patersongroup 1.0 Field Observations Consulting Engineers November 25, 2015 File: PG3677-LET.01 Habitat for Humanity 768 Belfast Road Ottawa, Ontario

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1 November 5, 5 File: P677-LET. Habitat for Humanity 768 Belfast Road K Z5 5 Colonnade Road South KE 7J5 Tel: (6) 6-78 Fax: (6) 6-6 eotechnical Engineering Environmental Engineering Hydrogeology eological Engineering Materials Testing Building Science Archaeological Services Attention: Ms. Alexis Ashworth Subject: eotechnical Investigation Proposed Residential Development 68 Jeanne D Arc Boulevard North - Ottawa Dear Ms. Ashworth, Paterson roup (Paterson) carried out a geotechnical investigation for the proposed residential development to be located at the aforementioned site. It is understood that the proposed development will consist of townhouses with two storey residential structures with a full basement level. The following report presents our findings and recommendations.. Field Observations Surface Conditions The subject site is a vacant property with no buildings present located on the southeast corner of the intersection between Jeanne D Arc Boulevard and Fortune Drive. The ground surface across the subject site is relatively flat, at grade with neighbouring properties and slightly above grade with both Jeanne D Arc Boulevard and Fortune Drive. The property is located in a residential neighbourhood, with an elementary school located north of the site across Fortune Drive. Subsoil Conditions Based on readily available historical information, it is understood that subsurface conditions at the subject site consist of a layer of fill consisting of a mixture of sand and gravel extending to depths ranging from. to m below existing grade. The fill is underlain by a stiff to very stiff grey silty clay deposit. Ottawa Kingston North Bay

2 Ms. Alexis Ashworth Page File: P677-LET. Based on available geological mapping, the bedrock in the area consists of dolomite of the Lower Ordovician Oxford formation. The overburden drift thickness ranges from 5 to 5 m in depth. roundwater Historical groundwater levels in the area indicate the long term water table exists at approximately m below existing grade. It is expected that a perched groundwater condition may exist within the fill material. roundwater levels were measures on August 6, 5 in BH, BH and BH 6 and ranged from. to m below existing grade.. eotechnical Assessment The subject site was a former fuel dispensing site that was subjected to a decommissioning of the fuel handling equipment and environmentally impacted soil. During this decommissioning program the site was backfilled with clean backfill. However, the compaction effort was limited and may require engineered fill as the replacement material below foundations. From a geotechnical perspective, the subject site is satisfactory for the proposed development. It is expected that the proposed structures will be founded on conventional shallow spread footings placed on a stiff silty clay bearing surface and/or engineered fill. Site Preparation and Fill Placement 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, unless otherwise specified, should consist of clean imported granular fill, such as Ontario Provincial Standard Specifications (OP) ranular A or ranular 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 mm thick and compacted using suitable compaction equipment for the lift thickness. Fill placed beneath the building should be compacted to at least 98 of its standard Proctor maximum dry density (SPMDD). 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. patersongroup

3 Ms. Alexis Ashworth Page File: P677-LET. Foundation Design Footings placed on an undisturbed, stiff silty clay bearing surface or engineered fill over a stiff silty clay bearing surface can be designed using a bearing resistance value at serviceability limit states (SLS) of 5 kpa and a factored bearing resistance value at ultimate limit states (ULS) of 5 kpa. A geotechnical resistance factor of.5 was applied to the bearing resistance values at ULS. An undisturbed soil bearing surface consists of a surface from which all topsoil and fill containing 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 resistance values at SLS will be subjected to potential post-construction total and differential settlements of 5 and 5 mm, respectively. Design for Earthquakes Based on the existing soils information, the site class for seismic site response can be taken as Class D for the foundations considered at this site. The soils underlying the proposed shallow foundations are not susceptible to liquefaction. Reference should be made to the latest revision of the 6 Ontario Building Code for a full discussion of the earthquake design requirements. Basement Slab With the removal of topsoil and deleterious fill containing organic material within the footprint of the proposed building, the native silty clay or existing fill, free of organics and deleterious materials, and approved by the geotechnical consultant at the time of construction will be considered an acceptable subgrade on which to commence backfilling for floor slab construction. Any soft areas should be removed and backfilled with appropriate backfill material prior to placing any fill. OP ranular B Type I or II, with a maximum particle size of 5 mm, are recommended for backfilling below the floor slab. It is recommended that the upper mm of sub-floor fill consists of a 9 mm clear crushed stone. All backfill material within the footprint of the proposed building should be placed in maximum mm thick loose layers and compacted to at least 98 of its SPMDD. patersongroup

4 Ms. Alexis Ashworth Page File: P677-LET.. Design and Precautions Foundation Drainage A perimeter foundation drainage system is recommended for the proposed building. It should consist of a mm diameter perforated corrugated plastic pipe, surrounded on all sides by 5 mm of 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 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 used in conjunction with a drainage geocomposite, such as Miradrain N or Delta Drain 6, connected to the perimeter foundation drainage system. Imported granular materials, such as clean sand or OP ranular B Type I granular material, should otherwise be used for this purpose. Protection of Footings Against Frost Action Perimeter footings of heated structures are required to be insulated against the deleterious effect of frost action. A minimum of.5 m thick soil cover (or combination of soil cover and 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. 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). patersongroup

5 Ms. Alexis Ashworth Page 5 File: P677-LET. The excavation side slopes above the groundwater level extending to a maximum depth of m should be cut back at H:V or flatter. The flatter slope is required for excavation below groundwater level. The subsoil at this site is considered to be mainly Type and soil according to the Occupational Health and Safety Act and Regulations for Projects. 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 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. Pipe Bedding and Backfill The pipe bedding for sewer and water pipes should consist of at least 5 mm of OP ranular A material. The material should be placed in maximum mm thick lifts and compacted to a minimum of 95 of its SPMDD. The bedding material should extend at least to the spring line of the pipe. The cover material, which should consist of OP ranular A, should extend from the spring line of the pipe to at least mm above the obvert of the pipe. The material should be placed in maximum mm thick lifts and compacted to a minimum of 95 of its SPMDD. It should generally be possible to re-use the native silty clay above the cover material if the excavation and filling operations are carried out in dry weather conditions. Where hard surface areas are considered above the trench backfill, the trench backfill material within the frost zone (about.8 m below finished grade) should match the soils exposed at the trench walls to minimize differential frost heaving. The trench backfill should be placed in maximum mm thick loose lifts and compacted to a minimum of 95 of the material s SPMDD. roundwater 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. It is expected that groundwater flow into the excavation through the sides of the excavation will be controllable using open sumps and pumps. patersongroup

6 Ms. Alexis Ashworth Page 6 File: P677-LET. Corrosion Potential and Sulphate The results of historical analytical testing show that the sulphate content is less than.. This result is indicative that Type Portland cement (normal cement) would be appropriate for this site. The results of testing also indicate that ph is not a significant factor in creating a corrosive environment for exposed ferrous metals at this site.. 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. 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. Upon demand, 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. 5. 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 Habitat for Humanity or their agents is not authorized without review by this firm for the applicability of our recommendations to the altered use of the report. patersongroup

7 Ms. Alexis Ashworth Page 7 File: P677-LET. We trust that this report satisfies your requirements. Best Regards, Paterson roup Inc. Carlos P. Da Silva, P.Eng. Attachments Soil Profile and Test Data Sheets Symbols and Terms Figure - Key Plan Drawing PE6- - Test Hole Location Plan patersongroup

8 5 Colonnade Road South, KE 7J5 BORINS BY 68 Jeanne D'Arc Boulevard TBM - Nut on lower portion of fire hydrant. Assumed elevation =.m. eoprobe August, 5 PE6 BH ROUND SURFACE 99.6 Lower Explosive Limit FILL: Mixture of sand and gravel, trace silty clay and asphalt End of Borehole.6 5 Full as Resp. Methane Elim.

9 5 Colonnade Road South, KE 7J5 BORINS BY eoprobe 68 Jeanne D'Arc Boulevard TBM - Nut on lower portion of fire hydrant. Assumed elevation =.m. August, 5 PE6 BH ROUND SURFACE 99.7 Lower Explosive Limit 6 8 FILL: Silty sand with gravel A 86 B C 9 FILL: Crushed stone, trace silty clay and sand Very stiff to stiff, grey SILTY CLAY End of Borehole Full as Resp. Methane Elim.

10 5 Colonnade Road South, KE 7J5 BORINS BY eoprobe 68 Jeanne D'Arc Boulevard TBM - Nut on lower portion of fire hydrant. Assumed elevation =.m. August, 5 PE6 BH ROUND SURFACE. Lower Explosive Limit FILL: Brown to grey sand rey SANDY CLAY.96.7 A B 96. rey SILTY CLAY C End of Borehole.88 6, 5) 5 Full as Resp. Methane Elim.

11 5 Colonnade Road South, KE 7J5 BORINS BY 68 Jeanne D'Arc Boulevard TBM - Nut on lower portion of fire hydrant. Assumed elevation =.m. eoprobe August, 5 PE6 BH ROUND SURFACE Lower Explosive Limit 6 8 FILL: Brown silty sand, some gravel, trace clay, asphalt, topsoil Very stiff to firm, grey-brown SILTY CLAY grey by.m depth End of Borehole.88 5 Full as Resp. Methane Elim.

12 5 Colonnade Road South, KE 7J5 BORINS BY 68 Jeanne D'Arc Boulevard TBM - Nut on lower portion of fire hydrant. Assumed elevation =.m. eoprobe August, 5 PE6 BH 5 ROUND SURFACE 99.7 Lower Explosive Limit 6 8 FILL: Crushed stone and sand 5. A 98.7 B rey-brown SILTY CLAY - grey by.m depth C End of Borehole.88 6, 5) 5 Full as Resp. Methane Elim.

13 5 Colonnade Road South, KE 7J5 BORINS BY eoprobe 68 Jeanne D'Arc Boulevard TBM - Nut on lower portion of fire hydrant. Assumed elevation =.m. August, 5 PE6 BH 6 ROUND SURFACE Lower Explosive Limit FILL: Crushed stone with sand, trace silt and clay A rey SILTY CLAY B End of Borehole.88 6, 5) 5 Full as Resp. Methane Elim.

14 5 Colonnade Road South, KE 7J5 BORINS BY 68 Jeanne D'Arc Boulevard TBM - Nut on lower portion of fire hydrant. Assumed elevation =.m. eoprobe August, 5 PE6 BH 7 ROUND SURFACE 99.6 Lower Explosive Limit FILL: Crushed stone with sand, trace silt and clay FILL: Sand with clay rey-brown SILTY CLAY grey by.7m depth 95.6 End of Borehole.88 5 Full as Resp. Methane Elim.

15 5 Colonnade Road South, KE 7J5 BORINS BY Backhoe 68 Jeanne D'Arc Boulevard September, 5 PE6 TP ROUND SURFACE FILL: Silty snd, some clay. Lower Explosive Limit 6 8 FILL: Crushed stone End of Test Pit. 5 Full as Resp. Methane Elim.

16 5 Colonnade Road South, KE 7J5 BORINS BY Backhoe 68 Jeanne D'Arc Boulevard September, 5 PE6 TP ROUND SURFACE Lower Explosive Limit 6 8 FILL: Brown silty sand, some clay rey-brown SILTY CLAY End of Test Pit..5 5 Full as Resp. Methane Elim.

17 5 Colonnade Road South, KE 7J5 BORINS BY Backhoe 68 Jeanne D'Arc Boulevard September, 5 PE6 TP ROUND SURFACE Asphaltic concrete FILL: Crushed stone FILL: Brown silty sand TOPSOIL Lower Explosive Limit 6 8 Brown SILTY CLAY grey by.5m depth 6 7 End of Test Pit Full as Resp. Methane Elim.

18 5 Colonnade Road South, KE 7J5 Backhoe 68 Jeanne D'Arc Boulevard September, 5 PE6 BORINS BY TP ROUND SURFACE Asphaltic concrete FILL: Crushed stone FILL: Brown silty sand, trace clay.8.8 Lower Explosive Limit 6 8 TOPSOIL.. Brown CLAYEY SAND, some gravel and silt.8 rey-brown SILTY CLAY - grey by.m depth End of Test Pit. 5 5 Full as Resp. Methane Elim.

19 5 Colonnade Road South, KE 7J5 BORINS BY Backhoe 68 Jeanne D'Arc Boulevard September, 5 PE6 TP 5 ROUND SURFACE FILL: Crushed stone, some sand. FILL: Brown silty sand.9 Lower Explosive Limit 6 8 Brown SILTY CLAY, trace topsoil - grey-brown by.m depth End of Borehole. 5 5 Full as Resp. Methane Elim.

20 5 Colonnade Road South, KE 7J5 BORINS BY Backhoe 68 Jeanne D'Arc Boulevard September, 5 PE6 TP 6 ROUND SURFACE Lower Explosive Limit 6 8 FILL: Brown silty sand, some crushed stone.8 FILL: Crushed stone FILL: rey-brown silty clay with sand..5 5 rey-brown SILTY CLAY 6 - grey by.8m depth 7 End of Test Pit.8 5 Full as Resp. Methane Elim.

21 5 Colonnade Road South, KE 7J5 BORINS BY Backhoe 68 Jeanne D'Arc Boulevard September, 5 PE6 TP 7 ROUND SURFACE FILL: Brown silty sand, trace crushed stone.5 Lower Explosive Limit 6 8 FILL: Crushed stone rey-brown SILTY CLAY End of Test Pit.. 5 Full as Resp. Methane Elim.

22 5 Colonnade Road South, KE 7J5 BORINS BY Backhoe 68 Jeanne D'Arc Boulevard September, 5 PE6 TP 8 ROUND SURFACE TOPSOIL. Lower Explosive Limit 6 8 FILL: Brown silty clay, some crushed stone.5 rey-brown SILTY CLAY - grey by.m depth End of Test Pit. 5 5 Full as Resp. Methane Elim.

23 SYMBOLS AND TERMS 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 6.5 kg hammer, falling 76 mm, required to drive a 5 mm O.D. split spoon sampler mm into the soil after an initial penetration of 5 mm. Relative Density N Value Relative Density Very Loose < <5 Loose Compact Dense Very Dense >5 >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 < < Soft -5 - Firm Stiff Very Stiff Hard > >

24 SYMBOLS AND TERMS (continued) (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 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 9- Excellent, intact, very sound 75-9 ood, massive, moderately jointed or sound 5-75 Fair, blocky and seamy, fractured 5-5 Poor, shattered and very seamy or blocky, severely fractured -5 Very poor, crushed, very severely fractured S - 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.

25 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.75 mm grain size D - rain size at which of the soil is finer (effective grain size) D6 - rain size at which 6 of the soil is finer Cc - Concavity coefficient = (D) / (D x D6) Cu - Uniformity coefficient = D6 / D Cc and Cu are used to assess the grading of sands and gravels: Well-graded gravels have: < Cc < and Cu > Well-graded sands have: < Cc < 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 silt and clay (more than finer than.75 mm or the # 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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27 SITE FIURE KEY PLAN patersongroup

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