T-11 2 2 15

T-12 3 3 6

T-13 16

T-14 2 2 2 2 17 1 1 1 1

T-15 2 2 15

T-16 2 2 2 1 1 1

T-35 3 3 3

T-35A 3 2

T-36 3 2 3 3 2 12 1


April 2011 Report No. 10-1121-0222 22

Bo

reh

ole

N

o.

Wat

er

Co

nte

nt

Att

erb

erg

L

imit

s

Sie

ve &

H

ydro

met

er

UC

S

Bra

zilia

n

Ten

sile

Tri

axia

l (R

ock

)

Dir

ect

Sh

ear

Po

int

Lo

ad

Cer

char

A

bra

sio

n

Tab

er

Ab

rasi

on

Sh

ore

H

ard

nes

s

Pu

nch

P

enet

rati

on

Dri

llab

ility

Wh

ole

Ro

ck

An

alys

is

Pet

rog

rap

hy

T-39 3 2 1

T-40 7 2 7

T-41 3 2 2 20

T-42 3 1 2

T-43 3 2 1 19

T-44 3 2 1 20 1 1 1

T-46 3 2 1 2 28

T-47 1 1 2 2 1 16 1

T-48 3 1 20 1

T-51 3 2 1 1

T-52 2 2 1 1 1

T-53 9 2 9

W-057 1 1

W-058 2 2 1 1 4

W-059 2 2

W-060 1 1 2 2 4

W-061 2 2 2 1

W-062 1 1 2 1 8

Total 39 16 38 58 40 6 10 298 12 6 6 7 2 6 2


April 2011 Report No. 10-1121-0222 23

5.0 REGIONAL GEOLOGY 5.1 General The study area for this assignment lies within the minor physiographic region known as the Ottawa Valley Clay

Plain, which lies within the major physiographic region of the Ottawa-St. Lawrence Lowland, as delineated in The

Physiography of Southern Ontario (Chapman and Putnam, 1984).

The Ottawa Valley Clay Plain region is characterized by relatively thick deposits of sensitive marine clay, silt and

silty clay that were deposited within the Champlain Sea basin. These deposits, known as the Champlain Sea

clay or Leda clay, overlie relatively thin, commonly reworked glacial till and glaciofluvial deposits, that in turn

overlie bedrock. This region is underlain by a series of sedimentary rocks, consisting of shales, limestones,

dolostones and sandstones that are, in turn, underlain by igneous and metamorphic bedrock of the Precambrian

Shield.

Based on the Geological Survey of Canada mapping (see Figure 3.1), there are several main geological units

found across the proposed tunnel alignment: the Bobcaygeon, Verulam, Lindsay, Billings and the Carlsbad

formations. The Bobcaygeon formation of Middle Ordovician age is characterized by interbedded light to dark

grey to brownish grey, lithographic to coarsely crystalline, fossiliferous limestone with shaly partings.

The Verulam formation of Middle Ordovician age is characterized by thinly to medium bedded, fine grained, grey,

crystalline, weak to very strong limestone interbedded with shale seams. The most widespread unit across the

project area is the Lindsay formation of Middle to Upper Ordovician age. This unit in the Ottawa region is

characterized by argillaceous, nodular, very fossiliferous, fine to coarse grained limestone. Conformably

overlying the Lindsay formation is the Billings formation of Upper Ordovician age, which consists of a dark brown

to black, moderately fossiliferous, slightly calcareous to non-calcareous shale with interbeds of dark grey

limestone. Fossils in the Billings formation are often pyritized. Gradationally superseding the Billings formation is

the Carlsbad formation of Upper Ordovician age. This unit is characterized by dark grey, interbedded,

calcareous and non-calcareous shale, fossiliferous siltstone and medium to pale grey, bioclastic limestone.

Cross-bedding, flute casts and ripple marks are typically observed in the Carlsbad formation (Belanger, 1988).

The Geological Survey of Canada bedrock geology map does not accurately reflect the rock types encountered

during the drilling completed to date. Where the rock formation could be identified based on the geophysics

surveys and lithologic description, it is noted on the drillhole logs. Figure 6.1 presents the surficial rock type

lithologic boundaries based on the encountered rock formations and previous experience.

5.2 Regional Tectonic and Seismic Setting The project site falls within the Western Quebec Seismic Zone (WQSZ) according to the Geological Survey of

Canada. The WQSZ constitutes a large area that extends from Montreal to Témiscaming, and which

encompasses the Ottawa area. Within the WQSZ recent seismic activity has been concentrated in two

subzones; one along the Ottawa River and another more active subzone along the Montreal-Maniwaki axis.

Historical seismicity within the WQSZ from 1900 to 2001 is given on Figure 5.1 and includes the 1935

Témiscaming event which had a magnitude (i.e., a measure of the intensity of the earthquake) of 6.2 and the

1944 Cornwall-Massena event which had a magnitude of 5.6. The most recent significant earthquake in the

Ottawa area, on June 23, 2010, had a magnitude of 5.0 and was centered about 8 km east of Val-des-Bois,

Quebec. In comparison to other seismically active areas in the world (e.g., California, Japan, New Zealand), the

frequency of earthquake activity within the WQSZ is significantly lower but there still exists the potential for

significant earthquake events to be generated.


April 2011 Report No. 10-1121-0222 24

6.0 MAJOR GEOLOGICAL STRUCTURES

6.1 Faulting As a consequence of the re-interpretation of the stratigraphy and structural geology of the Ottawa area by the

Ontario Geological Survey, principally, Williams (1991) significant variation in the locations of inferred faulting

now exists when the older published mapping is compared with the more recent publications. Although, from a

regional perspective, there is general agreement that the area of the proposed tunnel will be dissected by

several splays off the NW-trending Gloucester Fault, the actual positions of the various faults postulated by the

variety of authors over the years differ markedly. This apparent discrepancy between previous mappings has

partly resulted from differences in stratigraphic interpretation and partly from the fact that the faults themselves

are generally concealed beneath the overburden or the downtown infrastructure, such that their plan positions

have only been inferred, based on evidence of down-dragged adjacent rocks in some locations.

The available geological information suggests that the Gloucester Fault, which is the main fault of the area with a

maximum reported throw at about the centre of its length of about 550 metres according to Wilson (1946), has

spawned a series of secondary splay faults. The latest mapping, by Williams et al (1984), suggests that the

Gloucester Fault is in fact a graben structure, centred along the CP rail track alignment and the Dows Lake area

(approximately 2 km south of the OLRT tunnel alignment), and flanked on the west and east by NW and NE

trending secondary faults.

The main fault throw is inferred to occur on the westernmost plane of the graben. Across this plane, west of the

fault, Ottawa formation limestones of the Rockland and Hull Groups, now named the Bobcaygeon formation, are

downthrown against Lindsay formation limestones which exist on the east, upthrown side. These upthrown

rocks (specifically the Lower Member of the Lindsay formation, which is equivalent to Wilson's Ottawa formation)

are well exposed along the railway track in the Dows Lake area. Evidence for the westwardly trending splay

faults inferred by Williams (1991) is derived from the Transitway and parkway excavation cuts, which reveal a

number of faults trending between 135° and 145°. The westernmost of these splay faults, which offsets rocks of

the Gull River formation, is mapped immediately north of Churchill Avenue (approximately 5 km west of the

OLRT tunnel alignment), the second splay fault mapped to the immediate south of Parkdale Avenue

(approximately 3 km west of the OLRT tunnel alignment), is reported by Williams (1991) as a 20 metre wide fault

zone striking 145° that separates the Gull River, to the South-West from the Bobcaygeon to the northeast.

Further east along the Transitway, east of Stonehurst Avenue and in the Ottawa River Parkway Road cut

immediately east of Parkdale Avenue, a third splay fault is mapped within the Bobcaygeon formation. This also

comprises a zone rather than an individual shear, which Williams reports as at least 10 metres wide; also

trending at 145°. Williams also reports two other westerly trending splay faults in the Parkway roadcut within

Bobcaygeon formation rocks. These he reports to be up to 4 metre wide and striking 140° and 145°.

The Gloucester faults are NW to SE trending faults cross the proposed tunnel alignment between Lyon Street

and O’Conner Street and generally strike east – west at this location.

Stratigraphic correlation between boreholes has been undertaken by making use of the natural gamma and

apparent conductivity geophysical data. The apparent conductivity measurement records the apparent

conductivity of the rock or soil mass surrounding the borehole using the inductive electromagnetic technique.

Both the natural gamma and the apparent conductivity logs provide valuable information on formation contacts

and “marker” beds which can be used to more consistently determine the boundaries between transitional

formational contacts.


April 2011 Report No. 10-1121-0222 25

Approximately 6 faults, or sets of faults, are inferred from the Stage 1 and Stage 2 OLRT borehole investigation

as noted on Figures 6.1 and 6.2A to 6.2D. The precise fault locations between boreholes and fault orientations

are not currently known as a limited number of faults were intersected within the boreholes. The following rock

mass descriptions may not be representative of all the faults within the OLRT tunnel study area and will be

refined upon further investigations to target selected inferred fault(s) planned for spring/summer of 2011. Faults

encountered thus far within the drillholes typically comprise 0.5 m to 2.0 m wide zones of broken to crushed rock

with healed calcite veining and some gouge material comprising sand and silt size material. Bedrock quality in

the fault zones ranges from poor to good. Faults within the Lindsay, Verulam, and Bobcaygeon formations (i.e.

mainly limestone bedrock) may in some cases be calcite headed. Faults within and/or in transitions with the

Billings formation (i.e., Rideau Canal Fault) are expected to be between 0.5 m and 2.5 m in width and filled with

sand and silt size broken, weathered shale rock. In the vicinity of the faults, the bedrock is also expected to be

more fractured. This appears to be especially true near the deep bedrock valley east of Rideau Station where

the RQD values decrease significantly near the valley walls.

Vertical throws listed below are based on off-sets in the geological units measured in the downhole geophysics

logs.

Fault(s) crosses the tunnel alignment between T-2 and T-3 east of the West Portal with a vertical throw of

approximately 10 m.

Fault(s) crosses the tunnel alignment between T-46 and T-8 at the Downtown East Station with a vertical

throw of approximately 9 m.

Fault(s) crosses the tunnel alignment between T-44 and T-9 east of the Downtown East Station with a

vertical throw of approximately 4 m.

Fault(s) located between boreholes T-9 and T-43 near the east end of the Downtown East Station with a

vertical throw of approximately 25 m.

Fault(s) located between boreholes T-42 and T-41 with a vertical throw of approximately 4 m.

Fault(s) located at T-12 at the east of the Rideau Station with an undetermined vertical throw.

6.2 Bedding and Discontinuity Sets For most of the tunnel alignment, the rocks are anticipated to be flat lying to gently dipping, although zones of

local folding are evident. In general, the limestone is medium bedded, but occasionally thinly to thickly bedded

horizons exist with thin shale partings and interbeds.

6.2.1 Geological Mapping

Geological mapping of bedrock exposures in the downtown area was carried out at four sites located within the

Lindsay formation (refer to Figure 3.1 for locations).

Site 1: Primrose Avenue and Lorne Avenue

A bedrock cut was examined along a walkway found east of the intersection of Primrose Avenue and Lorne

Avenue. The limestone bedrock exposed is grey, fine grained, moderately to slightly weathered and medium

strong. The bedding is slightly undulating with 2 cm to 20 cm spacing. Overall, the rock mass structure appears

seamy to blocky (many intersecting discontinuity sets) with three main discontinuity sets, consisting of the sub-


April 2011 Report No. 10-1121-0222 26

horizontal bedding set and two sub-vertical joint sets striking east-west and north-south. Wedge failures are

evident on the rock face, created by the intersection of these main discontinuity sets.

Site 2: Empress Avenue and Albert Street

A rock slope was surveyed at the southeast corner of the intersection of Empress Avenue and Albert Street. This

area consisted of limestone outcrops and talus slopes, with moderate vegetation cover. The bedrock is grey, fine

grained, moderately to slightly weathered and medium strong. The bedding is slightly undulating to planar with

3 cm to 50 cm spacing. The rock mass structure is blocky (interlocked, angular blocks), due to four main

discontinuity sets, consisting of the sub-horizontal bedding set and three sub-vertical joint sets striking east-west,

northeast-southwest and north-south. Wedge failures are evident on the rock face, created by the intersection of

these main discontinuity sets.

Site 3: Wellington Street and Fleet Street

This site consists of a rock slope located east of the intersection of Wellington Street and Fleet Street. The

steep limestone cliff found here is approximately 15 m high, with Bronson Park located at the crest of the slope

and the Garden of the Provinces located at the toe of the slope. The bedrock is grey, fine grained, moderately to

slightly weathered and medium strong. The bedding is planar with 5 cm to 50 cm spacing. The rock mass

structure is blocky (well interlocked formed by three intersecting joint sets), due to three main discontinuity sets,

consisting of the sub-horizontal bedding set and two sub-vertical joint sets striking east-west and northeast-

southwest. Wedge failures are evident on the rock face, created by the intersection of these main discontinuity

sets.

Site 4: Service Road to Fairmont Chateau Laurier

This site features a rock slope located along the service road from St Patrick Street to the Fairmont Chateau

Laurier. The bedrock found along this rock slope is grey, fine grained, moderately to slightly weathered and

medium strong limestone. The bedding is planar with 3 cm to 50 cm spacing. The rock mass structure is blocky

(well interlocked formed by three intersecting joint sets), due to three main discontinuity sets, consisting of the

sub-horizontal bedding set and two sub-vertical joint sets striking east-west and north-west. A minor inclined

joint set was also noted, dipping south at approximately 30° to 40°. Many wedge failures are evident along this

rock face, created by the intersection of these main discontinuity sets. Recent fallen rock debris was noted

along the service road.

6.2.2 Mapped Structural Data

The structural data collected during the field survey is summarised in Table 6-1. There are four main

discontinuity sets found within the surveyed sites, which include a sub-horizontal bedding set (BD) and sub-

vertical joint sets (JN1 / JN1A and JN2). Wedge failures formed by the major joint sets were observed at each

site. The structural data from the geological mapping has been plotted as stereographic projections (stereoplots)

on Figures 6.3 and 6.4.


April 2011 Report No. 10-1121-0222 27

Table 6-1: Geological Mapping Structural Data

Set ID Type Dip (°)

Dip Direction

(°)

Aperture (cm)

Infilling Surface

Roughness Shape Water

Spacing (cm)

BD Bedding 2 80 0 – 1 Stained Rough Planar Damp 2 – 50

JN1 Joint 85 109 0 – 5 Stained Rough Planar Dry 2 – 300

JN1A Joint 84 144 0 – 5 Stained Rough Planar to Undulating

Dry 10 – 400

JN2 Joint 83 194 0 – 15 Stained to Coated

Rough Planar Dry to Damp

3 – 100

6.2.3 Borehole Structural Data

Structural data was collected in the boreholes using both optical and acoustic televiewer surveys as well as

oriented core measurements. The structural data from the borehole televiewer surveys and oriented core

measurements has been plotted as stereographic projections (stereoplots) on Figures 6.3 and 6.4. Contoured

stereoplots for the acoustic televiewer structural data for each borehole are plotted in Appendix G. Based on

the contoured stereoplots the rock mass structure appears to be dominated by the near horizontal limestone

bedding (BD). Furthermore, two major sub-vertical joint sets (JN1 and JN2) could be identified, running

approximately perpendicular to each other and striking north-west and north-east, respectively. The sub-vertical

minor joint set JN2A is likely a subset of the adjacent joint set JN2. In addition, three minor joint sets (JN3, JN4

and JN5), could be identified. The joint set orientations are given in the following Table 6-2:

Table 6-2: Joint Set Orientations

Set ID Type Dip (°)

Dip Direction (°)

JN1 Joint 81 305

JN2 Joint 89 022

JN2A Joint 79 052

JN3 Joint 30 216

JN4 Joint 25 050

JN5 Joint 52 000

BD Bedding 01 101

The majority of all identified joints (64%) have a rough surface, one third (31%) of the joints are smooth. Few

polished, slickensided or very rough joint surfaces were logged. The shapes of the joints are mostly undulating

(37%) or planar (29%), but some curved, irregular or stepped surfaces were also logged.

Most of the joints (55%) have slightly altered walls. Further, nine percent (9%) of the joints are clean and 16%

have stained surfaces but show no signs of alteration. A continuous coating of the joint surfaces, mostly

consisting of less than 1 mm of clay or calcite, was found in 9% of the logged joints and 11% of the joints have

an infilling of more than 1 mm consisting mainly of clay, gouge or broken rock.


April 2011 Report No. 10-1121-0222 28

Based on the acoustic televiewer stereoplots along the OLRT tunnel alignment (Appendix G), the bedding gently

dips from 5 to 20 degrees to the east-southeast. Bedding will typically steepen closer to faults.


April 2011 Report No. 10-1121-0222 29

7.0 SUBSURFACE CONDITIONS The subsurface conditions encountered in the boreholes advanced during the scoped Phase II ESA for this

project are shown on the Record of Borehole sheets in Appendix A. The subsurface conditions encountered in

the geotechnical boreholes advanced during the current investigation are shown on the Record of Borehole and

Drillhole sheets in Appendix B. Photographs of the recovered rock core from the drillholes are contained in

Appendix C. The results of the downhole geophysical logging in the bedrock are shown on the Summary Record

of Drillhole Logs with Geophysics in Appendix D.

The results of the laboratory testing on the selected soil and rock samples are given on the Record of Borehole

sheets and in Appendix E. It should be noted that soil samples were retrieved using a 50 mm diameter sampler

and therefore the results reflect only the portion of this deposit with particle size less than 50 mm.

A detailed description of the subsurface conditions encountered at each of the augerhole and borehole locations

is provided on the respective Record of Augerhole or Borehole sheets.

The following sections present an overview of the subsurface conditions encountered in the boreholes and

augerholes advanced during the current investigation.

7.1 Overburden 7.1.1 General

West Portal

The overburden within the West Portal area (boreholes W-057 to W-062, inclusive, T-1 and T-2) ranges from

about 6 to 10 m in thickness. In general, the overburden along this portion of the alignment consists of fill

(including pavement at some locations), related to underground services and/or previous uses along the

alignment, underlain by a well-graded glacial till which may be interlayered with silts and/or sands. At some

locations, the glacial till is locally overlain with relatively thin deposits of silt, sand or silty clay.

West Portal to Rideau Street

The overburden along the alignment from the West Portal to the valley in the surface of the bedrock at Rideau

Street (boreholes T-3 to T-10, T-41 to T-48, T-51, T-52, T-AB to T-AI and T-AL) ranges from about 2 to 6 m in

thickness. In general, the overburden along this portion of the alignment consists of fill (including pavement at

some locations), related to underground services and/or previous uses along the alignment, underlain by glacial

till which may be interlayered with silts and/or sands. At some locations, the glacial till is locally overlain with

relatively thin deposits of silt, sand or silty clay.

Rideau Bedrock Valley

In the vicinity of Rideau Street, just east of Sussex Drive, the surface of the bedrock is locally much deeper,

extending to depths ranging from about 15 m to greater than 37 m (boreholes T-11, T-12, T-40, T-53, and T-AK).

This ‘valley’ in the bedrock surface trends northwest-southeast and is indicated to be about 120 m in width at the

surface of the bedrock. In general, the overburden along this portion of the alignment consists of 1 to 3 m of fill

underlain by 2 to 10 m of silty clay and silt overlying 6 to 20 m of glacial till that in turn overlies bedrock. The

thick deposit of glacial till within the bedrock valley varies in consistency from silty sand / sandy silt with some

gravel and cobbles to sand with some silt and gravel. The layers of sand present within the glacial till range from

2 m to 5 m in thickness. Difficult drilling conditions were encountered while drilling with the diamond drill in


April 2011 Report No. 10-1121-0222 30

boreholes T-12 and T-40 due to the heterogeneous nature of the glacial till (boulders, cobbles, sand, silt) at

depths of 30 m.

Rideau Station to East Portal

The overburden along the alignment from east of Rideau Street to the East Portal (boreholes T-13, T-14, T-15,

T-16, T-35 and T-36) ranges from 1 m to 11 m in thickness. At Laurier Avenue, the overburden extends to

depths of about 6 m. In general, the overburden along the portion of the alignment from Laurier Avenue to the

East Portal, where the overburden was sampled, consists of fill, related to underground services and/or previous

uses along the alignment, underlain by clayey silt to silty clay which in turn overlies glacial till.

Plots of moisture content and undrained field shear strength value versus elevation are presented on Figures 7.1

and 7.2.

7.1.2 Topsoil, Pavement and Fill

Topsoil was encountered extending from the ground surface to depths ranging from about 50 to 460 mm at

boreholes W-062, T-AJ, T-35 and T-36.

Pavement consisting of asphaltic concrete and/or Portland cement concrete or brick was encountered at the

ground surface at boreholes W-057, W-059, W-060, T-3, T-4, T-7, T-9, T-11, T-12,T-14, T-15, T-16, T-40, T-41,

T-47, T-48, T-AC, T-AE, T-AF, T-AK and T-AI. The pavement ranges from about 40 to 460 mm in thickness.

Portland cement concrete, ranging from about 50 to 180 mm in thickness, was also encountered in boreholes W-

057, T-3 and T-12 within the fill at depths ranging from about 0.2 to 1.5 m below the ground surface. Brick and

mortar, about 0.8 m in thickness, was also encountered below the fill at borehole T-36 at a depth of about 0.8 m

below ground surface.

Fill was encountered underlying the topsoil, pavement material or extending from the ground surface at all the

boreholes. The fill was not penetrated at borehole T-AI but was proven to a depth of about 2.4 m. The fill at the

remaining boreholes, where sampled, extends to depths ranging from about 0.6 to 6.1 m below ground surface.

The fill at boreholes T-AD, T-AJ, T-AL and T-41 extends to the bedrock surface.

Crushed stone was encountered at borehole T-12 and T-36 underlying the asphaltic concrete and extending

from the surface at borehole T-AG. The remaining base and fill is variable in composition but generally consists

of silty sand to sand and gravel containing varying amounts of gravel, silt, clay, cobbles, boulders, wood

(boreholes W-060 and T-AD), ash (borehole W-058), glass (borehole T-AE), brick fragments (boreholes W-058,

W-061, W-062, T-AC, T-AE, T-AH and T-AK), coal (borehole T-41), asphalt pieces (boreholes W-058 and T-48),

concrete or mortar fragments (boreholes W-062, T-AC and T-AJ) and organic matter (boreholes W-057 and W-

059). A layer of limestone cobbles, about 0.5 m in thickness, was encountered underlying the fill at borehole T-

12 at a depth of about 1.5 m.

Standard penetration test ‘N’ values in the fill ranging from 6 to greater than 100 blows per 0.3 m of penetration

indicate a very loose to very dense state of packing. The higher ‘N’ values could reflect the presence of cobbles

and boulders (e.g., at borehole T-AD) rather than the state of packing of the soil matrix.


April 2011 Report No. 10-1121-0222 31

7.1.3 Silty Clay/Clayey Silt

Tunnel Alignment

A layer of silty clay was encountered underlying the fill at borehole T-AC. The silty clay is about 1.3 m in

thickness and has been weathered to a grey brown crust. Standard penetration tests carried out within the

weathered crust gave ‘N’ values of ‘weight of hammer’ and 2 blows per 0.3 m of penetration. The results of this

in situ testing indicate a firm to stiff consistency.

Bedrock Valley at Rideau Street

The fill at boreholes T-40 and T-AK and the sand layer underlying the fill at borehole T-12 are underlain by a

deposit of silty clay. Silty clay was also encountered in borehole T-53, below the unsampled hydro-excavation, at

a depth of about 2.7 m. The silty clay deposit at boreholes T-AC and T-53 and the upper portion of the deposit

at borehole T-40 have been weathered to a grey brown crust. The weathered silty clay extends to depths

ranging from about 3.7 to 4.6 m below the existing ground surface. Standard penetration tests carried out within

the weathered crust gave ‘N’ values ranging from 2 to 8 blows per 0.3 m of penetration. The results of this in situ

testing indicate a firm to very stiff consistency.

The results of a grain size distribution test on one sample of the weathered silty clay are shown on Figure E.1 in

Appendix E. The results of Atterberg limit tests on two samples of the weathered silty clay gave plasticity index

values of 26 and 56 and liquid limit values of 49 and 87 percent reflecting medium and high plasticity (see Figure

E.2 in Appendix E). The measured water content of two samples of the weathered crust was 44 and 77 percent.

Table 7-1: Summary of Silty Clay (Weathered Crust) Soil Samples in Rideau Valley

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel (%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-40 5 3.81 43.7 0 0 52 48 48.9 22.6 26.3

T-53 - 4.27 77.1 - - - - 87.3 31.7 55.6

The uppermost sand deposit at borehole T-12 is underlain by a thin deposit of silty clay/clayey silt, about 0.9 m

in thickness that extends to a depth of about 3.7 m below existing ground surface. This deposit is unweathered

and is grey in colour. The weathered crust at borehole T-40 is also underlain by unweathered silty clay/clayey

silt that extends to a depth of about 6.3 metres below the existing ground surface. The results of in-situ vane

testing in this material gave undrained shear strengths ranging from 30 to 77 kilopascals, indicating a firm to stiff

consistency. In-situ vane testing carried out on remoulded grey silty clay gave undrained shear strengths

ranging from 5 to 19 kilopascals, reflecting a sensitive material (i.e., sensitivity ratios ranging from about 4 to 6).

A plot of undrained shear strength versus elevation is given on Figure 7.1.

The results of a grain size distribution test on one sample of the unweathered clayey silt from borehole T-12 are

shown on Figure E.3 in Appendix E. The results of Atterberg limit testing gave a plasticity index value of 46 and

a liquid limit value of 70 percent reflecting high plasticity (see Figure E.4 in Appendix E). The measured water

content of one sample of the unweathered silty clay/clayey silt was 55%. A plot of the measured water content is

given on Figure 7.2.


April 2011 Report No. 10-1121-0222 32

Table 7-2: Summary of Silty Clay Soil Samples in Rideau Valley

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-12 2 3.05 54.8 0 3 47 50 69.5 23.5 46.1

East Portal

The fill at boreholes T-16, T-35 and T-36 are underlain by a deposit of silty clay. The silty clay at boreholes T-16

and T-36 and the upper portion of the deposit at borehole T-35 has been weathered to a grey brown crust.

The weathered silty clay extends to depths ranging from about 3.7 to 5.6 m below the existing ground surface.

Standard penetration tests carried out within the weathered crust gave ‘N’ values ranging from 3 to 12 blows per

0.3 m of penetration. The results of this in situ testing indicate a stiff to very stiff consistency.

The results of grain size distribution tests on two samples of the weathered silty clay are shown on Figure E.5 in

Appendix E. The results of Atterberg limit tests on two samples of the weathered silty clay gave plasticity index

values of 26 and 38 and liquid limit values of 58 and 62 percent reflecting high plasticity (see Figure E.6 in

Appendix E). The measured water content of two samples of the weathered crust were 47 and 49 percent.

Table 7-3: Summary of Silty Clay (Weathered Crust) Soil Samples at the East Portal

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-35 3 2.29 48.6 0 2 31 67 62.3 24.6 37.7

T-36 3 2.29 46.8 0 2 43 55 58.6 32.2 26.4

The weathered silty clay at boreholes T-35 and T-36 is underlain by a deposit of grey silty clay, about 6.7 and

2.1 m in thickness, respectively, that extends to depths of about 10.7 and 5.7 m below existing ground surface,

respectively. This deposit is unweathered and is grey in colour. The results of in-situ vane testing in this material

gave undrained shear strengths ranging from 49 to greater than 96 kilopascals, indicating a firm to stiff

consistency. In-situ vane testing carried out on remoulded grey silty clay gave undrained shear strengths

ranging from 4 to 24 kilopascals, reflecting a sensitive to extra-sensitive material (i.e., sensitivity ratios ranging

from about 3 to 13). A plot of undrained shear strength versus elevation is given on Figure 7.1.

The results of grain size distribution tests on one sample of the unweathered silty clay from each of boreholes

T-35 and T-36 are shown on Figure E.7 in Appendix E. The results of two Atterberg limit tests gave plasticity

index values of 38 and liquid limit values of 63 percent reflecting high plasticity (see Figure E.8 in Appendix E).

The measured water content of two samples of the unweathered silty clay ranged from 70 to 74 percent, which is

generally in excess of the liquid limit.

Table 7-4: Summary of Silty Clay Soil Samples at the East Portal

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-35 5 4.57 70.1 0 1 24 75 63 25.6 37.4

T-36 5 3.81 74.3 0 1 24 75 63.4 25.7 37.7


April 2011 Report No. 10-1121-0222 33

7.1.4 Sand and Silt


Silt deposits, containing varying amounts of gravel, sand, clay and cobbles, were encountered overlying the

glacial till at borehole T-53 and within the glacial till at borehole T-12. At borehole T-12, the silt extends from

about 5.5 to 6.7 m depth and at borehole T-53 the silt deposit extends from about 4.3 to 10.4 metres below

existing ground surface. Standard penetration N values of 11 and 18 blows per 0.3 m of penetration indicate the

deposit at borehole T-12 has a compact state of packing.

The results of grain size distribution testing on selected samples of the silt are shown on Figure E.9. The results

of one Atterberg limit test from the silt at borehole T-53 gave a plasticity index value of 4 and a liquid limit value

of 19 percent reflecting low compressibility (see Figure E.10 in Appendix E). The measured water content of

selected samples of the silts from boreholes T-12 and T-53 ranged from approximately 16 to 24 percent.

At borehole T-12, within the valley in the bedrock surface at Rideau Street, sand layers were encountered

underlying the fill and within the glacial till deposit at depth.

The silty sand layer below the fill at borehole T-12 is about 0.8 m in thickness, contains traces of organic matter,

and extends to a depth of about 2.7 m below existing ground surface.

The sand layer at depth within the glacial till deposit at the bedrock valley is about 0.6 m in thickness and

extends from a depth of about 26.2 to 26.8 m below the existing ground surface (i.e., elevations 38.0 to 37.4 m)

and contains traces of silt and gravel. One standard penetration test N value of 31 blows per 0.3 m of

penetration indicates this deposit has a dense state of packing.

At borehole T-53, three sand layers were encountered at depth within the glacial till. The sand layers range from

about 2.1 to 5.4 metres in thickness and extend intermittently from about elevation 48 m to about elevation 27 m.

The results of grain size distribution tests on selected samples of the sand deposits are provided on Figure E.11

in Appendix E.

Table 7-5: Summary of Silt Samples in Rideau Valley

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-12 4 5.49 23.5 4 12 77 7 - - -

T-53 - 5.79 19.3 0 0 79 21 19.1 14.8 4.2

T-53 - 7.32 13.2 0 0 95 5 - - -

T-53 - 8.84 16.4 0 0 83 17 - - -


April 2011 Report No. 10-1121-0222 34

Table 7-6: Summary of Sand Samples in Rideau Valley

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-12 21 26.22 - 6 82 11 1 - - -

T-53 - 16.16 8.9 22 61 15 2 - - -

T-53 - 21.04 - 0 91 9 0 - - -

T-53 - 35.97 - 0 97 3 0 - - -

East Portal

A layer of silt containing traces of clay and sand seams, about 1 m in thickness, underlies the unweathered silty

clay at borehole T-36 and a layer of silt containing some gravel, sand and clay, about 1.9 m in thickness,

underlies the unweathered silty clay at borehole T-35. The surface of the silt deposit at boreholes T-36 and T-35

was encountered at depths of about 5.7 and 8.8 m, respectively, below existing ground surface. Two standard

penetration test N values of 12 blows and greater than 50 blows per 0.3 m of penetration indicates this deposit

has a compact to dense state of packing.

The results of one grain size distribution test on a selected sample of the silt from each of borehole T-36 and T-

35 are shown on Figure E.12 in Appendix E. The results of one Atterberg limit test from the silt at borehole T-35

gave a plasticity index value of 17 and a liquid limit value of 34 percent reflecting medium compressibility (see

Figure E.13 in Appendix E). The measured water content of one sample of the silt from each of boreholes T-36

and T-35 were approximately 26 and 43 percent.

Table 7-7: Summary of Silt Samples at the East Portal

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-35 8 9.15 43.3 16 13 44 27 34.4 17.5 16.9

T-36 7 6.1 26.0 0 5 89 6 - - -

7.1.5 Glacial Till

The glacial till generally consists of a heterogeneous mixture of gravel, cobbles, and boulders in a matrix of silty

sand and sandy silt with a trace of clay.

West Portal

At the West Portal, the fill at all the boreholes is underlain by glacial till. The glacial till was not fully penetrated at

borehole W-057 but was proved to a depth of about 9.5 m. At the remaining boreholes at the west portal, the till

extends to the surface of the bedrock at depths ranging from about 5.9 to 9.8 m (i.e., about elevations 57.1 to

51.8).

The results of grain size distribution tests on selected samples of the glacial till at the west portal are shown on

Figure E.14 in Appendix E. It should be noted however that these samples were also retrieved using a 50 mm

diameter sampler and therefore the results reflect only the portion of this deposit with particle size less than


April 2011 Report No. 10-1121-0222 35

50 mm. The measured water content of selected samples of the glacial till ranged from approximately 6 to 19

percent.

Table 7-8: Summary of Glacial Till Samples at the West Portal

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

W-057 3 2.29 5.6 33 36 28 3 - - -

W-058 4 3.05 12.1 3 42 55 0 - - -

W-058 8 6.1 5.5 22 49 24 5 - - -

W-059 4 3.05 7.8 21 38 36 5 - - -

W-059 11 8.38 15.1 3 21 64 12 - - -

W-060 5 3.81 18.8 2 44 53 1 - - -

W-061 6 3.81 8.9 7 41 48 4 - - -

W-061 9 6.1 7.9 3 39 53 5 - - -

W-062 7 5.34 6.6 3 50 28 19 - - -

Tunnel Alignment

Glacial till underlies the weathered silty clay at borehole T-AC and the fill at boreholes T-AB, T-AE, T-AF, T-AG,

T-AH, T-47, and T-48. The glacial till was not fully penetrated in borehole T-AC but was proved to a depth of

about 5.7 m. At borehole T-AE, auger refusal was encountered within the glacial till at a depth of about 5.8 m.

Auger refusal could indicate the surface of the bedrock or it could indicate cobbles and boulders within the

glacial till. The glacial till was fully penetrated in boreholes T-AB, T-AF, T-AG, T-AH, T-47 and T-48 and varies in

thickness from about 0.8 to 3.4 m. Standard penetration test ‘N’ values for this material ranging from 1 to 37

indicate a very loose to dense state of packing. Standard penetration test ‘N’ values of greater than 100 blows

per 0.3 m of penetration were recorded but the higher ‘N’ values could reflect the presence of cobbles and

boulders, rather than the state of packing of the soil matrix.

A deposit of cobbles and boulders, that may indicate the presence of glacial till, was encountered in borehole T-5

extending from about 2.4 to 3.1 metres below existing ground surface.

The results of one grain size distribution test on a sample of the glacial till from borehole T-47 are shown on

Figure E.15 in Appendix E. It should be noted however that these samples were also retrieved using a 50 mm

diameter sampler and therefore the results reflect only the portion of this deposit with particle size less than 50

mm. The measured water content of one sample of the glacial till from borehole T-47 was approximately 7

percent.

Table 7-9: Summary of Glacial Till Sample on the Tunnel Alignment

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-47 3 4.57 6.9 35 38 23 4 - - -


April 2011 Report No. 10-1121-0222 36


At boreholes T-12, T-40 and T-53, within the valley in the bedrock surface at Rideau Street, the silty clay/clayey

silt and silt deposits are underlain by glacial till (containing silt and sand layers as discussed above). The glacial

till was fully penetrated in borehole T-12 and extends from a depth of about 3.7 m to a depth of about 34.2 m

below existing ground surface (i.e., elevations 60.5 to 30.0 m). The glacial till at boreholes T-40 and T-53 was

not fully penetrated but was proved to depths of about 30.1 and 33.2 m, respectively (i.e., elevations 34.7 and

30.9 m, respectively).

Standard penetration test ‘N’ values in this deposit ranging from 4 to greater than 100 blows per 0.3 m of

penetration, generally increasing with depth, indicate a loose to very dense state of packing. The higher ‘N’

values could reflect the presence of cobbles and boulders, rather than the state of packing of the soil matrix.

Horizons of cobbles and boulders are inferred within the Rideau Valley glacial till based on the difficult drilling

conditions and core recovery in boreholes T-40, and T-53 below a depth of 16 m.

The results of grain size distribution tests on selected samples of the glacial till from within the valley in the

surface of the bedrock at Rideau Street are shown on Figure E.16 in Appendix E. It should be noted however

that these samples were also retrieved using a 50 mm diameter sampler and therefore the results reflect only the

portion of this deposit with particle size less than 50 mm. The results of two Atterberg limit tests on the fines

portion of the glacial till at borehole T-40 gave plasticity index values of 4 and liquid limit values of 13 and 20

percent reflecting low compressibility (see Figure E.17 in Appendix E). The measured water content of selected

samples of the glacial till range from approximately 2 to 16 percent.

Table 7-10: Summary of Glacial Till Samples in Rideau Valley

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-12 16 21.04 - 9 52 26 13 - - -

T-12 20 25.61 - 14 48 27 11 - - -

T-12 23 28.2 - 18 44 25 13 - - -

T-12 26 30.48 - 8 50 29 13 - - -

T-40 6 6.21 20.0 3 17 77 3 19.6 15.7 3.9

T-40 9 8.38 9.1 0 0 81 19 - - -

T-40 12 10.6 6.9 2 42 44 12 12.6 8.8 3.8

T-40 14 12.2 9.2 15 47 29 9 - - -

T-40 16 13.72 14.1 3 19 56 22 - - -

T-40 17 14.38 7.3 34 47 16 3 - - -

T-53 - 10.37 15.8 4 14 55 27 - - -

T-53 - 11.89 14.8 2 30 43 25 - - -

T-53 - 13.11 0.7 2 15 56 27 - - -

T-53 - 14.94 14.6 4 20 56 20 - - -

T-53 - 28.96 - 8 37 37 18 - - -


April 2011 Report No. 10-1121-0222 37

Borehole No.

Sample Depth

(m)

Water Content

(%)

Gravel(%)

Sand (%)

Silt (%)

Clay (%)

LL PL PI

T-53 - 30.63 - 23 35 29 13 - - -

East Portal

Glacial till, about 0.7 m in thickness, underlies the silt at borehole T-36 at a depth of about 6.7 m below exiting

ground surface.

One standard penetration test ‘N’ value of greater than 50 blows per 0.3 m of penetration indicates a dense to

very dense state of packing. The high ‘N’ value could reflect the presence of cobbles and boulders, rather than

the state of packing of the soil matrix however.

7.2 Bedrock The bedrock in the proposed tunnel area has been described in the past as the Ottawa or Eastview formations,

but is now described principally as the Billings, Lindsay, and Verulam formations. As a result of this stratigraphic

re-zoning and altered nomenclature of the formations, considerable differences are evident in the mapped

boundaries. These formation boundary division differences can lead to considerable confusion. Figure 6.1

presents the current inferred geological boundaries between the formations from the Stage 1 and 2 drilling. The

contacts between the formations noted below are based on visual observations and the geophysics natural

gamma and conductivity logs (Appendix D). Table 7-11 summarizes the typical characteristics of the main rock

formations and sub units.

Table 7-11: Summary of Rock Formations Encountered in OLRT Study Area

Formation Rock Type Description Average Thickness

in Ottawa Area (1)(m)

Billings Shale Fresh, black, very fine grained, faintly petroliferous, very thin to thin bedded, weakly calcareous Shale.

52

Lindsay Unit 3

Shale and Limestone

Fresh interbedded sequence of black, fine grained thin to medium bedded, faintly petroliferous, calcareous Shale and medium grey, fine to medium grained, thin to medium bedded argillaceous Limestone with lesser amounts of crystalline bioclastic limestone. Shale content 50 – 90%. Transitional contact between Billings and Lindsay formation.

9

Lindsay Unit 2

Limestone

Fresh, medium to very dark grey, fine to medium grained, thin to medium bedded, fossiliferous, argillaceous, nodular textured Limestone with occasional thick bioclastic beds. Shale content 5 – 10%.

9


April 2011 Report No. 10-1121-0222 38

Formation Rock Type Description Average Thickness

in Ottawa Area (1)(m)

Lindsay Unit 1

Limestone

Fresh, dark grey, medium grained, medium to thickly bedded, nodular textured Limestone comprised of crystalline limestone nodules in wavy textured argillaceous limestone matrix. Shale content less than 1%.

10

Verulam Unit 2

Limestone

Fresh, medium to dark grey interbedded sequence of medium grained, crystalline, thin to medium bedded bioclastic and lithoclastic Limestone and very thin to thin beds of black calcareous shale. Shale content 5 to 20%.

36

Note:

1) The average formation thickness is based on the geophysical logging from the OLRT boreholes and the SWSF

proposed tunnel investigation program (Golder, 2002).

The bedrock along the proposed OLRT tunnel horizon consists mostly of limestone belonging to the Lindsay

formation (upper formation) and the underlying Verulam formation. Locally the Lindsay formation limestone is

overlaid by shale belonging to the Billings formation, usually with a transition zone of several meters between the

two formations. Drillholes within the OLRT tunnel study area encountered the lower Billings formation in the

upper five to ten meters of the bedrock between T-51 to T-9 over the Downtown East Station. Beneath the

Billings Formation, The Lindsay formation is divided into three units, Lindsay Unit 3, Lindsay Unit 2, and Lindsay

Unit 1. The upper Lindsay, Unit 3, is a transitional contact with the Billings formation and consists of Shale with

interbeds of Limestone. The results from the swelling tests on Billings shale samples from borehole T-18

indicate that the Billings formation does have a propensity to swell. The East-at-Grade Interim GDR (Golder,

2011) contains the swell test results and plots of the measured swelling stress over time. Based on the current

OLRT alignment (note that in the original alignment the Campus Station was planned to be underground), the

tunnel does not intersect the Billings Shale, but the ventilation and pedestrian access shafts will intersect the

lower Billings formation at the Downtown East Station.

7.2.1 Laboratory Testing

The following sections summarize the rock laboratory testing contained in Appendix E.

Unconfined Compressive Strength (UCS) Testing

Unconfined Compressive Strength (UCS) testing (ASTM D 2938) was completed on HQ rock core samples

above the tunnel obvert, within the tunnel limits, and below the tunnel invert based on the based on the Revision

1 Alignment dated January 17, 2011. Results of the UCS testing are listed below in Table 7-12 for the Lindsay

and Verulam formation. Partial failures were noted on several of the samples from the Verulam formation due to

failure along shale bedding.


April 2011 Report No. 10-1121-0222 39

Table 7-12: Summary of UCS Testing

Formation Test Average Range Std. Dev. No.

Tests

Lindsay Unit 3

UCS (MPa) 15.8 - - 2

E (GPa) 7.9 - - 2

Poisson’s 0.14 - - 2

Density (g/cm3) 2.58 2.54 - 2.62 - 2

Lindsay Unit 2

UCS (MPa) 71.3 65.7 - 76.9 - 3

E (GPa) 27.4 26.7 - 28.2 - 3

Poisson’s 0.14 0.13 - 0.14 - 3

Density (g/cm3) 2.68 2.67 - 2.69 - 3

Lindsay Unit 1

UCS (MPa) 80.4 62.7 - 115.7

17.6 10

E (GPa) 29.1 19.5 - 43.1 9.5 10

Poisson’s 0.15 0.10 - 0.25 0.05 10

Density (g/cm3) 2.69 2.67 - 2.72 0.01 10

Verulam Unit 2

UCS (MPa) 71.7 26.0 - 143.2

31.6 36

E (GPa) 23.9 8.1 - 70.1 13.5 36

Poisson’s 0.14 0.10 - 0.24 0.04 36

Density (g/cm3) 2.70 2.67 - 2.72 0.01 36

Notes:

1) All tests that failed along pre-existing weaknesses in the rock sample were not included in the statistics.

2) Young’s Modulus is calculated as an average slope along the linear portion of the stress-strain curve.

3) Poisson’s ratio is calculated using a circumferential extensometer during elastic deformation of the sample, i.e., the linear portion of the stress-strain curve.

4) Standard deviations are not presented for formations where the sample count was insufficient to generate a meaningful result.

Point Load Testing

Point load testing (ASTM D 5731) was completed to determine rock strength indexes every few meters along

select tunnel boreholes. Diametral and axial tests were done at each test interval to determine the strength

anisotropy. Point Load Strength Index values (Is(50)) were calculated in accordance with the recommendations of

ISRM (1981), and are summarized in Table 7.13. In this table, the corrected Is(50) values were obtained by:

50

.

Where: De is the equivalent diameter and equal to the specimen diameter (D) for the diametral

tests (or 4AD/π for the axial tests);

A is the length of the samples between the platens; and,

P is the point load applied to failure.


April 2011 Report No. 10-1121-0222 40

The point load index values suggest that within the shale (Billings formation) that the axial strength is 6 times

larger than the diametral strength and within the limestone (Lindsay and Verulam formation) the axial strength is

2 to 3 times larger due to preferential failure along horizontal bedding. The point load index (Is50) is presented in

Table 7-13 and can be correlated with the UCS.

Table 7-13: Summary of Point Load Index (Is50)

Formation Point Load Test Average (MPa) Range (MPa) Std. Dev. No. Tests

Billings Axial 5.0 3.6 – 6.4 2.0 2

Diametral 0.7 0.7 - 2

Lindsay Unit 3

Axial 5.1 1.0 - 9.3 2.5 9

Diametral 2.3 0.7 – 4.7 1.4 9

Lindsay Unit 2

Axial 7.2 2.8 – 11.0 2.6 11

Diametral 3.2 1.1 – 6.7 1.4 11

Lindsay Unit 1

Axial 6.9 1.5 – 12.3 2.6 38

Diametral 3.8 0.5 – 6.5 1.3 38

Verulam Unit 2

Axial 7.5 0.7 – 15.8 2.7 86

Diametral 3.3 0.2 – 6.9 1.5 86

Brazilian Tensile Testing

Brazilian tensile testing (ASTM D 3967) was completed on HQ rock core adjacent to UCS test samples. Results

of the tensile testing are listed in Table 7-14 below for the Lindsay and Verulam formations.

Table 7-14: Summary of Tensile Testing

Formation Average (MPa) Range (MPa) Std. Dev. No.

Tests

Lindsay Unit 3 6.5 3.8 - 9.4 - 2

Lindsay Unit 2 7.4 2.8 - 12.2 - 2

Lindsay Unit 1 8.7 4.8 - 12.6 - 3

Verulam Unit 2 8.2 2.5 - 16.2 1.36 33

Note: 1) Standard deviations are not presented for formations where the sample count was insufficient to

generate a meaningful result.

Direct Shear Testing

Direct shear testing (ASTM D 5607) was completed on limestone samples from within the Lindsay and Verulam

formations to determine the shear strength of joints within the tunnel alignment and shale samples from within

the Billings formation at the Downtown East station. Samples were collected of natural joint surfaces of


April 2011 Report No. 10-1121-0222 41

limestone, limestone with joints on shale bedding, and on saw cut surfaces to determine the lower bound

residual strength. Table 7-15 lists the results of the direct shear testing.

Table 7-15: Summary of Direct Shear Testing

Borehole ID

Sample Depth

(m)

Sample Elevation

(m) Formation Comments

Joint Description

Friction(o)

Cohesion (kPa)

T-46 8.85 65.40 Lindsay Unit 3 Shale along

bedding

Rough,

wavy 26 0

T-46 17.64 59.64 Lindsay Unit 3 Limestone Smooth,

wavy 26.6 0

T-39 26.07 38.98 Verulam Unit 2 Limestone Planar,

smooth 24 221

T-44 45.78 30.33 Verulam Unit 2 Limestone Rough,

wavy 20.3 112

T-43 51.97 27.95 Verulam Unit 2 Limestone Rough,

wavy 22.5 181

T-51 90.99 11.64 Verulam Unit 2 Saw Cut N/A 19.2 221

T-41 28.5 37.75 Verulam Unit 2 Limestone along

Shale bedding

Planar,

smooth 16 577


Shale bedding

Planar,

smooth 31.7 0


Shale bedding

Planar,

smooth 34.9 358

T-41 36.35 29.90 Verulam Unit 2 Limestone Wavy,

smooth 26.3 691

Triaxial Testing

Triaxial testing (ASTM D 2664) was completed on six rock core samples with confining pressure (σ3) of between

1.0 MPa and 10 MPa from within the tunnel horizon at each station. Table 7-16 lists the results of the triaxial

testing.

Table 7-16: Summary of Triaxial Testing

Borehole No.

Sample Depth (m)

Sample Elevation (m)

Formation Sigma 3

(MPa) Sigma 1

(MPa)

T-4 36.45 39.12 Verulam Unit 2 1 132.5

T-8 29.75 44.22 Lindsay Unit 1 3 107.5

T-46 42.97 43.02 Lindsay Unit 1 1 104.2

T-47 36.00 36.49 Verulam Unit 2 3 81.5

T-48 38.38 35.18 Verulam Unit 2 5 65.4


April 2011 Report No. 10-1121-0222 42

Borehole No.

Sample Depth (m)

Sample Elevation (m)

Formation Sigma 3

(MPa) Sigma 1

(MPa)

T-52 45.14 40.97 Lindsay Unit 1 10 159

Drillability and Abrasion Testing

A suite of abrasion and drillability testing on Lindsay and Verulam rock samples from within the tunnel horizon

were performed to provide a measure of the brittleness, rock abrasivity and strength for determining cutter wear

rate and costs. Tests include the following: Cerchar abrasion, Taber abrasion, Shore abrasion, Punch

penetration, Moh’s hardness and drillability testing. Drillability testing includes Brittleness Value (S20), Sievers'

J-Value (SJ), Abrasion Value (AV) and Abrasion Value Cutter Steel (AVS).

Tables 7-17 and 7-18 summarize the results of the abrasion and drillability testing results of the Lindsay and

Verulam formations. High abrasion values indicate higher rates of wear on mechanical tools. Both the limestone

and the shale units had very low abrasivity as would be expected for these rock types. The full suite of abrasion

tests was not completed on the shale as the tunnels are not expected to encounter shale based on the current

tunnel alignment.

Table 7-17: Summary of Lindsay Formation Abrasion and Drillability Results

Test Average Range Std. Dev. No.

Samples

Cerchar Abrasion 1.0 0.8 – 1.2 0.16 6

Taber Abrasion 12.7 12.7 – 12.7 0 1

Shore Abrasion 53.0 53.0 – 53.0 0 3

Punch Penetration (kips/in) 133.5 120.0 – 153.0 14.2 4

Moh’s Hardness 2.5 2.5 – 2.5 0 15

Drilling Rate Index 60 (High) n/a n/a 1

Bit Wear Index 40 (Very Low) n/a n/a 1

Cutter Life Index 107 (Extremely High) n/a n/a 1

Sievers’ J Value 102.6 90.3 – 111.6 9.32 1

Abrasion Value 1.0 1 – 1 0 1

Abrasion Value Cutter Steel 0.5 0 – 1 0.71 1

Table 7-18: Summary of Verulam Formation Abrasion and Drillability Results


Samples

Cerchar Abrasion 0.9 0.7 – 1.1 0.14 6

Taber Abrasion 18 10.2 – 23.0 5.3 5

Shore Abrasion 53.8 46.0 – 57.0 4.7 3

Punch Penetration 124.0 69.0 – 165.0 36.2 5

Moh’s Hardness 2.5 2.5 – 2.5 n/a 43

Drilling Rate Index 59 (High) n/a n/a 1

Bit Wear Index 12 (Very Low) n/a n/a 1


April 2011 Report No. 10-1121-0222 43


Samples

Cutter Life Index 101 (Extremely High) n/a n/a 1

Sievers’ J Value 86.9 68.2 – 116.3 18.0 1

Abrasion Value 0.5 0 – 1 0.71 1

Abrasion Value Cutter Steel 0.5 0 – 1 0.71 1

Petrographic Thin Section

A representative sample from the Lindsay and Verulam formations was selected for polished thin section and

petrographic description. Details of the petrographic analyses and thin section images are included in Appendix

E and are summarized below in Table 7-19.

Table 7-19: Summary of Petrographic Analyses

Formation Borehole

No. Depth (m) Description

Verulam Unit 2 T-47 36.7

Pure limestone containing fossil fragments Calcite 99.5% Pyrite trace, Bituminous matter trace Quartz trace

Lindsay Unit 3 T-51 20.4

Partially bituminous, bioclastic limestone Calcite 90% Bituminous material 9% Pyrite/marcasite 1%

Whole Rock Analysis

Six representative samples were selected for whole-rock analyses to characterize the mineral composition of the

rock mass along the tunnel alignment. Whole rock analyses is an X-Ray fluorescence spectroscopy to

determine a sample’s mineral composition of SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, Cr2O3, MnO, TiO2,

P2O5, V2O5 and LOI. The samples are listed below in Table 7-20 and details of the whole rock analyses are

presented in Appendix E and. In general, the samples comprise 40-50% CaO, 30-40% LOl, 7-15% SiO2 and

trace amounts of other components.

Table 7-20: Summary of Whole Rock Analyses

Formation Borehole

No. Depth (m)






Lindsay Unit 1 T-16 17.13


April 2011 Report No. 10-1121-0222 44

7.2.2 Rock Mass Quality

For the following bedrock descriptions, the proposed tunnel area was divided into six sections: West Portal,

Downtown West Station, Downtown East Station, Rideau Station, Rideau Station to East Portal, and East Portal.

Rock mass descriptions for each section include boreholes within the station and to the midpoint between the

adjacent stations. The rock mass quality values (Rock Quality Designation (RQD), Fracture Frequency, etc.) in

the different tunnel sections described below represent average values of all rock formations encountered in the

sections. Refer to Section 3.2.3.2 for definitions of the rock mass quality terms.

West Portal

In the West Portal tunnel area (boreholes W-056 to W-062, T-1 and T-2), the rock belongs to the Verulam

formation and consists of fresh to slightly weathered, thinly to medium bedded, grey to dark grey or black, fine to

medium grained, faintly to moderately porous, strong to medium strong limestone, interbedded with shale

seams. Locally the rock is fossiliferous, and fractured zones or calcite veins were intersected. The Verulam

formation interbeds are undulating to planar and consist of dark grey to black, calcareous shale up to 15 cm

thick.

The Rock Quality Designation (RQD) index, based on the borehole data for this tunnel section, ranges from 0%

to 100% with an average value of 85% (very poor to excellent and on average good quality rock). The average

rock strength index is R4 (strong rock) with an average weathering index of W1 (fresh rock). The fracture

frequency (fractures per metre) ranges from 0 to 125 fractures per m with an average of 7 fractures per m.

Excluding sections of broken core in the upper end of the core leads to an average fracture frequency of 3.4

fractures per m.

Downtown West Station

In the Downtown West Station tunnel area (boreholes T-3 to T-5, T-47 and T-48), the rock in the upper Lindsay

formation consists of fresh to slightly weathered, thinly to medium bedded, grey, fine to medium grained, strong

to medium strong limestone, interbedded with irregular black shale seams. Locally the rock is fossiliferous with

calcite veining. The rock in the underlying Verulam formation, within which the station will be excavated,

consists of fresh to slightly weathered, thinly to medium bedded, light to dark grey or brown, fine to medium

grained, faintly porous, strong to medium strong limestone, interbedded with occasional shale seams. The shale

interbeds are dark grey, calcareous shale up to 15 cm thick. Locally fractured zones or healed fractures were

found. The RQD index along the full borehole length drilled within the Downtown West Station section ranges

from 0% to 100% with an average RQD of 89% (very poor to excellent and on average good quality rock).

The rock strength index varies between R3 and R5 with an average of R4 (strong rock). The average

weathering index of W1.4 (range between W1 and W3) refers to fresh to slightly weathered rock. The fracture

frequency ranges from 0 to 99 with an average of 4 fractures per m.

Downtown East Station

In the Downtown East Station tunnel area (boreholes T-6 to T-9, T-44, T-46, T-51 and T-52), the near surface

rock mass consists of shale and limestone belonging to the Billings formation. The shale is fresh to slightly

weathered, thinly laminated to laminated, dark brown to dark grey or black, and weak to medium strong with

occasional grey limestone seams. The transitional contact between the Billings and Lindsay formation present in

these boreholes is typically several meters thick consisting of fresh to slightly weathered, thinly bedded to

massive, fine grained, black or brown to dark grey, medium strong to strong, fossiliferous shaly limestone with

shale seams and calcareous bedding seams. The shale content ranges from 40% to 50% within the transition


April 2011 Report No. 10-1121-0222 45

zone, Lindsay Unit 3. Beneath the Lindsay Unit 3, the limestone in the Lindsay Unit 2 and Lindsay Unit 1 (which

occurs within the station crown) is fresh, thinly bedded to massive, fine to medium grained, light grey to dark

brown, medium strong to very strong, fossiliferous, and interbedded with thin, undulated shale seams and locally

with fractured zones. Occasionally calcareous fragments were encountered in the core. The rock in the

Verulam formation, within which the station will be excavated, consists of fresh, very thinly to medium bedded,

light grey to grey, fine to coarse grained, very strong to medium strong limestone, interbedded with shale seams

and occasionally with sub-vertical carbonate veining. Locally fractured zones, healed fractures or calcite/quartz

veins were noted.

The RQD in this section varies between 13% and 100% with an average value of 93% (very poor to excellent

and on average excellent rock quality). The rock strength ranges from R2 to R5 with an average index of R4

(strong rock). The weathering index has a range from W1 to W2 and on average of W1 (fresh rock).

The fracture frequency ranges between 0 and 77 fractures per m and on average 3 fractures per m.

Rideau Station

In the Rideau Station tunnel area (boreholes T-10, T-11 and T-41 to T-43) the rock belongs to the Lindsay

formation and is described as fresh, thinly to medium bedded, light to dark grey, fine to medium grained,

moderately porous, strong to medium strong limestone interbedded with occasional thin, wavy shale seams.

Locally the limestone is fossiliferous, and occasionally fractures or healed fractures were noted. Beneath the

Lindsay formation, the rock in the Verulam formation (within which the station will be excavated) consists of

fresh, thinly to thickly bedded, light to dark grey, fine to medium grained, faintly porous, medium to strong

limestone, interbedded with thin, undulated, irregular shale seams. Locally fractured zones or healed fractures

up to 45 cm thick were found.

The RQD in the Rideau Station section varies between 0% and 100% with an average value of 84%, indicating

very poor to excellent and on average good rock quality. The rock strength ranges from R2 to R4 with an

average index of R3.5 (moderately to strong rock). The weathering index is W1 (fresh rock). The fracture

frequency ranges between 0 and 88 fractures per m with an average of 7 fractures per m.

Between Rideau Station and East Portal

In the tunnel section between Rideau Station and the East Portal (boreholes T-13 to T-16 and T-39) the rock in

the upper Lindsay formation consists of fresh, thinly bedded to massive, grey, fine grained, very strong to

medium strong, partly crystalline limestone interbedded with planar to undulating, weak shale seams.

Occasionally, the limestone has fractured zones, or healed or open fractures. Locally, carbonate veins were

found. The underlying Verulam formation consists of fresh to slightly weathered, locally highly weathered (lower

end of borehole T-13), thinly to medium or thickly bedded, grey, fine to coarse grained, very strong to medium

strong, locally weak limestone interbedded with planar to undulating shale seams and occasionally with highly

weathered clay seams. Occasionally, healed or open fractures, partly subvertical, fractured zones, or

quartz/calcite veins were found. Locally, conglomerate of grey and white rounded to angular clasts in grey matrix

was found.

The RQD index in this section ranges from 0% to 100% with an average RQD of 85% (very poor to excellent and

on average good quality rock). The rock strength index varies between R1 and R5 with an average of R4

(strong rock). The average weathering index of W1.1 refers to fresh rock with a range between W1 and W5. The

fracture frequency ranges from 0 to 83 with an average of 8 fractures per m.


April 2011 Report No. 10-1121-0222 46

The rock mass around the Rideau bedrock valley (between boreholes T-11 and T-13) is poor, highly fractured

(lower RQD) and significantly weathered. There is not enough information at this time to quantify the extent of

fractured rock around the Rideau Valley. Further drilling is planned during the last phase of drilling to delineate

the extent of the weathered rock mass.

East Portal

The East Portal area comprises boreholes T-35A and T-36. In this area, the surface bedrock changes from

limestone (Lindsay formation, T-32, T-35A and T-36) to shale (Billings formation, possible transition zone to

Lindsay, T-33A) directly south of the East Portal. The limestone belonging to the Lindsay formation is fresh to

slightly weathered, locally highly weathered, thinly to medium bedded, locally thickly to massive, light to dark

grey, fine to medium grained, medium strong to weak rock, interbedded with shale seams. Occasionally, vertical

to subvertical fractures or healed fractures were found.

The RQD in the East portal section varies between 0 and 100 with an average value of 80 (very poor to excellent

and on average good rock quality). The rock strength ranges from R0.5 to R3.5 with an average index of R3

(moderately strong rock). The weathering index has a range between W1.5 and W2 and on average of W2

(slightly weathered rock). The fracture frequency ranges between 0 and 34 fractures per m and on average 4

fractures per m.

7.3 Groundwater and Hydraulic Conductivity Monitoring wells were installed in the boreholes advanced for the concurrent geotechnical/environmental

investigation carried out for this project. The measured water levels in the monitoring wells are summarized

below:

Table 7-21: Summary of Measured Static Water Levels

Borehole No.

Date Water Level

Depth (mbgs) Water Level

Elevation (m) Screen Depth

(m) (1)

Strata of Screened Interval

T-AB February 17, 2011 4.2 69.3 4.9 – 7.9 Limestone

T-AC Monitoring Well Destroyed

T-AD February 17, 2011 6.6 65.4 6.7 – 9.8 Shale

T-AE February 17, 2011 5.6 66.1 2.6 – 5.6 Silty Sand

(Glacial Till)

T-AF February 17, 2011 Dry @ 5.7 m bgs 4.15 – 5.74 4.2 – 5.7

T-AG February 17, 2011 6.7 64.8 6.1 – 9.1 Shale

T-AH February 17, 2011 Dry @ 5.83 m bgs 4.75 – 6.27 4.8 – 6.3

T-AJ February 17, 2011 Dry @ 4.36 m bgs 2.90 – 4.42 2.9 – 4.4

T-AK February 17, 2011 3.8 60.4 3.1 – 6.1 Silty Clay

W-058 January 20, 2011 3.7 57.7 3.8 – 6.9 Sandy Silt

(Glacial Till)

W-060 January 20, 2011 3.5 57.7 2.1 – 5.6 Silty Sand

(Glacial Till)

W-062 January 20, 2011 2.6 60.3 2.7 – 5.8 Silty Sand

(Glacial Till)

T-5 January 20, 2011 2.5 69.5 36.0 – 43.6 Limestone


April 2011 Report No. 10-1121-0222 47

Borehole No.

Date Water Level

Depth (mbgs) Water Level

Elevation (m) Screen Depth

(m) (1)

Strata of Screened Interval


T-12 January 20, 2011 6.4 57.6 21.8 – 29.41 Silty Sand

(Glacial Till)


T-35A January 20, 2011 9.7 61.7 13.5 - 21.1 Limestone

Note: (1) Monitoring well installation details are located on the borehole logs in Appendix A and B. Screen depths are for the

depth of the slotted PVC screen plus sand pack.

Water level dataloggers were installed in some of the monitoring wells to record the static water level on a daily

basis and the results of that monitoring are shown on Figure 7.3.

The static water level at borehole T-5 appeared to vary in response to rainfall and it is considered that this is

inconsistent, considering the well depth and the quality of rock encountered in this borehole. This may have

been due to a faulty seal at the flush mount or well cap.

Groundwater levels are expected to fluctuate seasonally and higher groundwater levels are expected during wet

periods of the year (such as spring), particularly for the shallow water levels in the overburden. The water levels

within the bedrock at depth will likely not exhibit the same degree of fluctuation.

Monitoring wells were installed in the overburden boreholes T-12, W-058, W-060 and W-062 and in the rock in

boreholes T-5, T-10. T-13, and T-35. Rising head permeability tests were carried out in the monitoring wells

installed within the overburden materials and across the bedrock. Static groundwater levels were established

prior to testing. The rate of water level recovery in the monitoring well was measured following the rapid removal

of a known quantity of water. A summary of the hydraulic conductivity testing carried out in the overburden and

bedrock is presented in Table 7-22.

Table 7-22: Summary of Field Hydraulic Conductivity Test Results

Borehole No.

Strata of Test Interval Test Interval

(m bgs)

Hydraulic Conductivity

(cm/s)

T-5 Limestone Bedrock 36.0 – 43.6 3 x 10-4


T-12 Glacial Till (with Sand layer) 21.8 – 29.4 2 x 10-4



W-058 Glacial Till 3.1 – 7.6 2 x 10-6

W-060 Glacial Till 2.1 – 5.6 5 x 10-6

W-062 Glacial Till 2.4 – 6.1 1 x 10-6


April 2011 Report No. 10-1121-0222 48

Falling head and/or constant head packer tests were carried out within the rock approximately every ten meters. The results of the packer testing are indicated on the Record of Drillhole sheets and are summarized in Table 7-23 and Appendix H. Note if a falling head and constant head packer test was completed within the same depth interval, the falling head hydraulic conductivity value is shown in the Record of Drillhole sheet as falling head tests were conducted more frequently than constant head tests.

Table 7-23: Summary of Hydraulic Conductivity Packer Test Results in Rock

Borehole No.

Inclination (degrees) Interval

Vertical Depth of Test Interval

(m below ground surface) Rock Unit

Hydraulic Conductivity (cm/s)

From To Falling Head Constant Head

T-1 68

1 8.34 14.19 Verulam Unit 2 2 x 10-4

2 12.61 19.75 Verulam Unit 2 2 x 10-5

3 18.64 29.61 Verulam Unit 2 3 x 10-6

T-3 72 1 23.02 33.29 Verulam Unit 2 2 x 10-7

T-5 68

1 24.71 32.61 Lindsay Unit 1 / Verulam Unit

2 1 x 10-7

2 34.39 42.66 Verulam Unit 2 7 x 10-7

3 43.51 51.08 Verulam Unit 2 2 x 10-6

T-6 68 1 18.27 49.01 Lindsay Unit 1 / Verulam Unit

2 3 x 10-5

T-7 67

1 8.56 20.80 Lindsay Unit 3 / Unit 2 1 x 10-4 4 x 10-4

2 20.80 36.23 Lindsay Unit 2 / Unit 1 2 x 10-6

3 34.61 48.54 Verulam Unit 2 9 x 10-7

T-8 73

1 10.81 27.64 Lindsay Unit 3 /Unit 2 7 x 10-6

2 27.06 41.98 Lindsay Unit 1 5 x 10-6

3 39.30 51.16 Verulam Unit 2 7 x 10-6

T-9 70

1 8.18 17.01 Billings /Lindsay Unit 3

5 x 10-6

2 16.82 34.11 Lindsay Unit 3 / Unit 2 3 x 10-7

3 32.80 54.13 Lindsay Unit 2/

Unit 1/ Verulam Unit 2

2 x 10-6


April 2011 Report No. 10-1121-0222 49

Borehole No.






T-10 69

1 3.83 13.82 Lindsay Unit 1 7 x 10-5 No take

2 12.42 28.01 Verulam Unit 2 1 x 10-5

3 26.42 42.30 Verulam Unit 2 6 x 10-6

T-11 70

1 15.32 25.28 Verulam Unit 2 3 x 10-4 5 x 10-4

2 23.68 33.83 Verulam Unit 2 5 x 10-5

3 32.23 42.27 Verulam Unit 2 2 x 10-5

T-13 89 1 8.70 21.00 Lindsay Unit 1 7 x 10-5

2 19.30 40.49 Verulam Unit 2 6 x 10-5

T-14 69 1 5.88 18.39 Lindsay Unit 1 4 x 10-5 2 x 10-5

2 17.36 36.87 Verulam Unit 2 6 x 10-5 3 x 10-5

T-15 69 1 7.56 21.19 Lindsay Unit 1 3 x 10-6

2 18.95 35.49 Verulam Unit 2 5 x 10-6

T-16 71

1 7.19 17.40 Lindsay Unit 1 9 x 10-4

2 15.79 33.12 Lindsay Unit 1 /Verulam Unit

2 9 x 10-5 2 x 10-4

T-35 90

1 10.36 16.43 Lindsay Unit 2 2 x 10-5 3 x 10-4

2 16.10 23.91 Lindsay Unit 1 5 x 10-5 4 x 10-4

3 24.45 32.00 Verulam Unit 2 1 x 10-5

T-36 90

1 11.43 16.52 Lindsay Unit 2 / Lindsay Unit

1 8 x 10-4 2 x 10-4

2 16.35 22.66 Lindsay Unit 1 2 x 10-6


2 2 x 10-6

T-39 69

1 13.40 21.85 Verulam Unit 2 8 x 10-6 4 x 10-5

3 21.11 32.12 Verulam Unit 2 2 x 10-7

4 30.92 39.16 Verulam Unit 2 3 x 10-6


April 2011 Report No. 10-1121-0222 50

Borehole No.






T-41 90

1 16.14 25.50 Verulam Unit 2 2 x 10-4

2 25.16 34.48 Verulam Unit 2 9 x 10-7

3 34.69 45.11 Verulam Unit 2 4 x 10-5 4 x 10-5

T-42 74

1 17.31 23.10 Verulam Unit 2 2 x 10-6

2 23.04 32.94 Verulam Unit 2 2 x 10-7

3 32.88 44.38 Verulam Unit 2 8 x 10-6 2 x 10-6

T-43 72


2 5 x 10-7

2 14.39 24.66 Verulam Unit 2 1 x 10-7

3 24.39 34.78 Verulam Unit 2 2 x 10-7

4 33.78 54.35 Verulam Unit 2 1 x 10-6

T-44 67

1 23.62 33.53 Lindsay Unit 2 / Lindsay Unit

1 4 x 10-6

2 33.36 41.84 Lindsay Unit 1 2 x 10-6

3 41.70 51.58 Verulam Unit 2 4 x 10-7

T-46 41

1 23.62 31.61 Lindsay Unit 2 7 x 10-6

2 31.60 39.51 Lindsay Unit 2 /Lindsay Unit 1 3 x 10-7

3 39.09 47.47 Lindsay Unit 1 8 x 10-8


2 1 x 10-7

T-47 90

1 7.49 16.75 Lindsay Unit 1 2 x 10-4 2 x 10-6

2 16.55 25.86 Lindsay Unit 1 7 x 10-8

3 25.73 36.42 Verulam Unit 2 7 x 10-5 7 x 10-5

4 36.47 50.15 Verulam Unit 2 4 x 10-9


April 2011 Report No. 10-1121-0222 51

Borehole No.

Inclination (degrees)

Interval




From To Falling Head Constant

Head

T-51 41

1 14.62 18.61 Lindsay Unit 3 7 x 10-6 1 x 10-5

2 10.69 12.51 Lindsay Unit 3 8 x 10-5

3 22.56 31.50 Lindsay Unit 3 2 x 10-7

4 28.53 37.43 Lindsay Unit 3

/ Unit 2 2 x 10-5

5 36.45 45.42 Lindsay Unit 2 1 x 10-5

6 45.37 49.39 Lindsay Unit 1 2 x 10-5

7 48.37 55.37 Lindsay Unit 1 2 x 10-7

T-52 42

1 24.43 31.38 Lindsay Unit 2 9 x 10-6

2 30.47 39.52 Lindsay Unit 2

/ Unit 1 3 x 10-6

3 47.68 39.45 Lindsay Unit 1 1 x 10-5

4 47.66 55.75 Lindsay Unit 1 /Verulam Unit

2 7 x 10-4 2 x 10-4

A 51.91 55.75 Verulam Unit 2 4 x 10-4

B 49.17 52.19 Lindsay Unit 1 1 x 10-6

C 45.82 48.85 Lindsay Unit 1 3 x 10-4 3 x 10-5

Notes: (*1) Very slow response, only 1% recovery at end of test. (*2) Only one pressure.

7.4 In Situ Stress Measurements A hydraulic fracturing (hydro-fracturing) stress measurement program was carried out in Boreholes T-41, T-44

and T-48 between November 15th and 19th 2010. The boreholes used in this testing were drilled 96mm (HQ3)

diameter. The measurements followed the ASTM test procedure for hydraulic fracturing stress measurements,

ASTM D 4645-87 (Standard Test Method for Determination of the In-Situ Stress in Rock Using the Hydraulic

Fracturing Method). The testing consisted of two parts, fracture generation and fracture orientation

determination. The orientation of boreholes T-41 and T-48 were vertical while borehole T-44 had a plunge of

approximately 68˚ and a trend of approximately 52˚. The testing depths are presented in Table 7-24 and were

selected as close to the respective station horizons, at the borehole locations, as was possible considering that

zones of relatively few existing discontinuities were required for proper testing.


April 2011 Report No. 10-1121-0222 52

Table 7-24: Hydrofracture Testing Zones and Lithology

Borehole No.

Test No.

Depth (m along hole) Vertical Depth to

Centre of Test Zone (m)

Lithology

From To

T-41 (Vertical) Rideau Station

1 27.6 28.6 28.1 Limestone

2 29.8 30.8 30.3 Limestone

3 34.3 35.3 34.8 Limestone

4 41.2 42.2 41.7 Limestone

T-44 (Inclined) Downtown East Station

1 34.0 35.0 32.0 Limestone

2 37.0 38.0 34.8 Limestone

3 41.7 42.7 39.1 Limestone

T-48 (Vertical) Downtown West Station

1 25.2 26.2 25.7 Limestone

2 35.3 36.3 35.8 Limestone

3 38.8 39.8 39.3 Limestone

Only one of the ten tests conducted, exhibited a vertical fracture that can be considered a classic hydraulic

fracture. Consequently the horizontal stresses could only be calculated at an along hole depth of approximately

34.5 m in Borehole T-44. The minimum horizontal stress, based on the Cycle 1 breakdown pressure (employing

the laboratory scale tensile strength), and the Cycle 2 reopening pressure, were calculated to be 1.7 MPa and

2.1 MPa respectively, while the maximum horizontal stress was calculated to range from 5.1 to 11.2 MPa for the

cycle 2 reopening pressure and cycle 1 breakdown pressure respectively. The maximum horizontal stress

direction for this test had an azimuth of approximately 103˚.

Table 7-24 below presents the calculated stress values for test number 1 from borehole T-44. The table also

includes the calculated vertical stress, v values based on an average rock density of 2690 kg/m3. The

minimum stress interpretations use the second cycle derivative value (Pdpdt). The rationale for using the second

cycle is that the fracture should be sufficiently developed to give a good shut in pressure, but not so extended

that it may rotate from the plane normal to Hmin or extend into the rockmass with stresses different from those

immediately around the borehole.

The maximum horizontal stress value based on the first cycle breakdown pressure is higher than the value

based on the second cycle re-opening pressure. This difference depends on the value of tensile strength used

in the first cycle stress calculation.


April 2011 Report No. 10-1121-0222 53

The hydrofracturing testing procedures and theoretical background are presented in detail in Appendix F.

Table 7-25: Summary of Calculated Stress Values in the Global Co-ordinate System

Borehole No.

Test No.

Vertical Depth

σHMax σHMin

σv T Ph

Water Column

Po Pore

Pressure

Fracture OrientationCycle

1 Cycle

2 Cycle

1 Cycle

2

(m) (MPa) (MPa) (MPa) (MPa) (MPa) (MPa) (MPa) (MPa)Dip

Direction (˚)

T-44 1 32.0 11.2 5.1 1.7 2.1 0.84 8.7 0.31 0.15 193


April 2011 Report No. 10-1121-0222 54

8.0 CLOSURE The data in this Interim Geotechnical Data Report will be updated throughout the project as the detailed drilling investigation is carried out.

GOLDER ASSOCIATES LTD.

Megan Roworth, P.Eng. William (Bill) Cavers, P.Eng. Rock Engineer Geotechnical Engineer Mark J. Telesnicki Principal MR/JC/WC/MJT/ca/am n:\active\2010\1121 - geotechnical\10-1121-0222 ctp olrt ottawa\reports\final stage 1 & 2 tunnel gdr report\text\orp_gal_mjt_interim stage 1 and 2 geotechnical data report tunnel_20110429.docx


April 2011 Report No. 10-1121-0222 55

REFERENCES Barton, N.R., Lien, R. and Lunde, J. 1974. Engineering classification of rock masses for the design of tunnel

report. Rock Mech. 6(4), 189-239.

Bieniawski, Z.T. 1976. Rock mass classification in rock engineering. In Exploration for rock engineering, proc. of

the symp., (ed. Z.T. Bieniawski) 1, 97-106. Cape Town: Balkema.

Belanger, J.R. “Urban Geology of Canada’s National Capital Area”, in Urban Geology of Canadian Cities,

Geological Association of Canada Special Paper 42, Ed. P.F. Karrow and O.L. White, 1998.

Chapman, L.J. and D.F. Putnam. The Physiography of Southern Ontario, Ontario Geological Survey Special

Volume 2, Third Edition, 1984. Accompanied by Map P.2715, Scale 1:600,000.

CFEM. 2006. Canadian Foundation and Engineering Manual. 4th Edition. Canadian Geotechnical Society.

BiTech Publishing.

City of Ottawa. 2009. “Downtown Ottawa Transit Tunnel: Tunney’s Pasture to Blair Station via a Downtown LRT

Tunnel.” Issued December 2009.

Deere and Deere. 1988. "The RQD index in practice", Proc. Symp. Rock Class. Engineering Purposes, ASTM

Special Technical Publications 984, Philadelphia, (91-101).

Golder, 2002. Results from Phase 2 Field Investigation, Somerset Wastewater Storage Facility Project, Ottawa,

Ontario. Report 991-2211. Issued June 2002.

Hvorslev, M.J. (1951). Time Lag and Soil Permeability in Groundwater Observations: U.S. Army Corps of Eng.

Waterway Exp. Stat. Bull. 36 (Vicksburg, Miss).

ISRM 1981. Rock characterization, testing and monitoring. International Society for Rock Mechanics, Suggested

Methods, Pergamon Press, Oxford. Brown, E.T. (ed.).

Williams, D.A., 1991. Paleozoic Geology of the Ottawa-St. Lawrence Lowland, Southern Ontario; Ontario

Geological Survey, Open File Report 5770, 292p.

Wilson, AE, 1946. Geology of the Ottawa-St. Lawrence Lowland, Ontario and Quebec. Geological Survey of

Canada, Memoir 241.

Williams, D.A. et al. 1984. Paleozoic Geology of the Ottawa-Area Southern Ontario; Ontario Geological Survey,

Map P. 2716, Geological Series - Preliminary Map, Scale 1:50 000.

Golder Associates Ltd. Page 1 of 2

IMPORTANT INFORMATION AND LIMITATIONS OF THIS REPORT

Standard of Care: Golder Associates Ltd. (Golder) has prepared this report in a manner consistent with that level of care and skill ordinarily exercised by members of the engineering and science professions currently practising under similar conditions in the jurisdiction in which the services are provided, subject to the time limits and physical constraints applicable to this report. No other warranty, expressed or implied is made.

Basis and Use of the Report: This report has been prepared for the specific site, design objective, development and purpose described to Golder by the Client, . The factual data, interpretations and recommendations pertain to a specific project as described in this report and are not applicable to any other project or site location. Any change of site conditions, purpose, development plans or if the project is not initiated within eighteen months of the date of the report may alter the validity of the report. Golder can not be responsible for use of this report, or portions thereof, unless Golder is requested to review and, if necessary, revise the report.

The information, recommendations and opinions expressed in this report are for the sole benefit of the Client. No other party may use or rely on this report or any portion thereof without Golder's express written consent. If the report was prepared to be included for a specific permit application process, then the client may authorize the use of this report for such purpose by the regulatory agency as an Approved User for the specific and identified purpose of the applicable permit review process, provided this report is not noted to be a draft or preliminary report, and is specifically relevant to the project for which the application is being made. Any other use of this report by others is prohibited and is without responsibility to Golder. The report, all plans, data, drawings and other documents as well as all electronic media prepared by Golder are considered its professional work product and shall remain the copyright property of Golder, who authorizes only the Client and Approved Users to make copies of the report, but only in such quantities as are reasonably necessary for the use of the report by those parties. The Client and Approved Users may not give, lend, sell, or otherwise make available the report or any portion thereof to any other party without the express written permission of Golder. The Client acknowledges that electronic media is susceptible to unauthorized modification, deterioration and incompatibility and therefore the Client can not rely upon the electronic media versions of Golder's report or other work products.

The report is of a summary nature and is not intended to stand alone without reference to the instructions given to Golder by the Client, communications between Golder and the Client, and to any other reports prepared by Golder for the Client relative to the specific site described in the report. In order to properly understand the suggestions, recommendations and opinions expressed in this report, reference must be made to the whole of the report. Golder can not be responsible for use of portions of the report without reference to the entire report.

Unless otherwise stated, the suggestions, recommendations and opinions given in this report are intended only for the guidance of the Client in the design of the specific project. The extent and detail of investigations, including the number of test holes, necessary to determine all of the relevant conditions which may affect construction costs would normally be greater than has been carried out for design purposes. Contractors bidding on, or undertaking the work, should rely on their own investigations, as well as their own interpretations of the factual data presented in the report, as to how subsurface conditions may affect their work, including but not limited to proposed construction techniques, schedule, safety and equipment capabilities.

Soil, Rock and Groundwater Conditions: Classification and identification of soils, rocks, and geologic units have been based on commonly accepted methods employed in the practice of geotechnical engineering and related disciplines. Classification and identification of the type and condition of these materials or units involves judgment, and boundaries between different soil, rock or geologic types or units may be transitional rather than abrupt. Accordingly, Golder does not warrant or guarantee the exactness of the descriptions.

Capital Transit Partners

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IMPORTANT INFORMATION AND LIMITATIONS OF THIS REPORT (cont'd)

Special risks occur whenever engineering or related disciplines are applied to identify subsurface conditions and even a comprehensive investigation, sampling and testing program may fail to detect all or certain subsurface conditions. The environmental, geologic, geotechnical, geochemical and hydrogeologic conditions that Golder interprets to exist between and beyond sampling points may differ from those that actually exist. In addition to soil variability, fill of variable physical and chemical composition can be present over portions of the site or on adjacent properties. The professional services retained for this project include only the geotechnical aspects of the subsurface conditions at the site, unless otherwise specifically stated and identified in the report. The presence or implication(s) of possible surface and/or subsurface contamination resulting from previous activities or uses of the site and/or resulting from the introduction onto the site of materials from off-site sources are outside the terms of reference for this project and have not been investigated or addressed.

Soil and groundwater conditions shown in the factual data and described in the report are the observed conditions at the time of their determination or measurement. Unless otherwise noted, those conditions form the basis of the recommendations in the report. Groundwater conditions may vary between and beyond reported locations and can be affected by annual, seasonal and meteorological conditions. The condition of the soil, rock and groundwater may be significantly altered by construction activities (traffic, excavation, groundwater level lowering, pile driving, blasting, etc.) on the site or on adjacent sites. Excavation may expose the soils to changes due to wetting, drying or frost. Unless otherwise indicated the soil must be protected from these changes during construction.

Sample Disposal: Golder will dispose of all uncontaminated soil and/or rock samples 90 days following issue of this report or, upon written request of the Client, will store uncontaminated samples and materials at the Client's expense. In the event that actual contaminated soils, fills or groundwater are encountered or are inferred to be present, all contaminated samples shall remain the property and responsibility of the Client for proper disposal.

Follow-Up and Construction Services: All details of the design were not known at the time of submission of Golder's report. Golder should be retained to review the final design, project plans and documents prior to construction, to confirm that they are consistent with the intent of Golder's report.

During construction, Golder should be retained to perform sufficient and timely observations of encountered conditions to confirm and document that the subsurface conditions do not materially differ from those interpreted conditions considered in the preparation of Golder's report and to confirm and document that construction activities do not adversely affect the suggestions, recommendations and opinions contained in Golder's report. Adequate field review, observation and testing during construction are necessary for Golder to be able to provide letters of assurance, in accordance with the requirements of many regulatory authorities. In cases where this recommendation is not followed, Golder's responsibility is limited to interpreting accurately the information encountered at the borehole locations, at the time of their initial determination or measurement during the preparation of the Report.

Changed Conditions and Drainage: Where conditions encountered at the site differ significantly from those anticipated in this report, either due to natural variability of subsurface conditions or construction activities, it is a condition of this report that Golder be notified of any changes and be provided with an opportunity to review or revise the recommendations within this report. Recognition of changed soil and rock conditions requires experience and it is recommended that Golder be employed to visit the site with sufficient frequency to detect if conditions have changed significantly.

Drainage of subsurface water is commonly required either for temporary or permanent installations for the project. Improper design or construction of drainage or dewatering can have serious consequences. Golder takes no responsibility for the effects of drainage unless specifically involved in the detailed design and construction monitoring of the system.

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