patersongroup 1.0 Field Observations Consulting Engineers June 9, 2010 File: PG2122-LET.01 Mar Gard Builders 92 Bentley Avenue Ottawa, Ontario K2E 6T9

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1 patersongroup June 9, 2010 Mar Gard Builders 92 Bentley Avenue Ottawa, Ontario K2E 6T9 Attention: Subject: Mr. Tony Miriani Geotechnical Investigation Proposed Commercial Development 4471 to 4487 Innes Road - Ottawa Consulting Engineers 28 Concourse Gate, Unit 1 Ottawa, Ontario Canada, K2E 7T7 Tel: (613) Fax: (613) Geotechnical Engineering Environmental Engineering Hydrogeology Geological Engineering Materials Testing Building Science Dear Sir, Upon your request, Paterson Group (Paterson) conducted a geotechnical investigation for the proposed commercial development to be located at 4471 to 4487 Innes Road, in the City of Ottawa, Ontario. It is understood that the proposed development is to consist of a two (2) storey, commercial building and a four (4) storey commercial/residential building. The following letter report presents our findings and recommendations. 1.0 Field Observations The subject site is currently occupied by two (2) residential dwellings (4479 and 4487 Innes Road) within the east portion of the subject site. The west portion of the subject site is presently undeveloped and grass covered with some trees. Generally, the site is at grade with Innes Road and neighbouring properties. Three (3) boreholes were put down using a truck-mounted auger drill rig operated by a two-person crew and supervised by Paterson personnel. The locations of the boreholes are shown on Drawing PG Test Hole Location Plan attached to this letter. The subsurface profile encountered at the borehole locations, consists either of a topsoil or crushed stone layer at surface followed by a silty sand and gravel with clay fill to a 1.2 to 1.4 m depth followed by a deep silty clay deposit. Fill was not encountered at BH1. Practical refusal to dynamic cone penetration testing (DCPT) was encountered at BH 2 at a 38.7 m depth. Ottawa Kingston North Bay

2 Mr. Tony Mariani Page 2 Groundwater levels were measured on June 2, 2010 within piezometers placed at the borehole locations. The groundwater levels were noted to be at 4.9, 7.4 and 4.8 m depth, respectively. It should be noted that groundwater levels are subject to seasonal fluctuations. Therefore, the groundwater level could vary at the time of construction. For specific details at each test hole location reference should be made to our Soil Profile and Test Data sheets attached to the present letter. Available geological mapping indicates a drift thickness of 30 to 50 m depth and limestone and dolomite interbedded bedrock of the Gull River formation in the immediate area of the subject site. The borehole locations and ground surface elevations were surveyed by Paterson field personnel. Ground surface elevations at the borehole locations were referenced to a temporary benchmark (TBM), consisting of the top of the nail on top of the Shell service station signage located in proximity to the southwest corner of 4471 Innes Road. A geodetic elevation of m is indicated for the TBM by Fairhall, Moffatt and Woodland. The locations of the boreholes are shown on Drawing PG Test Hole Location Plan attached to this letter. 2.0 Geotechnical Assessment Based on the results of our geotechnical investigation, it is expected that the proposed building can be founded by shallow footings provided the bearing resistance values are sufficient for design loads. Alternatively, consideration could be given to a raft foundation or a deep foundation, such as end bearing piles. Due to the underlying sensitive silty clay deposit, a permissible grade raise restriction is required for the subject site. The above and other considerations are further discussed in the following sections. Site Grading and Preparation Topsoil and deleterious fill, such as those containing organic materials, should be stripped from under any building and other settlement sensitive structures. Fill used for grading beneath the proposed building footprints, unless otherwise specified, should consist of clean imported granular fill, such as Ontario Provincial Standard Specifications (OPSS) Granular A or Granular B Type II. The fill should be tested and approved prior to delivery to the site. It should be placed in lifts no greater than 300 mm thick and compacted using suitable compaction equipment for the lift thickness. Fill placed beneath the buildings should be compacted to at least 98% of its standard Proctor maximum dry density (SPMDD). patersongroup

3 Mr. Tony Mariani Page 3 Non-specified existing fill along with site-excavated soil can be used as general landscaping fill where settlement of the ground surface is of minor concern. These materials should be spread in thin lifts and at least compacted by the tracks of the spreading equipment to minimize voids. If these materials are to be used to build up the subgrade level for areas to be paved, they should be compacted in thin lifts to a minimum density of 95% of their respective SPMDD. Non-specified existing fill and site-excavated soils are not suitable for use as backfill against foundation walls, unless a composite drainage system is in place along the foundation walls. Existing foundation walls and other construction debris should be entirely removed from within the proposed building perimeter. Under paved areas, existing construction remnants such as foundation walls should be excavated to a minimum of 1 m below final grade. Foundation Design Shallow Footings Footings, up to 2 m wide, can be designed using a bearing resistance value at serviceability limit states (SLS) of 90 kpa and a factored bearing resistance value at ultimate limit states (ULS) of 175 kpa placed on an undisturbed, stiff silty clay bearing surface at or above geodetic elevation 86.0 m. A geotechnical resistance factor of 0.5 was applied to the above noted bearing resistance value at ULS. The bearing resistance value at SLS will be subjected to potential post-construction total and differential settlements of 25 and 20 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. A permissible grade raise of 0.7 m is recommended for the proposed development. Raft Foundation Consideration can be given to a raft foundation if the continuous design loads exceed the bearing resistance values given above. Preliminary design data is provided below for raft foundation construction based on available data. However, it is recommended that additional soils testing, including consolidation testing, be completed to confirm the provided values if consideration is being given to this method of construction. patersongroup

4 Mr. Tony Mariani Page 4 For our preliminary design calculations, the base of the raft foundation is located at a 2 m depth below the native ground surface elevation. The factored bearing resistance (contact pressure) at ULS can be taken as 75 kpa. A geotechnical resistance factor of 0.5 was applied to the bearing resistance value at ULS. The amount of settlement of the raft slab will be dependent on the sustained raft contact pressure. A bearing resistance value at SLS (contact pressure) of 40 kpa can be used. The loading conditions for the contact pressure are based on sustained loads, that are generally taken to be 100% Dead Load and 50% Live Load. The modulus of subgrade reaction was calculated to be 0.5 MPa/m for a contact pressure of 40 kpa. The design of the raft foundation is required to consider the relative stiffness of the reinforced concrete slab and the supporting bearing medium. Based on the following assumptions for the raft foundation, the proposed building can be designed using the above parameters and a total and differential settlement of 25 and 15 mm, respectively. It is expected that the long-term groundwater level will be at or just below the underside of the raft foundation. The raft slab is impervious and the basement walls will be provided with a perimeter foundation drainage system. Piled Foundation Consideration can be given to using concrete filled steel pipe piles driven to refusal on the bedrock surface. For deep foundations, concrete-filled steel pipe piles are generally utilized in the Ottawa area. Applicable pile resistance at SLS values and factored pile resistance at ULS values are given in Table 1. A resistance factor of 0.4 has been incorporated into the factored ULS values. Note that these are all geotechnical axial resistance values. The geotechnical pile resistance values were estimated using the Hiley dynamic formula, to be confirmed during pile installation with a program of dynamic monitoring. For this project, the dynamic monitoring of two (2) piles would be recommended. This is considered to be the minimum monitoring program, as the piles under shear walls may be required to be driven using the maximum recommended driving energy to achieve the greatest factored resistance at ULS values. Re-striking of all piles at least once will also be required after at least 48 hours have elapsed since initial driving. patersongroup

5 Mr. Tony Mariani Page 5 Table 1 - Pile Foundation Design Data Pile Outside Diameter (mm) Pile Wall Thickness (mm) Geotechnical Axial Resistance SLS (kn) Factored at ULS (kn) Final Set (blows/ 12 mm) Transferr ed Hammer Energy (kj) Design for Earthquakes The proposed buildings can be designed using a seismic site response Class E as defined in the Ontario Building Code 2006 (OBC 2006; Table A) for foundations considered at this site. The soils underlying the site are not susceptible to liquefaction. Slab on Grade Construction/Basement Slab With the removal of all topsoil and deleterious fill, containing organic materials, within the footprint of the proposed buildings, the native soil surface will be considered to be an acceptable subgrade on which to commence backfilling for floor slab construction. It is recommended that the upper 200 mm of sub-slab fill consist of an OPSS Granular A material for slab on grade construction and 19 mm clear stone for the basement slab. All backfill material within the footprint of the proposed buildings should be placed in maximum 300 mm thick loose layers and compacted to at least 98% of its SPMDD. Any soft areas should be removed and backfilled with appropriate backfill material prior to placing any fill. OPSS Granular A or Granular B Type II, with a maximum particle size of 50 mm, are recommended for backfilling below the floor slab. All backfill material within the footprint of the proposed buildings should be placed in maximum 300 mm thick loose layers and compacted to at least 98% of its SPMDD. Pavement Structure Car only parking areas and access lanes are anticipated at this site. The proposed pavement structures are shown in Tables 2 and 3. patersongroup

6 Mr. Tony Mariani Page 6 Table 2 - Recommended Pavement Structure - Car Only Parking Thickness mm Material Description 50 WEAR COURSE - HL-3 or Superpave 12.5 Asphaltic Concrete 150 BASE - OPSS Granular A Crushed Stone 300 SUBBASE - OPSS Granular B Type II SUBGRADE - Either in situ soil, fill or OPSS Granular B Type II material placed over in situ soil or fill. Table 3 - Recommended Pavement Structure - Access Lanes Thickness (mm) Material Description 40 Wear Course - HL-3 or Superpave 12.5 Asphaltic Concrete 50 Binder Course - HL-8 or Superpave 19.0 Asphaltic Concrete 150 BASE - OPSS Granular A Crushed Stone 400 SUBBASE - OPSS Granular B Type II SUBGRADE - Either fill, in situ soil, or OPSS Granular B Type II material placed over in situ soil or fill. Minimum Performance Graded (PG) 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 OPSS Granular B Type II material. The pavement granular base and subbase should be placed in maximum 300 mm thick lifts and compacted to a minimum of 98% of the material s SPMDD using suitable compaction equipment. Satisfactory performance of the pavement structure is largely dependent on keeping the contact zone between the subgrade material and the base stone in a dry condition. Failure to provide adequate drainage under conditions of heavy wheel loading can result in the fine subgrade soil being pumped into the voids in the stone subbase, thereby reducing its load carrying capacity. Consideration should be given to installing subdrains at each catch basin. These drains should be at least 3 m long and should extend in four orthogonal directions or longitudinally when placed along a curb. The subdrain inverts should be approximately 300 mm below subgrade level. The subgrade surface should be crowned to promote water flow to the drainage lines. patersongroup

7 Mr. Tony Mariani Page 7 Foundation Drainage and Backfill It is recommended that a perimeter foundation drainage system be provided for the proposed buildings. The system should consist of a 100 mm to 150 mm diameter perforated corrugated plastic pipe, surrounded on all sides by 150 mm of 10 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 re-use as backfill against the foundation walls, unless a composite drainage system (such as System Platon or Miradrain) is used. Imported granular materials, such as clean sand or OPSS Granular B Type I granular material, should be used 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 of 1.5 m of soil cover alone, or a minimum of 0.6 m of soil cover, in conjunction with foundation insulation, should be provided in this regard. Exterior unheated footings, such as those for 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, such as soil cover of 2.1 m or a combination of soil cover and foundation insulation. Excavation Side Slopes The side slopes of excavations in the soil and fill overburden materials should either be cut back at acceptable slopes or should be retained by shoring systems from the start of the excavation until the structure is backfilled. It is assumed that sufficient room will be available for the greater part of the excavation to be undertaken by open-cut methods (i.e. unsupported excavations). The excavation side slopes above the groundwater level extending to a maximum depth of 3 m should be cut back at 1H:1V or flatter. The flatter slope is required for excavation below groundwater level. The subsoil at this site is considered to be mainly Type 2 and 3 soil according to the Occupational Health and Safety Act and Regulations for Construction Projects. patersongroup

8 Mr. Tony Mariani Page 8 Excavated soil should not be stockpiled directly at the top of excavations and heavy equipment should be kept away from the excavation sides. Slopes in excess of 3 m in height should be periodically inspected by the geotechnical consultant in order to detect if the slopes are exhibiting signs of distress. It is recommended that a trench box be used at all times to protect personnel working in trenches with steep or vertical sides. It is expected that services will be installed by cut and cover methods and excavations will not be left open for extended periods of time. Groundwater Control 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. The rate of flow of groundwater into the excavation through the overburden should be low for expected founding levels and the conditions at this site. It is anticipated that pumping from open sumps will be sufficient to control the groundwater influx through the sides of the excavations. 3.0 Recommendations It is a requirement for the design data provided herein to be applicable that an acceptable materials testing and observation program, including the aspects shown below, 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 3 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. Upon request, a report confirming that these works have been conducted in general accordance with our recommendations could be issued following the completion of a satisfactory materials testing and observation program by the geotechnical consultant. patersongroup

9 Mr. Tony Mariani Page Statement of Limitations The recommendations made in this report are in accordance with our present understanding of the project. Our recommendations should be reviewed when the project drawings and specifications are complete. A soils investigation is a limited sampling of a site. Should any conditions at the site be encountered which differ from those at the test locations, we request that we be notified immediately in order to permit reassessment of our recommendations. The present report applies only to the project described in this document. Use of this report for purposes other than those described herein or by person(s) other than Mar Gard Builders or their agents, without review by this firm for the applicability of our recommendations to the altered use of the report. Best Regards, Paterson Group Inc. David J. Gilbert, P.Eng. Carlos P. Da Silva, P.Eng. Attachments Soil Profile and Test Data sheets Analytical Testing Results Figure 1 - Key Plan Drawing PG Test Hole Location Plan Report Distribution Mar Gard Builders (3 copies) Paterson Group (1 copy) patersongroup

10 patersongroup 28 Concourse Gate, Unit 1, Ottawa, ON K2E 7T7 DATUM REMARKS BORINGS BY Consulting Engineers TBM - Top of nail on top of Shell service station (#1993 Tenth Line Road) signage. Geodetic elevation = m, as provided by Fairhall, Moffatt, Woodland Ltd. CME 55 Power Auger DATE SOIL PROFILE AND TEST DATA Geotechnical Investigation Proposed Commercial Developments - Innes Road Ottawa, Ontario 28 May 2010 FILE NO. HOLE NO. PG2122 BH 1 SOIL DESCRIPTION GROUND SURFACE TOPSOIL 0.15 STRATA PLOT TYPE AU SAMPLE NUMBER % RECOVERY 1 N VALUE or RQD DEPTH 0 ELEV Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction SS Stiff to firm, brown SILTY CLAY - firm and grey by 2.9m depth SS SS SS 5 62 SS End of Borehole 5.18 SS m-June 2/10) Shear Strength (kpa) Undisturbed Remoulded

11 patersongroup 28 Concourse Gate, Unit 1, Ottawa, ON K2E 7T7 DATUM REMARKS BORINGS BY CME 55 Power Auger Consulting Engineers TBM - Top of nail on top of Shell service station (#1993 Tenth Line Road) signage. Geodetic elevation = m, as provided by Fairhall, Moffatt, Woodland Ltd. DATE SOIL PROFILE AND TEST DATA Geotechnical Investigation Proposed Commercial Developments - Innes Road Ottawa, Ontario 28 May 2010 FILE NO. HOLE NO. PG2122 BH 2 SOIL DESCRIPTION GROUND SURFACE FILL: Crushed stone FILL: Brown silty sand with crushed gravel and clay STRATA PLOT TYPE NUMBER SAMPLE % RECOVERY N VALUE or RQD AU 1 SS DEPTH 0 1 ELEV Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction Hard to stiff, brown SILTY CLAY stiff to firm and grey by 2.9m depth Dynamic Cone Penetration Test 5.18m depth. Cone pushed to 9.14m depth Shear Strength (kpa) Undisturbed Remoulded

12 patersongroup 28 Concourse Gate, Unit 1, Ottawa, ON K2E 7T7 DATUM REMARKS BORINGS BY TBM - Top of nail on top of Shell service station (#1993 Tenth Line Road) signage. Geodetic elevation = m, as provided by Fairhall, Moffatt, Woodland Ltd. CME 55 Power Auger Consulting Engineers DATE SOIL PROFILE AND TEST DATA Geotechnical Investigation Proposed Commercial Developments - Innes Road Ottawa, Ontario 28 May 2010 FILE NO. HOLE NO. PG2122 BH 2 SOIL DESCRIPTION GROUND SURFACE STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY N VALUE or RQD DEPTH 11 ELEV Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction Shear Strength (kpa) Undisturbed Remoulded

13 patersongroup 28 Concourse Gate, Unit 1, Ottawa, ON K2E 7T7 DATUM REMARKS BORINGS BY TBM - Top of nail on top of Shell service station (#1993 Tenth Line Road) signage. Geodetic elevation = m, as provided by Fairhall, Moffatt, Woodland Ltd. CME 55 Power Auger Consulting Engineers DATE SOIL PROFILE AND TEST DATA Geotechnical Investigation Proposed Commercial Developments - Innes Road Ottawa, Ontario 28 May 2010 FILE NO. HOLE NO. PG2122 BH 2 SOIL DESCRIPTION GROUND SURFACE STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY N VALUE or RQD DEPTH 22 ELEV Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction Shear Strength (kpa) Undisturbed Remoulded

14 patersongroup 28 Concourse Gate, Unit 1, Ottawa, ON K2E 7T7 DATUM REMARKS BORINGS BY Consulting Engineers Geotechnical Investigation Proposed Commercial Developments - Innes Road Ottawa, Ontario TBM - Top of nail on top of Shell service station (#1993 Tenth Line Road) signage. Geodetic elevation = m, as provided by Fairhall, Moffatt, Woodland Ltd. CME 55 Power Auger DATE SOIL PROFILE AND TEST DATA 28 May 2010 FILE NO. HOLE NO. PG2122 BH 2 SOIL DESCRIPTION GROUND SURFACE STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY N VALUE or RQD DEPTH 33 ELEV Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction End of Borehole Practical refusal to 38.69m depth 1.24m-June 2/10) Shear Strength (kpa) Undisturbed Remoulded

15 patersongroup 28 Concourse Gate, Unit 1, Ottawa, ON K2E 7T7 DATUM REMARKS BORINGS BY CME 55 Power Auger Consulting Engineers TBM - Top of nail on top of Shell service station (#1993 Tenth Line Road) signage. Geodetic elevation = m, as provided by Fairhall, Moffatt, Woodland Ltd. DATE SOIL PROFILE AND TEST DATA Geotechnical Investigation Proposed Commercial Developments - Innes Road Ottawa, Ontario 28 May 2010 FILE NO. HOLE NO. PG2122 BH 3 SOIL DESCRIPTION GROUND SURFACE FILL: Crushed stone FILL: Brown silty sand with gravel Brown SILTY CLAY, trace sand and gravel STRATA PLOT TYPE AU SS SAMPLE NUMBER % RECOVERY N VALUE or RQD DEPTH ELEV Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction Hard to very stiff, brown SILTY CLAY stiff to firm by 2.9m depth - grey by 3.7m depth End of Borehole m-June 2/10) Shear Strength (kpa) Undisturbed Remoulded

16 SITE Source: Google Maps FIGURE 1 KEY PLAN

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