patersongroup 1.0 Field Investigation Consulting Engineers February 8, 2016 Report: PG Doran Contractors Limited 3187 Albion Road South

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1 February 8, 016 Report: PG717-1 Doran Contractors Limited 187 Albion Road South Ottawa, Ontario K1V 8Y Attention: Subject: Mr. Sean Montgomery Geotechnical Investigation Proposed Commercial Development Block 17 - Kanata West Business Park 001 Palladium Drive - Ottawa Consulting Engineers 15 Colonnade Road South Ottawa, Ontario Canada, K7J7E 7 Tel: (61) Fax: (61) 6-6 Geotechnical Engineering Environmental Engineering Hydrogeology Geological Engineering Materials Testing Building Science Archeological Services Dear Sir, Paterson Group (Paterson) was commissioned by Palladium Orthodontics on behalf of 1950 Ontario Inc. to conduct a geotechnical investigation for the proposed commercial development to be located at Block 17 of the Kanata West Business Park at 001 Palladium Drive, in the City of Ottawa, Ontario (refer to Figure 1 - Key Plan in Appendix ). Phase I of the proposed development is understood to consist of a single storey office building of slab-on-grade construction. The remainder of the subject site will consist of car parking and access lanes with landscaping areas. The following letter report presents the geotechnical recommendations pertaining to the design and construction of the subject development as understood at the time of writing this report. 1.0 Field Investigation The field program for the geotechnical investigation was conducted on December, 015. At that time, three boreholes were drilled to a maximum 6.7 m depth. The boreholes were completed with a low clearance track-mounted auger drill rig operated by a two-person crew. All fieldwork was conducted under the full-time supervision of field personnel under the direction of a senior engineer from the geotechnical department. Ottawa Kingston North Bay

2 Page The test hole locations were selected by Paterson and surveyed in the field by Stantec Geomatics. The ground surface elevations at the test hole locations are understood to be referenced to a geodetic datum. The locations and ground surface elevations of the test holes are presented on Drawing PG Test Hole Location Plan..0 Field Observations Generally, the ground surface across the subject site is a relatively flat field covered with grassed areas and overgrown vegetation. A large ditch of approximately m depth extends along the north property boundary of the subject site. Generally, the subsurface profile encountered at the test hole locations consists of topsoil underlain by a firm to stiff silty clay to clayey silt layer extending to a depth of approximately to 6 m below existing grade. A compact to dense glacial till, consisting of a silty sand to sandy silt with gravel, cobbles and boulders was noted below the silty clay to clayey silt layer within the boreholes. Practical refusal to the DCPT was reached at a depth of 7.09 m at BH 1. Refer to the Soil Profile and Test Data sheets in Appendix 1 for specific details of the soil profiles encountered at each test hole location. Based on available geological mapping, the site is located in an area where the bedrock consists of interbedded limestone and shale of the Verulam formation in the north and interbedded limestone and dolomite of the Gull River formation to the south. The bedrock surface is expected at depths ranging from 5 to 5 m. On January 6, 016, groundwater levels were measured in piezometers installed at the borehole locations. The measured groundwater levels are presented on the Soil Profile and Test Data sheets in Appendix 1. Based on field observations, the long-term groundwater level is anticipated at a.0 to.5 m depth below existing ground surface. Groundwater levels are subject to seasonal fluctuations and could vary at the time of construction. Table 1 - Summary of Groundwater Levels Borehole Number Ground Surface Elevation (m) Measured Groundwater Level (m) Depth Elevation Date BH January 6, 016 BH January 6, 016 BH January 6, 016 Note: Ground surface elevations at the test hole locations were provided by Stantec.

3 Page.0 Geotechnical Assessment From a geotechnical perspective, the subject site is adequate for the proposed development. The proposed building is expected to be founded by conventional shallow footings placed on an undisturbed, firm to stiff silty clay to clayey silt bearing surface. Due to the presence of a silty clay layer, a grade raise restriction has been provided. The above and other considerations are further discussed in the following sections. Site Grading and Preparation Topsoil, deleterious fill and soils containing significant amounts of organics, should be stripped from under any buildings and other settlement sensitive structures. All bearing surfaces and subgrade soils should be protected to ensure an undisturbed surface is maintained during site preparation activities. Fill placed for grading beneath the proposed building footprint, unless otherwise specified, should consist of clean imported granular fill, such as Ontario Provincial Standard Specifications (OP) Granular A or Granular B Type II. The fill should be tested and approved prior to delivery to the site. The fill material should be placed in maximum 00 mm thick lifts and compacted to a minimum of 98% of the standard Proctor maximum dry density (SPMDD). Non-specified existing fill along with site-excavated soil can be placed as general landscaping fill where surface settlement is a minor concern. The material should be spread in thin lifts and at least compacted by the tracks of the spreading equipment to minimize voids. If the material is to be placed to increase the subgrade level for areas to be paved, the material should be compacted in maximum 00 mm thick loose lifts and compacted to a minimum density of 95% of the SPMDD. Non-specified existing fill and site-excavated soils are not suitable for placement as backfill against foundation walls, unless tested and approved for placement or placed in conjunction with a geocomposite drainage membrane, such as Miradrain GN or Delta Drain Foundation Design Footings placed on a stiff, silty clay to clayey silt bearing surface can be designed using a bearing resistance value at serviceability limit states (SLS) of 150 kpa and a factored bearing resistance value at ultimate limit states (ULS) of 50 kpa. A geotechnical resistance factor of 0.5 was applied to the above-noted bearing resistance value at ULS.

4 Page Footings designed using the above-noted bearing resistance value at SLS will be subjected to potential post-construction total and differential settlements of 5 and 0 mm, respectively. An undisturbed soil bearing surface consists of a surface from which all topsoil and deleterious materials, such as loose, frozen or disturbed soil, whether in situ or not, have been removed, in the dry, prior to the placement of concrete for footings. The bearing medium under footing-supported structures should be provided with adequate lateral support with respect to excavations and different foundation levels. Above the groundwater level, adequate lateral support is provided to a compact glacial till when a plane extending horizontally and vertically from the footing perimeter at a minimum of 1.5H:1V passing through in situ soil or engineered fill. Permissible Grade Raise Recommendations Based on the existing borehole coverage and results of the undrained shear strength testing completed within the underlying cohesive soils, a permissible grade raise restriction of.0 m is recommended to be implemented for areas where foundations are placed over the silty clay deposit. A post-development groundwater lowering of 0.5 m was considered in our permissible grade raise restriction calculations. Design for Earthquakes The proposed building can be designed to a seismic site response Class D as defined in the Ontario Building Code 01 (OBC 01; Table.1.8..A). A higher site class, such as Class C could be applicable for foundation design. However, the higher site class would have to be determined based on site-specific shear wave velocity testing. The soils underlying the site are not susceptible to liquefaction.. Slab-on Grade Construction With the removal of all topsoil, soils containing significant amounts of organics or deleterious fill within the proposed building footprint, the native soil surface will be considered an acceptable subgrade surface on which to commence backfilling for floor slab construction. Provision should be provided for proof-rolling the soil subgrade with heavy vibratory compaction equipment prior to placing any fill. Any soft areas should be removed and backfilled with appropriate backfill material. OP Granular B Type II is recommended for backfilling below the floor slab. The upper 00 mm of sub-slab backfill is recommended to consist of an OP Granular A crushed stone.

5 Page 5 Pavement Structure For design purposes, the pavement structure presented in the following tables could be designed for car only parking areas and access lanes. Table - Recommended Flexible Pavement Structure - Car Only Parking Areas Thickness (mm) Material Description 50 Wear Course - HL- or Superpave 1.5 Asphaltic Concrete 150 BASE - OP Granular A Crushed Stone 00 SUBBASE - OP Granular B Type II SUBGRADE - Either fill, in situ soil or OP Granular B Type I or II material placed over in situ soil or fill Table - Recommended Flexible Pavement Structure - Access Ramp/Lane Thickness (mm) Material Description 0 Wear Course - HL- or Superpave 1.5 Asphaltic Concrete 50 Binder Course - HL-8 or Superpave 19.0 Asphaltic Concrete 150 BASE - OP Granular A Crushed Stone 00 SUBBASE - OP Granular B Type II SUBGRADE - Either fill, in situ soil or OP Granular B Type I or II material placed over in situ soil or fill Minimum Performance Graded (PG) 58- asphalt cement should be used for this project. If soft spots develop in the subgrade during compaction or due to construction traffic, the affected areas should be excavated and replaced with OP Granular B Type II material. The pavement granular base and subbase should be placed in maximum 00 mm thick lifts and compacted to a minimum of 98% of the SPMDD.

6 Page 6 Pavement Structure Drainage The pavement structure performance is dependent on the moisture condition at the contact zone between the subgrade material and granular base. Failure to provide adequate drainage under conditions of heavy wheel loading could result in the subgrade fines being pumped into the stone subbase voids, thereby reducing the load bearing capacity. Due to the impervious nature of the subgrade materials consideration should be provided to installing subdrains during the pavement construction. The subdrains should extend in four orthogonal directions and longitudinally when placed along a curb. The clear crushed stone surrounding the drainage lines or the pipe, should be wrapped with suitable filter cloth. The subdrain inverts should be approximately 00 mm below subgrade level and placed in accordance with City of Ottawa standard drawing R1. The subgrade surface should be shaped to promote water flow to the drainage lines.

7 Page 7.0 Design and Construction Precautions Foundation Drainage and Backfill A perimeter foundation drainage system is recommended to be provided for the proposed structure. The system should consist of a 150 mm diameter perforated corrugated plastic pipe, surrounded on all sides by 150 mm of 19 mm clear crushed stone, placed at the footing level around the exterior perimeter of the structure. The pipe should have a positive outlet, such as a gravity connection to the storm sewer. Backfill against the exterior sides of the foundation walls should consist of free-draining non frost susceptible granular materials. The greater part of the site excavated materials will be frost susceptible and, as such, are not recommended for placement as backfill against the foundation walls unless used in conjunction with a composite drainage system, such as Delta Drain 6000 or Miradrain GN. Imported granular materials, such as clean sand or OP Granular B Type I granular material, should be placed for this purpose. Protection of Footings Against Frost Action Perimeter footings of heated structures are required to be insulated against the deleterious effects of frost action. A minimum 1.5 m thick soil cover (or equivalent) should be provided. Exterior unheated footings, such as isolated exterior piers, are more prone to deleterious movement associated with frost action than the exterior walls of the structure proper and require additional protection. The recommended minimum thickness of soil cover is.1 m (or equivalent). Temporary Side Slopes The excavation side slopes in the overburden materials should either be excavated to acceptable slopes or retained by shoring systems from the beginning of the excavation until the structure is backfilled. The excavation side slopes above the groundwater level extending to a maximum depth of m should be excavated at 1.5H:1V or shallower. A shallower slope is required for excavation below groundwater level. The subsurface soil is considered to be mainly Type and soil according to the Occupational Health and Safety Act and Regulations for Construction Projects.

8 Page 8 Excavated soil should not be stockpiled directly at the top of excavations and heavy equipment should maintain safe working distance from the excavation sides. Slopes in excess of m in height should be periodically inspected by the geotechnical consultant in order to detect if the slopes are exhibiting signs of distress. A trench box is recommended to be installed at all times to protect personnel working in trenches with steep or vertical sides. Services are expected to be installed by cut and cover methods and excavations should not remain exposed for extended periods of time. Pipe Bedding Bedding and backfill materials should be in accordance with City of Ottawa standards and specifications. The pipe bedding for sewer and water pipes should consist of at least 150 mm of OP Granular A material. Where the bedding is located within soft to firm grey silty clay, the thickness of the bedding material should be increased to a minimum of 00 mm, which is a recommended deviation from specifications provided in City of Ottawa standard drawing S6. The material should be placed in maximum 00 mm thick lifts and compacted to a minimum of 95% of the SPMDD. The bedding material should extend at a minimum to the spring line of the pipe. The cover material, which should consist of OP Granular A, should extend from the spring line of the pipe to a minimum of 00 mm above the obvert of the pipe. The material should be placed in maximum 00 mm thick lifts and compacted to a minimum of 95% of the SPMDD. Generally, the dry brown silty clay could be placed above the cover material if the excavation and backfilling operations are completed in dry and above freezing weather conditions. The wet silty clay materials could be difficult to place and compact, due to the high water content. Where hard surface areas are considered above the trench backfill, the trench backfill material within the frost zone (about 1.8 m below finished grade) should consist of the soils exposed at the trench walls to minimize differential frost heaving. The trench backfill should be placed in maximum 00 mm thick loose lifts and compacted to a minimum of 95% of the SPMDD.

9 Page 9 To reduce long-term lowering of the groundwater level, clay seals should be provided in the service trenches. The seals should be a minimum of 1.5 m long (in the trench direction) and should extend from trench wall to trench wall. Generally, the seals should extend from the frost line and fully penetrate the bedding, subbedding and cover material. The barriers should consist of relatively dry and compactable brown silty clay placed in maximum 5 mm thick loose layers and compacted to a minimum of 95% of the SPMDD. The clay seals should be placed at the site boundaries, roadway intersections and at a maximum distance of every 50 m in the service trenches. Groundwater Control for Building Construction The contractor should be prepared to direct water away from all bearing surfaces and subgrades, regardless of the source, to prevent disturbance to the founding medium. A temporary MOE permit to take water (PTTW) will be required, if more than 50,000 L/day are to be pumped during the construction phase. A minimum of four to five months should be allocated for completion of the application and issuance of the permit by the MOE. Winter Construction Precautions should be provided if winter construction is considered for this project. The subsurface conditions mainly consist of frost susceptible materials. In presence of water and freezing conditions, ice could form within the soil mass. Heaving and settlement upon thawing could occur. In the event of construction during below zero temperatures, the founding stratum should be protected from freezing temperatures by the installation of straw, propane heaters, tarpaulins or other suitable means. Any excavation base should be insulated from subzero temperatures immediately upon exposure and until such time as heat is adequately supplied to the building and the footings are protected with sufficient soil cover to prevent freezing at founding level. The trench excavations should be constructed in a manner to avoid the introduction of frozen materials, snow or ice into the trenches.

10 Page 10 Corrosion Potential and Sulphate The analytical test results indicate the sulphate content is less than 0.1%. The result is indicative that Type 10 Portland cement. The chloride content and the ph of the sample are indicative of non significant factors in creating a corrosive environment for exposed ferrous metals, whereas the resistivity is indicative of a low corrosive environment. Table - Corrosion Potential Parameter Laboratory Results Threshold Commentary BH Chloride <5 ìg/g Chloride content less than 00 mg/g Negligible concern ph 7.67 ph value less than 5.0 Neutral Soil Resistivity 77.9 ohm.m Resistivity greater than 1,500 ohm.cm Low Corrosion Potential Sulphate 7 ìg/g Sulphate value greater than 1 mg/g Negligible Concern

11 Page Recommendations For the foundation design data provided to be applicable, a materials testing and observation services program is required to be completed. The following aspects should be performed by the geotechnical consultant: Observation of all bearing surfaces prior to the placement of concrete. Sampling and testing of the concrete and fill materials used. Periodic observation of the condition of unsupported excavation side slopes in excess of m in height, if applicable. Observation of all subgrades prior to backfilling. Field density tests to determine the level of compaction achieved. Sampling and testing of the bituminous concrete including mix design reviews. A report confirming the construction has been conducted in general accordance with the recommendations could be issued, upon request, following the completion of a satisfactory materials testing and observation program by the geotechnical consultant.

12 Page Statement of Limitations The recommendations provided in the report are in accordance with Paterson s present understanding of the project. Paterson request permission to review the recommendations when the drawings and specifications are completed. A soils investigation is a limited sampling of a site. Should any conditions at the site be encountered which differ from the test locations, Paterson requests immediate notification to permit reassessment of the recommendations. The recommendations provided should only be used by the design professionals associated with this project. The recommendations are not intended for contractors bidding on or constructing the project. The latter should evaluate the factual information provided in the report. The contractor should also determine the suitability and completeness for the intended construction schedule and methods. Additional testing may be required for the contractors purpose. The present report applies only to the project described in the report. The use of the report for purposes other than those described above or by person(s) other than Doran Contractors, Palladium Orthodontics, 1950 Ontario Inc. or their agents is not authorized without review by Paterson. Best Regards, Paterson Group Inc. Joe Forsyth, P.Eng David J. Gilbert. P.Eng. Attachments Soil Profile and Test Data sheets Figure 1 - Key Plan Drawing PG Test Hole Location Plan Report Distribution Doran Contractors ( copies ) Paterson Group (1 copy)

13 15 Colonnade Road South, Ottawa, Ontario KE 7J5 DATUM REMARKS BORINGS BY Consulting Engineers Ground surface elevations provided by Stantec Geomatics Ltd. SOIL PROFILE AND TEST DATA Geotechnical Investigation Prop. Orthodontics/Office Building - Block 17 Palladium Drive, Ottawa, Ontario FILE NO. HOLE NO. PG717 CME 55 Power Auger DATE December, 015 BH 1 SOIL DESCRIPTION GROUND SURFACE TOPSOIL 0.0 STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY N VALUE or RQD DEPTH (m) 0 ELEV. (m) Pen. Resist. Blows/0.m 50 mm Dia. Cone Water Content % Piezometer Construction AU Very stiff to stiff, brown SILTY CLAY, some sand G G firm and grey by.m depth 5.18 G GLACIAL TILL: Compact, grey silty sand with clay, gravel and cobbles Dynamic Cone Penetration Test commenced at 6.70m depth Inferred GLACIAL TILL End of Borehole Practical DCPT refusal at 7.09m depth 1.7m-Jan. 6, 016) Shear Strength (kpa) Undisturbed Remoulded

14 15 Colonnade Road South, Ottawa, Ontario KE 7J5 DATUM REMARKS BORINGS BY Consulting Engineers Ground surface elevations provided by Stantec Geomatics Ltd. SOIL PROFILE AND TEST DATA Geotechnical Investigation Prop. Orthodontics/Office Building - Block 17 Palladium Drive, Ottawa, Ontario FILE NO. HOLE NO. PG717 CME 55 Power Auger DATE December, 015 BH SOIL DESCRIPTION GROUND SURFACE TOPSOIL 0.0 STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY N VALUE or RQD DEPTH (m) 0 ELEV. (m) 10.5 Pen. Resist. Blows/0.m 50 mm Dia. Cone Water Content % Piezometer Construction Very stiff, brown SILTY CLAY, some sand G GLACIAL TILL: Brown to grey clayey sand to silty sand with gravel and cobbles End of Borehole m-Jan. 6, 015) Shear Strength (kpa) Undisturbed Remoulded

15 15 Colonnade Road South, Ottawa, Ontario KE 7J5 DATUM REMARKS BORINGS BY CME 55 Power Auger Consulting Engineers Ground surface elevations provided by Stantec Geomatics Ltd. SOIL PROFILE AND TEST DATA Geotechnical Investigation Prop. Orthodontics/Office Building - Block 17 Palladium Drive, Ottawa, Ontario DATE December, 015 FILE NO. HOLE NO. PG717 BH SOIL DESCRIPTION GROUND SURFACE TOPSOIL 0.15 STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY N VALUE or RQD DEPTH (m) 0 ELEV. (m) Pen. Resist. Blows/0.m 50 mm Dia. Cone Water Content % Piezometer Construction G Very stiff to stiff, brown SILTY CLAY, some sand G G grey by.m depth G G GLACIAL TILL: Grey sandy silt with clay, gravel and cobbles 6.70 End of Borehole 7 8 6, 015) Shear Strength (kpa) Undisturbed Remoulded

16 15 Colonnade Road South, Ottawa, Ontario KE 7J5 Consulting Engineers SOIL PROFILE AND TEST DATA Geotechnical Investigation Proposed Commercial Development - Huntmar Road Ottawa, Ontario DATUM Ground surface elevations provided by Stantec Geomatics Ltd. FILE NO. REMARKS HOLE NO. BORINGS BY CME 55 Power Auger DATE January 1, 01 PG115 BH 6 SOIL DESCRIPTION GROUND SURFACE TOPSOIL 0.5 STRATA PLOT TYPE AU SAMPLE NUMBER 1 % RECOVERY N VALUE or RQD DEPTH (m) 0 ELEV. (m) 10.8 Pen. Resist. Blows/0.m 50 mm Dia. Cone Water Content % Piezometer Construction Very stiff to stiff, brown SILTY CLAY grey-brown by 1.m depth Grey-brown CLAYEY SILT 5.9 GLACIAL TILL: Grey-brown clayey silt with gravel, cobbles, trace 6.5 boulders End of Borehole Practical refusal to augering at 6.5mn depth depth based on field observations) Shear Strength (kpa) Undisturbed Remoulded

17 SITE Source: City of Ottawa Emaps. FIGURE 1 KEY PLAN

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