As part of Paterson s review, the following drawings prepared by Chmiel Architects and Novatech Engineering Consultants were reviewed:

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1 August 22, 2015 P3584-LET.01 Jones Lang LaSalle Real Estate 275 Slater Street, Suite 1004 Ottawa, Ontario K1P 5H9 Consulting Engineers 154 Colonnade Road South Ottawa, Ontario K2E 7J5 Tel: (613) Fax: (613) eotechnical Engineering Environmental Engineering Hydrogeology eological Engineering Materials Testing Building Science Archaeological Services Attention: Subject: Mr. Peter Miller eotechnical Review Proposed Asphalt Parking Area Canada Post - Building F Site 2785 Riverside Drive - Ottawa Dear Sir, Further to your request and authorization, Paterson roup (Paterson) completed a geotechnical review for the proposed asphalt parking area to be located at the location of the previously demolished Building F site. The following letter report presents the geotechnical findings and recommendations pertaining to the design and construction of the proposed parking lot area and underground services as understood at the time of writing the report. 1.0 Background Information The proposed asphalt parking area is understood to be constructed along the north side of Brookfield Road within the footprint and surrounding grounds of the previous Building F. The proposed site is currently vacant. As part of Paterson s review, the following drawings prepared by Chmiel Architects and Novatech Engineering Consultants were reviewed: Chmiel Architects - CPC Parking Lot - Site Plan - Drawing No. SP-01 - Revision 3 dated June 30, Novatech Engineering Consultants - Site Servicing, rading, and Stormwater Management Plan - Drawing No SS - Revision dated June 30, Ottawa Kingston North Bay

2 Mr. Peter Miller Page 2 P3584-LET eotechnical Review Field Program Four test pits were placed within the proposed parking area on August 12, The test pits were conducted by means of a rubber tire backhoe under the full time supervision of senior Paterson personnel. The test pits, which were numbered TP1 to TP4, were terminated at depths ranging from 2.0 to 3.0 m below the existing grade. The depths at which the grab samples were obtained from the test holes are presented as on the Soil Profile and Test Data sheets. The test pits were placed in a manner to provide general coverage of the proposed parking area with consideration for underground utilities and site features. The approximate locations of the test holes are presented in Drawing P Test Hole Location Plan attached. Surface Conditions The existing ground surface in the area is typically at grade with the surrounding roadways. The previous building location currently consists of a graded area consisting of granular material with associated landscaped and asphalt parking areas. Subsurface Profile enerally, the subsurface profile at the test pit locations encountered a layer of fill material consisting of crushed concrete, sand, gravel, various debris overlying a brown silty clay to clayey silt deposit. All test pits were terminated in a native brown silty clay. roundwater The infiltration rate was observed during the test pit program. During the investigation, all the test pits were noted to be dry upon completion. However, groundwater levels are expected to fluctuate throughout the year with seasonal variations and could vary at the time of construction. 3.0 eotechnical Assessment From a geotechnical perspective, the subject site is adequate for the proposed asphalt parking area. The design recommendations and construction precautions are presented in the following sections.

3 Mr. Peter Miller Page 3 P3584-LET.01 The existing tunnel, along the northeastern portion of the subject site, which has not been infilled with concrete, should be reviewed by a structural engineer or backfilled with concrete prior to the proposed parking area being constructed to ensure the existing tunnel can support the expected vehicle traffic. Site rading and Preparation Topsoil, deleterious fill and soils containing significant amounts of organics or soft areas, should be stripped from under the proposed pavement structure or undergound services. All bearing surfaces and subgrade soils should be protected to ensure an undisturbed surface is maintained during site preparation activities. The existing fill layer should be reviewed by the geotechnical consultant, once a large area of the fill is exposed to determine if the existing fill material will provide an acceptable subgrade surface on which to commence backfilling for the proposed pavement structure. Fill placed for grading beneath the proposed pavement structure should consist, unless otherwise specified, of clean imported granular fill, such as Ontario Provincial Standard Specifications (OPSS) ranular A or ranular B Type II. ranular material should be tested and approved prior to delivery to the site. The fill should be placed in lifts of 300 mm thick or less 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 settlement of the ground surface is of minor concern. The fill materials should be spread in thin lifts and at a minimum 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 fill should be compacted in maximum 300 mm lifts and compacted to 95% of SPMDD. Protection of Subgrade Surface The site grading and preparation should consist of stripping the soils containing significant amounts of organic materials. The contractor should provide appropriate precautions to avoid disturbing the subgrade surfaces from construction and worker traffic. Disturbance of the subgrade may result in sub-excavating the disturbed material and place additional engineered fill. The exposed subgrade surface should be protected with a sufficient thickness of select subgrade material, engineered fill or lean concrete mud slab that can sustain vehicle traffic based on the weather conditions at the time of construction.

4 Mr. Peter Miller Page 4 P3584-LET.01 Pavement Structure The pavement structure presented in the following tables should be used for the design of car parking areas. Table 1 - Recommended Pavement Structure - Car Only Parking Thickness mm Material Description 50 WEAR COURSE - HL-3 or Superpave 12.5 Asphaltic Concrete 150 BASE - OPSS ranular A Crushed Stone 300 SUBBASE - OPSS ranular B Type II Ontario Traffic Category A SUBRADE - Either in situ soil, fill or OPSS ranular B Type II material placed over in situ soil or fill. Table 2 - 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 ranular A Crushed Stone Ontario Traffic Category B 400 SUBBASE - OPSS ranular B Type II SUBRADE - Either in situ soils, existing fill approved by the geotechnical consultant or OPSS ranular B Type I or II material placed over in situ soil. Minimum Performance raded (P) 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 ranular 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 SPMDD using suitable compaction equipment.

5 Mr. Peter Miller Page 5 P3584-LET.01 Where the proposed pavement structure meets the existing asphalt surface, the following recommendations should be followed: A 300 mm wide section of the existing asphalt roadway should be saw cut from the existing pavement edge to provide a sound surface to abut the proposed pavement structure. It is recommended to mill a minimum 40 mm deep section of the existing asphalt within 300 mm of the saw cut edge. The proposed pavement structure subbase materials should be tapered no greater than 3H:1V to meet the existing subbase materials. Clean existing granular road subbase materials can be reused upon assessment by the geotechnical consultant at the time of excavation (construction) as to its suitability. 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 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 300 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. Pipe Bedding and Backfill 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 OPSS ranular A material. Where the bedding is located within the firm grey silty clay, the thickness of the bedding material should be increased to a minimum of 300 mm, which is a recommended deviation from specifications provided in City of Ottawa standard drawing S6. The material should be placed in maximum 300 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.

6 Mr. Peter Miller Page 6 P3584-LET.01 The cover material, which should consist of OPSS ranular A, should extend from the spring line of the pipe to a minimum of 300 mm above the obvert of the pipe. The material should be placed in maximum 300 mm thick lifts and compacted to a minimum of 95% of the SPMDD. enerally, the dry brown silty clay could be place 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 300 mm thick loose lifts and compacted to a minimum of 95% of the SPMDD. To reduce long-term lowering of the groundwater level, clay seals should be provided in the service trenches, if the service trench is placed within the native silty clay. The seals should be a minimum of 1.5 m long (in the trench direction) and should extend from trench wall to trench wall. enerally, 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 225 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. Winter Construction The subsurface conditions mostly 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. If winter construction is considered for this project, construction activities should proceed with caution. 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. All excavation bases should be insulated from sub-zero 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.

7 Mr. Peter Miller Page 7 P3584-LET.01 The trench excavations should be constructed in a manner that should avoid the introduction of frozen materials into the trenches. As well, pavement construction is difficult during winter. The subgrade consists of frost susceptible soils which will experience total and differential frost heaving as the construction is completed. In addition, the introduction of frost, snow or ice into the pavement materials, which is difficult to avoid, could adversely affect the performance of the pavement structure. Additional information could be provided, if required.

8 Mr. Peter Miller Page 8 P3584-LET Recommendations A materials testing and observation services program is a requirement for the provided foundation design data to be applicable. The following aspects of the program should be performed by the geotechnical consultant: Observation of proof rolling subgrade layers with heavy compaction equipment. Observation of all bearing surfaces prior to the placement of asphalt/concrete or site services. 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. A report confirming the construction has been completed in general accordance with the recommendations could be issued, upon request, following the completion of a satisfactory material testing and observation program by the geotechnical consultant.

9 Mr. Peter Miller Page 9 P3584-LET Statement of Limitations The recommendations made in this memo 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 Jones Lang LaSalle Real Estate or their agent(s) is not authorized without review by this firm for the applicability of our recommendations to the altered use of the report. We trust that this information satisfies your immediate request. Best Regards, Paterson roup Inc. Michael Killam, B.Eng. Joe Forsyth, P.Eng. Attachments Soil Profile and Test Data Sheets Symbols and Terms Key Plan Drawing P Test Hole Location Plan

10 Engineers 154 Colonnade Road South, Ottawa, Ontario K2E 7J5 DATUM REMARKS Consulting eotechnical Investgation Proposed Parking Lot Riverside Drive Ottawa, Ontario TBM - Top spindle of fire hydrant located near the southeast corner of subject site. eodetic elevation = 79.03m. Backhoe SOIL PROFILE AND TEST DATA FILE NO. HOLE NO. BORINS BY TP 1 DATE August 12, 2015 P3584 SOIL DESCRIPTION ROUND SURFACE FILL: Sand and gravel 0.10 STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY 1 N VALUE or RQD DEPTH (m) 0 ELEV. (m) Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction FILL: Sand, gravel and cobbles with computer wires and pieces, insulation, brick and construction material FILL: Brown sand, some gravel and cobbles Brown SILTY CLAY, some sand End of Test Pit (TP dry upon completion) Shear Strength (kpa) Undisturbed Remoulded

11 154 Colonnade Road South, Ottawa, Ontario K2E 7J5 DATUM REMARKS BORINS BY Consulting Engineers SOIL PROFILE AND TEST DATA eotechnical Investgation Proposed Parking Lot Riverside Drive Ottawa, Ontario TBM - Top spindle of fire hydrant located near the southeast corner of subject site. eodetic elevation = 79.03m. Backhoe DATE August 12, 2015 FILE NO. HOLE NO. P3584 TP 2 SOIL DESCRIPTION ROUND SURFACE STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY N VALUE or RQD DEPTH (m) 0 ELEV. (m) Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction FILL: Sand and gravel FILL: Wood with sand, gravel, steel, crushed concrete, brick and insulation Brown SILTY CLAY 3 End of Test Pit (TP dry upon completion) Shear Strength (kpa) Undisturbed Remoulded

12 Engineers 154 Colonnade Road South, Ottawa, Ontario K2E 7J5 DATUM REMARKS Consulting eotechnical Investgation Proposed Parking Lot Riverside Drive Ottawa, Ontario TBM - Top spindle of fire hydrant located near the southeast corner of subject site. eodetic elevation = 79.03m. Backhoe SOIL PROFILE AND TEST DATA FILE NO. HOLE NO. BORINS BY TP 3 DATE August 12, 2015 P3584 SOIL DESCRIPTION ROUND SURFACE FILL: ravel with sand 0.15 STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY 1 N VALUE or RQD DEPTH (m) 0 ELEV. (m) Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction FILL: Brick, crushed stone, plastic, paper, wires, insulation, some sand and gravel FILL: Brown sand, some asphalt and brick Brown SILTY CLAY End of Test Pit (TP dry upon completion) Shear Strength (kpa) Undisturbed Remoulded

13 154 Colonnade Road South, Ottawa, Ontario K2E 7J5 DATUM REMARKS Consulting Engineers SOIL PROFILE AND TEST DATA eotechnical Investgation Proposed Parking Lot Riverside Drive Ottawa, Ontario TBM - Top spindle of fire hydrant located near the southeast corner of subject site. eodetic elevation = 79.03m. Backhoe DATE August 12, 2015 FILE NO. HOLE NO. BORINS BY TP 4 P3584 SOIL DESCRIPTION ROUND SURFACE STRATA PLOT TYPE SAMPLE NUMBER % RECOVERY N VALUE or RQD DEPTH (m) 0 ELEV. (m) Pen. Resist. Blows/0.3m 50 mm Dia. Cone Water Content % Piezometer Construction FILL: ravel with sand FILL: Crushed concrete with sand, gravel, brick, insulation, wires FILL: Dark brown sand with gravel and asphalt Brown SILTY CLAY End of Test Pit (TP dry upon completion) Shear Strength (kpa) Undisturbed Remoulded

14 SYMBOLS AND TERMS SOIL DESCRIPTION Behavioural properties, such as structure and strength, take precedence over particle gradation in describing soils. Terminology describing soil structure are as follows: Desiccated - having visible signs of weathering by oxidation of clay minerals, shrinkage cracks, etc. Fissured - having cracks, and hence a blocky structure. Varved - composed of regular alternating layers of silt and clay. Stratified - composed of alternating layers of different soil types, e.g. silt and sand or silt and clay. Well-raded - Having wide range in grain sizes and substantial amounts of all intermediate particle sizes (see rain Size Distribution). Uniformly-raded - Predominantly of one grain size (see rain Size Distribution). The standard terminology to describe the strength of cohesionless soils is the relative density, usually inferred from the results of the Standard Penetration Test (SPT) N value. The SPT N value is the number of blows of a 63.5 kg hammer, falling 760 mm, required to drive a 51 mm O.D. split spoon sampler 300 mm into the soil after an initial penetration of 150 mm. Relative Density N Value Relative Density % Very Loose <4 <15 Loose Compact Dense Very Dense >50 >85 The standard terminology to describe the strength of cohesive soils is the consistency, which is based on the undisturbed undrained shear strength as measured by the in situ or laboratory vane tests, penetrometer tests, unconfined compression tests, or occasionally by Standard Penetration Tests. Consistency Undrained Shear Strength (kpa) N Value Very Soft <12 <2 Soft Firm Stiff Very Stiff Hard >200 >30

15 SYMBOLS AND TERMS (continued) SOIL DESCRIPTION (continued) Cohesive soils can also be classified according to their sensitivity. The sensitivity is the ratio between the undisturbed undrained shear strength and the remoulded undrained shear strength of the soil. Terminology used for describing soil strata based upon texture, or the proportion of individual particle sizes present is provided on the Textural Soil Classification Chart at the end of this information package. ROCK DESCRIPTION The structural description of the bedrock mass is based on the Rock Quality Designation (RQD). The RQD classification is based on a modified core recovery percentage in which all pieces of sound core over 100 mm long are counted as recovery. The smaller pieces are considered to be a result of closelyspaced discontinuities (resulting from shearing, jointing, faulting, or weathering) in the rock mass and are not counted. RQD is ideally determined from NXL size core. However, it can be used on smaller core sizes, such as BX, if the bulk of the fractures caused by drilling stresses (called mechanical breaks ) are easily distinguishable from the normal in situ fractures. RQD % ROCK QUALITY Excellent, intact, very sound ood, massive, moderately jointed or sound Fair, blocky and seamy, fractured Poor, shattered and very seamy or blocky, severely fractured 0-25 Very poor, crushed, very severely fractured SAMPLE TYPES SS - Split spoon sample (obtained in conjunction with the performing of the Standard Penetration Test (SPT)) TW - Thin wall tube or Shelby tube PS - Piston sample AU - Auger sample or bulk sample WS - Wash sample RC - Rock core sample (Core bit size AXT, BXL, etc.). Rock core samples are obtained with the use of standard diamond drilling bits.

16 SYMBOLS AND TERMS (continued) RAIN SIZE DISTRIBUTION MC% - Natural moisture content or water content of sample, % LL - Liquid Limit, % (water content above which soil behaves as a liquid) PL - Plastic limit, % (water content above which soil behaves plastically) PI - Plasticity index, % (difference between LL and PL) Dxx - rain size which xx% of the soil, by weight, is of finer grain sizes These grain size descriptions are not used below mm grain size D10 - rain size at which 10% of the soil is finer (effective grain size) D60 - rain size at which 60% of the soil is finer Cc - Concavity coefficient = (D30) 2 / (D10 x D60) Cu - Uniformity coefficient = D60 / D10 Cc and Cu are used to assess the grading of sands and gravels: Well-graded gravels have: 1 < Cc < 3 and Cu > 4 Well-graded sands have: 1 < Cc < 3 and Cu > 6 Sands and gravels not meeting the above requirements are poorly-graded or uniformly-graded. Cc and Cu are not applicable for the description of soils with more than 10% silt and clay (more than 10% finer than mm or the #200 sieve) CONSOLIDATION TEST p o - Present effective overburden pressure at sample depth p c - Preconsolidation pressure of (maximum past pressure on) sample Ccr - Recompression index (in effect at pressures below p c ) Cc - Compression index (in effect at pressures above p c ) OC Ratio Overconsolidaton ratio = p c / p o Void Ratio Initial sample void ratio = volume of voids / volume of solids Wo - Initial water content (at start of consolidation test) PERMEABILITY TEST k - Coefficient of permeability or hydraulic conductivity is a measure of the ability of water to flow through the sample. The value of k is measured at a specified unit weight for (remoulded) cohesionless soil samples, because its value will vary with the unit weight or density of the sample during the test.

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18 SITE Source: oogle Maps FIURE 1 KEY PLAN

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