J.L. Richards & Associates Limited 864 Lady Ellen Place Ottawa, Ontario K1Z 5M2. April 6, 2015 Project:

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1 Houle Chevrier Engineering Ltd. 180 Wescar Lane Ottawa, Ontario K0A 1L0 tel: fax: J.L. Richards & Associates Limited 864 Lady Ellen Place Ottawa, Ontario K1Z 5M2 April 6, 15 Project: Attention: Ms. Katelyn Morphet, MCIP, RPP Re: Test Pit Investigation Proposed Office and Modular Service Shop 3150 Rideau Road Ottawa, Ontario This report presents the results of a test pit investigation carried out at the site of a proposed site office, modular service shop and associated parking for Williams Scotsman of Canada Inc. at 3150 Rideau Road in the City of Ottawa, Ontario. The purpose of the investigation was to identify the general subsurface conditions in the area of the proposed buildings and parking area by means of a limited number of test pits. Based on the subsurface conditions encountered in the test pits, geotechnical guidelines and recommendations are provided for the proposed development. BACKGROUND INFORMATION Plans are being prepared to place a portable site office and construct a modular service shop and associated parking at 3150 Rideau Road in Ottawa, Ontario (refer to Key Plan, Figure 1). There is an existing building (The Brickyards) west of the subject property and the area of the proposed development is currently covered with granular material. It is understood that the following is proposed for the site: A portable site trailer, which will act as the site office. A portable service shop, consisting of a modular building having dimensions of about 60 x 70 feet (18 x 21 metres). geotechnical environmental hydrogeology materials testing & inspection

2 An at grade, asphaltic concrete surfaced parking area. An at grade, gravel surfaced work yard. It is understood that the portable buildings will be supported on dry stacked concrete block piers resting on pre-cast concrete pads. It is understood that the pre-cast concrete pads are to be placed at ground surface and that the piers are designed for regular adjustment and can accommodate movement due to frost heaving and/or settlement of the soil below the pre-cast concrete pads. A proprietary ground anchor system (Arrowhead, Cat. No. Arrow-1) is included in the foundation design for the service shop, with ground anchors extending to 1.2 metres below ground surface at regular intervals throughout the building. SITE GEOLOGY Based on available geological information, it is expected that the site is underlain by bedrock at depths ranging from near surface to about 1 metre below ground surface. Bedrock geology maps indicate that the bedrock is composed of dolostone of the Oxford formation. Fill material associated with the current and past use of the site should also be expected. SUBSURFACE INVESTIGATION The field work for this investigation was carried out on March 12, 15. At that time, five (5) test pits, numbered to , inclusive, were advanced at the site using a large, track mounted, hydraulic excavator. The test pits were advanced to depths ranging from about 1.2 to 2.1 metres below ground surface. The subsurface conditions encountered in the test pits were identified by visual and tactile examination of the materials exposed on the sides and bottom of the test pits. Samples of the soils in the test pits were recovered manually. The groundwater conditions in the open test pits were observed during the short period of time that the test pits were left open. The test pits were then loosely backfilled with the excavated materials and tamped with the bucket of the excavator. As such, the test pits represent areas of soil disturbance. The field work was supervised throughout by a member of our engineering staff. The locations of the test pits and the ground surface elevations at the test pit locations were determined using our Trimble global positioning system and are provided on the Test Pit Location Plan, Figure 2. The elevations are referenced to geodetic datum. The results of the test pits are provided on the Record of Test Pit sheets in Attachment A. SUBSURFACE CONDITIONS General As previously indicated, the soil and groundwater conditions logged in the test pits are provided on the Record of Test Pit sheets in Attachment A. The logs indicate the subsurface conditions Report to: J.L. Richards & Associates Limited Project: (April 6, 15) 2

3 at the specific test locations only. Boundaries between zones on the logs are often not distinct, but rather are transitional and have been interpreted. The precision with which subsurface conditions are indicated depends on the frequency and recovery of samples, the method of sampling and the uniformity of the subsurface conditions. Subsurface conditions at other than the test locations may vary from the conditions encountered in the test pits. The groundwater conditions described in this report refer only to those observed at the test pit locations and time of observation noted in the report. The groundwater conditions may vary seasonally or as a consequence of other factors such as construction activity. The soil descriptions in this report are based on commonly accepted methods of classification and identification employed in geotechnical practice. Classification and identification of soil involves judgement and Houle Chevrier Engineering Ltd. does not guarantee descriptions as exact, but infers accuracy to the extent that is common in current geotechnical practice. The following presents an overview of the subsurface conditions encountered at the test pit locations. Granular Fill Material From ground surface all of the test pits encountered a layer of grey, crushed sand and gravel, with trace to some silt. The thickness of the sand and gravel ranges from about 0.4 to 0.9 metres at the test pit locations. Earth Fill Material Earth fill material composed of brown to dark brown silty fine sand with trace to some gravel was encountered below the granular fill material at all of the test pit locations. Miscellaneous debris (e.g. brick, asphaltic concrete and metal) were encountered within the silty sand fill material. The thickness of the earth fill ranges from about 0.4 to 1.6 metres, with an arithmetic average of about 1 metre. Probable Bedrock All of the test pits were terminated on probable bedrock at depths ranging from about 1.2 to 2.1 metres below ground surface (elevation to metres, geodetic datum). Groundwater Conditions No groundwater inflow was observed in the test pits during the relatively short period of time that they were left open following excavation. It should be noted that this does not represent stabilized groundwater conditions. Furthermore, the groundwater level could be higher during wet periods of the year such as the early spring. Report to: J.L. Richards & Associates Limited Project: (April 6, 15) 3

4 GEOTECHNICAL GUIDELINES AND RECOMMENDATIONS Excavation As indicated above, the foundation plans provided to us indicate that the foundations for the modular service shop will be founded at existing surface grade, which would not necessitate excavation at the site. If excavation is required for conventional, shallow depth foundations, the excavations would be taken through granular and earth fill material. The sides of any excavations should be sloped in accordance with the requirements in Ontario Regulation 213/91 under the Occupational Health and Safety Act. According to the Act, the fill can be classified as Type 3 soil and, accordingly, allowance should be made for excavation side slopes of 1 horizontal to 1 vertical extending upwards from the base of the excavation. Groundwater inflow into the excavations should be handled by pumping from within the excavations. Building Foundations General The results of the test pits indicate that the area of the proposed development is underlain by granular and earth fill material followed by bedrock. The total thickness of the earth fill material ranges from about 1.2 to 2.1 metres. It is understood that the foundations are designed to accommodate movement due to frost heaving and/or settlement of the soil below the pre-cast concrete pads. As such, settlement due to post construction densification of the fill material may be acceptable. It is pointed out that the magnitude of the forces on the ground anchors caused by frost action could exceed the capacity of the anchors. This may require the anchors to be re-set or adjusted seasonally. The structural plans provided to us specify a bearing value of 3,000 pounds per square foot (145 kilopascals) for the subgrade soil below the piers. Due to the fill material at this site, post construction settlement at the specified bearing value may exceed what would be expected for typical construction of permanent foundations (i.e. settlement may exceed 25 millimetres). However, since the pier foundations are designed for regular adjustment, the granular and earth fill material encountered in the test pits is considered suitable for the support of these building foundations. Due to potential for variability of the fill material, it is recommended that the building footprint be heavily proof rolled with a large diameter vibratory roller (minimum 10 tonne). Any soft areas observed during the proof roll should be subexcavated and replaced with granular material meeting Ontario Provincial Standard Specification (OPSS) requirements for Granular B Type II, compacted in maximum 0 millimetre thick lifts to at least 98 percent of the standard Proctor dry density value. Report to: J.L. Richards & Associates Limited Project: (April 6, 15) 4

5 Following the proof roll, field density testing should be carried out at regular intervals throughout the building footprint to ensure that the granular material has been compacted to at least 98 percent of the standard Proctor dry density value, in accordance with notes on the structural plans provided to us. Other alternatives to reduce the potential for post construction settlement (e.g. removal and replacement of existing fill material) could be provided, if required. Frost Protection of Foundations As indicated above, the structural plans provided to us indicate that the piers are designed for regular adjustment due to frost heave. As such, typical frost protection of foundations is not considered necessary. Seismic Site Classification The subsurface conditions in the vicinity of the buildings consist of about 1 to 2 metres of granular and earth fill material above probable bedrock. If the proposed structures are founded on the fill material overlying the bedrock Site Class D could be used for the seismic design of the structure. Based on the subsurface conditions encountered, it is our opinion that the potential for liquefaction is negligible. Parking Area and Work Yard Subgrade Preparation The existing granular material is considered suitable as a subbase for the parking area and the work yard. However, prior to placing granular base material, the parking area and work yard should be heavily proof rolled with a large (10 tonne) vibratory steel drum roller under dry conditions. Any soft areas evident from the proof rolling should be subexcavated and replaced with granular material meeting Ontario Provincial Standard Specification (OPSS) requirements for Granular B Type II. It is not considered necessary to remove the existing silty sand fill material as long as the surface is heavily proof rolled and provided that some localized settlement is tolerable. Pavement Structure Asphaltic Concrete Surfaced Parking Lot The following pavement structure is suggested for the parking area at this site: 75 millimetres of OPSS HL3 (or Superpave 12.5) asphaltic concrete, over 150 millimetres of OPSS Granular A base, over Existing granular material Report to: J.L. Richards & Associates Limited Project: (April 6, 15) 5

6 Performance grade PG58-34 asphaltic concrete should be specified. Gravel Surfaced Work Yard The following pavement structure is suggested for the work yard at this site: 150 millimetres of OPSS Granular A base, over Existing granular material Granular Material Placement The granular base material should be compacted in maximum 0 millimetre thick lifts (i.e. one lift, unless subexcavation and replacement of any soft areas is required) to at least 98 percent of the standard Proctor maximum dry density value. Transition Treatments In areas where the new pavement structure will abut existing pavement, the depths of the granular materials should taper up or down at 5 horizontal to 1 vertical, or flatter, to match the depths of the granular material(s) exposed in the existing pavement. Drainage Adequate drainage of the pavement granular materials and subgrade is important for the long term performance of the pavement at this site. As such it is suggested that suitable ditching or swales should be constructed around parking area and work yard. The granular subbase and base layers should extend to these ditches or swales. ADDITIONAL CONSIDERATIONS Disposal of Excess Soil It is noted that the professional services retained for this project include only the geotechnical aspects of the subsurface conditions at this site. The presence or implications of possible surface and/or subsurface contamination, including naturally occurring sources of contamination, are outside the terms of reference for this report. This report does not constitute a contaminated material management plan or an excess soil management plan. Disturbed Soil from Geotechnical Investigation The soil backfilled in the test pits advanced as part of the geotechnical investigation is considered to be disturbed soil. In areas where disturbed subsoil is encountered within the building footprint or hard surfaced areas (parking area, walkway, etc.), the disturbed material should be removed and replaced with suitable compacted granular material, such as that meeting OPSS Granular B Type I or II. Report to: J.L. Richards & Associates Limited Project: (April 6, 15) 6

7 Effects of Construction Induced Vibration Some of the construction operations (such as granular material compaction, etc.) will cause ground vibration on and off of the site. The vibrations will attenuate with distance from the source, but may be felt at nearby structures. The magnitude of the vibrations will be much less than that required to cause damage to the nearby structures or services in good condition. Design Review and Construction Observation The engagement of the services of the geotechnical consultant during construction is recommended to carry out proof roll inspections and field density testing on the existing and imported granular materials in the building footprint and parking lot areas to ensure that the materials used conform to the grading and compaction specifications. We trust that this report is sufficient for your purposes. Please contact the undersigned if you have any questions concerning this information. Brent Wiebe, P.Eng. Senior Engineer 06 Apr 15 Craig Houle, M.Eng., P.Eng. Figures 1 and 2 Attachment A Report to: J.L. Richards & Associates Limited Project: (April 6, 15) 7

8 NOT TO SCALE 32 Steacie Drive, Ottawa, ON T: (613) Project GEOTECHNICAL INVESTIGATION 3150 RIDEAU ROAD OTTAWA, ON Drwn By Chkd By Date Drawing Project No. KEY PLAN Revision No. PC BW APRIL 6, FIGURE 1

9 KEY PLAN NOT TO SCALE PROPOSED BUILDING BANK STREET BANK STREET RIDEAU ROAD GATE 1.2m WIDE ASPHALT WALKWAY FENCE TP 105 TYP. 2.6m x 5.2m X PARKING SPACES TP 103 ASPHALT PAKING PORTABLE OFFICE E W E 24'x60' PORTABLE SHOP 60'x72' E W 0.00m FENCE m 18.30m 15.24m EXISTING DRIVEWAY (GRANULAR) TP 104 TP m TP 102 LEGEND TP TEST PIT LOCATION IN PLAN (current investigation by Houle Chevrier Engineering) CURRENT GROUND SURFACE ELEVATION IN METRES GEODETIC DATUM Scale 1: m Houle Chevrier Engineering 32 Steacie Drive Ottawa, ON Tel: (613) ottawa@hceng.ca Client Project J.L. RICHARDS ASSOCIATES LTD Location 3150 RIDEAU ROAD, OTTAWA, ON Drwn by Chkd by P.C. B.W. TEST PIT LOCATION PLAN Date Rev. APRIL 6, 15 0 FIGURE 2

10 ATTACHMENT A Record of Test Pit Sheets Report to: J.L. Richards & Associates Limited Project: (April 6, 15)

11 LIST OF ABBREVIATIONS AND TERMINOLOGY SAMPLE TYPES AS auger sample CS chunk sample DO drive open MS manual sample RC rock core ST slotted tube TO thin-walled open Shelby tube TP thin-walled piston Shelby tube WS wash sample PENETRATION RESISTANCE Standard Penetration Resistance, N The number of blows by a 63.5 kg hammer dropped 760 millimetres required to drive a 50 mm drive open sampler for a distance of 300 mm. For split spoon samples where less than 300 mm of penetration was achieved, the number of blows is reported over the sampler penetration in mm. Dynamic Penetration Resistance The number of blows by a 63.5 kg hammer dropped 760 mm to drive a 50 mm diameter, 60 o cone attached to A size drill rods for a distance of 300 mm. WH WR PH rig. Sampler advanced by static weight of hammer and drill rods. Sampler advanced by static weight of drill rods. Sampler advanced by hydraulic pressure from drill SOIL DESCRIPTIONS Relative Density N Value Very Loose 0 to 4 Loose 4 to 10 Compact 10 to 30 Dense 30 to 50 Very Dense over 50 Consistency Undrained Shear Strength (kpa) Very soft 0 to 12 Soft 12 to 25 Firm 25 to 50 Stiff 50 to 100 Very Stiff over 100 LIST OF COMMON SYMBOLS c u undrained shear strength e void ratio C c compression index c v coefficient of consolidation k coefficient of permeability I p plasticity index n porosity u pore pressure w moisture content w L liquid limit w P plastic limit 1 effective angle of friction unit weight of soil 1 unit weight of submerged soil normal stress PM Sampler advanced by manual pressure. SOIL TESTS C consolidation test H hydrometer analysis M sieve analysis MH sieve and hydrometer analysis U unconfined compression test Q undrained triaxial test V field vane, undisturbed and remoulded shear strength

12 PROJECT: LOCATION: See Test Pit Location Plan, Figure 2 DATE OF EXCAVATION: March 12, 15 RECORD OF TEST PIT SHEET 1 OF 1 DATUM: Geodetic TYPE OF EXCAVATOR: Hydraulic Shovel METRES DESCRIPTION SOIL PROFILE STRATA PLOT ELEV. DEPTH (m) SAMPLE NUMBER SHEAR STRENGTH, Cu (kpa) Natural. V - Remoulded. V Wp WATER CONTENT (PERCENT) W Wl ADDITIONAL LAB. TESTING WATER LEVEL IN OPEN TEST PIT OR STANDPIPE INSTALLATION 0 Ground Surface Grey, crushed sand and gravel, trace silt (FILL MATERIAL) Backfilled with excavated soil Brown to dark brown silty fine sand, trace to some gravel, brick, asphalt and metal (FILL MATERIAL) Excavator refusal on probable bedrock TESTPIT LOG 15041_GNT_V01_ GPJ HOULE CHEVRIER FEB 9 11.GDT to 25 LOGGED: ML CHECKED:

13 PROJECT: LOCATION: See Test Pit Location Plan, Figure 2 DATE OF EXCAVATION: March 12, 15 RECORD OF TEST PIT SHEET 1 OF 1 DATUM: Geodetic TYPE OF EXCAVATOR: Hydraulic Shovel METRES DESCRIPTION SOIL PROFILE STRATA PLOT ELEV. DEPTH (m) SAMPLE NUMBER SHEAR STRENGTH, Cu (kpa) Natural. V - Remoulded. V Wp WATER CONTENT (PERCENT) W Wl ADDITIONAL LAB. TESTING WATER LEVEL IN OPEN TEST PIT OR STANDPIPE INSTALLATION 0 Ground Surface Grey, crushed sand and gravel, trace silt (FILL MATERIAL) Backfilled with excavated soil Brown to dark brown silty fine sand, trace to some gravel, brick, asphalt and metal (FILL MATERIAL) Excavator refusal on probable bedrock TESTPIT LOG 15041_GNT_V01_ GPJ HOULE CHEVRIER FEB 9 11.GDT to 25 LOGGED: ML CHECKED:

14 PROJECT: LOCATION: See Test Pit Location Plan, Figure 2 DATE OF EXCAVATION: March 12, 15 RECORD OF TEST PIT SHEET 1 OF 1 DATUM: Geodetic TYPE OF EXCAVATOR: Hydraulic Shovel METRES DESCRIPTION SOIL PROFILE STRATA PLOT ELEV. DEPTH (m) SAMPLE NUMBER SHEAR STRENGTH, Cu (kpa) Natural. V - Remoulded. V Wp WATER CONTENT (PERCENT) W Wl ADDITIONAL LAB. TESTING WATER LEVEL IN OPEN TEST PIT OR STANDPIPE INSTALLATION 0 Ground Surface Grey, crushed sand and gravel, trace silt (FILL MATERIAL) Backfilled with excavated soil Brown to dark brown silty fine sand, trace to some gravel, brick, asphalt and metal (FILL MATERIAL) Excavator refusal on probable bedrock TESTPIT LOG 15041_GNT_V01_ GPJ HOULE CHEVRIER FEB 9 11.GDT to 25 LOGGED: ML CHECKED:

15 PROJECT: LOCATION: See Test Pit Location Plan, Figure 2 DATE OF EXCAVATION: March 12, 15 RECORD OF TEST PIT SHEET 1 OF 1 DATUM: Geodetic TYPE OF EXCAVATOR: Hydraulic Shovel METRES DESCRIPTION SOIL PROFILE STRATA PLOT ELEV. DEPTH (m) SAMPLE NUMBER SHEAR STRENGTH, Cu (kpa) Natural. V - Remoulded. V Wp WATER CONTENT (PERCENT) W Wl ADDITIONAL LAB. TESTING WATER LEVEL IN OPEN TEST PIT OR STANDPIPE INSTALLATION 0 Ground Surface Grey, crushed sand and gravel, trace silt (FILL MATERIAL) Backfilled with excavated soil 1 Brown to dark brown silty fine sand, trace to some gravel, brick, asphalt and metal (FILL MATERIAL) Excavator refusal on probable bedrock TESTPIT LOG 15041_GNT_V01_ GPJ HOULE CHEVRIER FEB 9 11.GDT to 25 LOGGED: ML CHECKED:

16 PROJECT: LOCATION: See Test Pit Location Plan, Figure 2 DATE OF EXCAVATION: March 12, 15 RECORD OF TEST PIT SHEET 1 OF 1 DATUM: Geodetic TYPE OF EXCAVATOR: Hydraulic Shovel METRES DESCRIPTION SOIL PROFILE STRATA PLOT ELEV. DEPTH (m) SAMPLE NUMBER SHEAR STRENGTH, Cu (kpa) Natural. V - Remoulded. V Wp WATER CONTENT (PERCENT) W Wl ADDITIONAL LAB. TESTING WATER LEVEL IN OPEN TEST PIT OR STANDPIPE INSTALLATION 0 Ground Surface Grey, crushed sand and gravel, trace silt (FILL MATERIAL) Backfilled with excavated soil Brown to dark brown silty fine sand, trace to some gravel, brick, asphalt and metal (FILL MATERIAL) Excavator refusal on probable bedrock TESTPIT LOG 15041_GNT_V01_ GPJ HOULE CHEVRIER FEB 9 11.GDT to 25 LOGGED: ML CHECKED: