PRELIMINARY GEOTECHNICAL INVESTIGATION PROPOSED DEVELOPMENT 1520 NOTION ROAD PICKERING, ONTARIO. Prepared for: DILLON CONSULTING LIMITED.

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1 PRELIMINARY GEOTECHNICAL INVESTIGATION PROPOSED DEVELOPMENT 0 NOTION ROAD PICKERING, ONTARIO Prepared for: DILLON CONSULTING LIMITED Prepared By: SIRATI & PARTNERS CONSULTANTS LIMITED Project: SP Millway Avenue, Unit 8 August, 0 Vaughan, Ontario, L4K T Tel: Fax:

2 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario TABLE OF CONTENTS. INTRODUCTION. FIELD AND LABORATORY WORK. SITE AND SUBSURFACE CONDITIONS. SOIL CONDITIONS:.... GROUNDWATER CONDITIONS SITE GRADING AND GROUND IMPROVEMENT 4. SUBGRADE PREPARATION GRANULAR BLANKET AND HORIZONTAL DRAINAGE WICK DRAINS ENGINEERED FILL TO RAISE THE GRADE SURCHARGE LOAD FILL GEOTECHNICAL MONITORING AND INSTRUMENTATION FOUNDATIONS 8. FOOTINGS FOUNDED ON IMPROVED GROUND DRILLED CAIONS OTHER COMMENTS ON FOUNDATIONS FLOOR SLAB 9. EARTH PREURE 0 8. EXCAVATION AND BACKFILL 0 9. EARTHQUAKE CONSIDERATIONS 0. GENERAL COMMENTS ON REPORT DRAWINGS/ENCLOSURES BOREHOLE LOCATION PLAN NOTES ON SAMPLE DESCRIPTIONS BOREHOLE LOGS GRADATION CURVES DRAINAGE & BACKFILL RECOMMENDATIONS NO. A SIRATI & PARTNERS CONSULTANTS LIMITED i AUGUST, 0

3 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario APPENDIX A: GUIDELINES FOR ENGINEERED FILL APPENDIX B: GENERAL COMMENTS ON SHALE BEDROCK APPENDIX C: LIMITATIONS OF REPORT SIRATI & PARTNERS CONSULTANTS LIMITED ii AUGUST, 0

4 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario. INTRODUCTION Sirati & Partners Consultants Limited (SPCL) was retained by to undertake a geotechnical investigation for the proposed development located at 0 Notion Road, Pickering, Ontario. Based on the information provided by the client, the project will consist of construction of residential houses along the Marshcourt Drive (on the west side of the Property) and low-rise commercial development behind the proposed houses, on the remaining portion of the site. The purpose of this investigation was to determine the subsurface conditions at eight borehole locations and from the findings in the borehole make engineering recommendations for the following:. Site Grading and Ground Improvement. Foundations. Floor slab and permanent drainage 4. Excavations and backfill. Earthquake considerations. Earth Pressures This geotechnical report should be considered preliminary in nature and should be updated when the design details of the proposed development are finalized. This report is provided on the basis of the terms of reference presented above and on the assumption that the design will be in accordance with the applicable codes and standards. If there are any changes in the design features relevant to the geotechnical analyses, or if any questions arise concerning the geotechnical aspects of the codes and standards, this office should be contacted to review the design. It may then be necessary to carry out additional borings and reporting before the recommendations of this office can be relied upon. The recommendations follow generally accepted practice for geotechnical consultants in Ontario. The format and contents are guided by client specific needs and economics and do not conform to generalized standards for services. Laboratory testing for most part follows ASTM or CSA Standards or modifications of these standards that have become standard practice. This report has been prepared for and its designers. Third party use of this report without Sirati & Partners Consultants Limited (SPCL) consent is prohibited. The limitation conditions presented in Appendix C form an integral part of the report and they must be considered in conjunction with this report. SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

5 Project: SP FIELD AND LABORATORY WORK Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario Eight boreholes (BH to BH8, see Drawing for location plan) were drilled at site to depths ranging from 8. to 4.m. Boreholes were drilled using solid and hollow stem continuous flight augers equipment by a drilling sub-contractor under the direction and supervision of SPCL personnel. Continuous samples were retrieved with a 0 mm O.D. split-barrel sampler driven with a hammer weighing 4 N and dropping 0 mm in accordance with the Standard Penetration Test (SPT) method. The samples were logged in the field and returned to the SPCL laboratory for detailed examination by the project engineer and for laboratory testing. As well as visual examination in the laboratory, all of the soil samples were tested for moisture content. Selected six soil samples were subjected to grain size analyses and results are presented on Drawing 0 of this report. Selected four soil samples were subjected to consistency (Atterberg Limits) testing and the results are presented on the respective borehole logs. Vane shear tests were conducted in the weak silty clay/silty clay till to measure the in-situ undrained shear strengths of the soils. Water level observations were made during drilling and in the open boreholes at the completion of the drilling operations. Monitoring wells were installed at three () borehole locations (BH, BH & BH8) for the long-term (stabilized) groundwater level monitoring. The elevations at the borehole locations were surveyed by SPCL using a differential GPS unit and are provided on the respective borehole logs.. SITE AND SUBSURFACE CONDITIONS The subject site is located on the north-west corner of Notion Road and Pickering Parkway in Pickering, Ontario. The site is bounded by Marshcourt Drive on the west side and existing houses on Marshcourt Drive on the north side. Currently, the property is vacant of any structures and is generally covered with grass, trees and bushes. Topography of the site is generally flat, with some undulating areas. The borehole location plan is shown on Drawing. Notes on soil descriptions are presented on Drawing A. The subsurface conditions in the boreholes are presented in the borehole logs (Encl. to 9). The subsurface conditions in the borehole are summarized in the following paragraphs.. SOIL CONDITIONS: Topsoil/Fill Material: A surficial topsoil layer, ranging in thickness from 0 to 80mm, was encountered at the borehole locations. Fill material was encountered in the boreholes, extending to depths ranging from 0.8 to SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

6 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario.m. Fill material generally consisted of very loose to loose/firm sandy silt to clayey silt, with measured SPT N values ranging from to 0 blows per 00mm penetration. Upper Clayey Silt Crust: Below the fill material, upper native soil consisting of clayey silt was encountered, extending to depths varying from. to.m below the existing grade. The clayey silt deposit was present in a stiff to very stiff consistency, with measured SPT N values ranging from to blows per 00mm penetration. Grain size analysis of one clayey silt sample (BH/) was conducted and the results are presented on Figure 0, with the following fractions: Clay: % Silt: 8% Sand: % Atterberg Limits testing was carried out on one clayey silt sample (BH/) and results are presented on borehole log, with the following limits: Middle Weak Silty Clay / Silty Clay Till Liquid Limit: 9% Plastic Limit: 9% Plasticity Index: 0 Below the upper clayey silt crust, very soft to firm silty clay and silty clay till deposits were encountered, extending to depths varying from 4.9 to. m. The thickness of weak clayey deposits in boreholes varied from. to 9.m. Consistency of weak silty clay/silty clay till ranged from very soft to firm, with measured SPT N values ranging from weight of hammer (WH-nil blows) to blows per 00mm penetration. Grain size analyses of two silty clay samples (BH/8 and BH/) were conducted and the results are presented on Figure 0, with the following fractions: Clay: % Silt: 4% Sand: % Atterberg Limits testing was carried out on two silty clay samples (BH/8 and BH/) and results are presented on borehole logs, with the following limits: Liquid Limit: 0 to 4% Plastic Limit: 9 to % Plasticity Index: to SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

7 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario Grain size analysis of one silty clay till sample (BH/) was conducted and the results are presented on Figure 0, with the following fractions: Clay: % Silt: 4% Sand: % Gravel: % Atterberg Limits testing was carried out on one silty clay till sample (BH/) and results are presented on borehole log, with the following limits: Lower Sandy Silt to Silty Sand Till Liquid Limit: 9% Plastic Limit: % Plasticity Index: Sandy silt to silty sand till deposit was encountered in boreholes below the middle weak silty clay soils and extending to the maximum explored depths of the boreholes or overlying shale bedrock. Sandy silt to silty sand till was present in a compact to very dense state, with the measured SPT N values ranging from to over 0 blows per 00 mm penetration. Occasional cobble/boulder were inferred in the boreholes during drilling. Grain size analyses of two sandy silt to silty sand till samples (BH/ and BH/) were conducted and the results are presented on Figure 0, with the following fractions: Shale Bedrock Clay: 4 to 0% Silt: to 4% Sand: to 0% Gravel: % Shale bedrock was encountered at two borehole locations, BH and BH4, below depths ranging from. to.m, corresponding to Elevations 9. to 0.9m. Shale bedrock was confirmed with SPT sample in BH4 and there was auger refusal on possible bedrock in BH. The quality of shale bedrock was not proven by bedrock coring. Commonly the till overlying the shale contains slabs of limestone which would give a false indication of the bedrock level. Similarly, the depth of weathering cannot be determined accurately due to the presence of limestone layers. Methane gas is anticipated in the bedrock. Appropriate care and monitoring is essential in all confined bedrock excavations, particularly for caissons. Stress relief features such as folds and faults SIRATI & PARTNERS CONSULTANTS LIMITED 4 AUGUST, 0

8 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario are common in the shale bedrock. Appendix B presents more details and general comments about the shale bedrock.. GROUNDWATER CONDITIONS During drilling, short-term groundwater table was found at depths of. to.0m below the existing grade. The stabilized groundwater levels observed in the monitoring wells on April, 0 were at depth ranging from.9 to 4.mbgs, corresponding to Elevations 8.9 to 8.0m, as listed on Table below. BH No. Table : Groundwater Levels Observed in Boreholes/Monitoring well Date of Date of Depth of Elevation of Drilling Observation Groundwater Groundwater (m) (m) Notes Mar. 0/ During drilling BH Mar. 0/ Apr., Monitoring well BH Mar. / Mar. / during drilling BH Mar. 0/ Mar. 0/. 80. during drilling BH4 Mar. 0/ Mar. 0/ during drilling BH Mar. / Mar. /. 9.0 during drilling BH Mar. 0/ Mar. 0/ during drilling BH Mar. / Apr., Monitoring well BH8 Mar. / Apr., Monitoring well It should be noted that the groundwater levels can vary and are subject to seasonal fluctuations in response to major weather events. 4. SITE GRADING AND GROUND IMPROVEMENT Based on the information provided by the client, the project will consist of construction of residential houses along the Marshcourt Drive (on the west side of the Property) and low-rise commercial development behind the proposed houses, on the remaining portion of the site. The finished floor elevation of the proposed development will be at about Elevation 84.0m. The existing grade at site varies from Elev. 8.0 to 8.0, in that case, there will a grade raise of about to m for the proposed development. Weak/very soft to soft silty clay to silty clay till deposits were encountered in boreholes, ranging in thickness from m to 9.m. Significant settlements of weak clayey deposits will occur under increased load conditions from grade raise and from the proposed structures. Based on the preliminary settlement estimation, increased loading condition from grade raise and structures load will result in ground settlement approximately in the range of to 0 mm, mainly due to the consolidation of the weak underlying silty clay soils. SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

9 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario In order to avoid the excessive post-construction settlements under the fill load from grade raise and structures, the physical properties of the on-site soils can be improved by pre-loading. Simple surcharging without wick drains can take many years (more than years for completion of 90% of total settlement) for the settlement to occur. This is not considered practical. Soil consolidation using wick drains can rapidly increase settlement rates and reduce the project durations drastically. It is recommended that pre-loading surcharge fill and wick drains be adopted to improve the ground in order to reduce the post-construction settlements and time to complete the settlement. Ground consolidation using wick drains and surcharge load fill must be carried out prior to the installation of pavements and other proposed structures. 4. SUBGRADE PREPARATION In the areas for wick drain installation, all topsoil, existing fill and any other unsuitable materials must be removed. After the removal of existing fill and all unsuitable materials, the excavation base consisting of native soil deposits must be inspected and approved by a qualified geotechnical engineer prior to any placement of granular blanket. Prior to the placement of the granular blanket, the subgrade should be graded to have a slope of about 0.% to % toward exterior drainage ditches. Any backfill required to raise the grade for a sloped subgrade surface should consist of Granular B material compacted to 98% of SPMDD. 4. GRANULAR BLANKET AND HORIZONTAL DRAINAGE After the preparation of the subgrade, a granular blanket should then be placed as the horizontal drainage for the seepage from the vertical wick drains to be installed. The thickness of the granular blanket (Granular 'B' Type II) should be at least 00 mm. The granular blanket should be compacted to 9% ± % of SPMDD. 4. WICK DRAINS The prefabricated wick drains should consist of a continuous plastic drainage core wrapped in a nonwoven geotextile material. The wick drains must be installed to the required depth. The required tip depth and elevation of the wick drains at the borehole locations are listed on Table 4. The wick drains should be cut at the surface such that at least a 0 mm length protrudes above the top of the granular blanket at each drain location. Vertical wick drains shall be installed subsequent to the construction of the granular blanket and prior to installation of monitoring instruments and placement of the engineered fill above the granular blanket. The wick drains should be installed vertically, within a plumbness tolerance of not more than %. SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

10 Project: SP-98-0 Table. Depth of Wick Drains at Borehole Locations Borehole No. Wick Drain Tip Depth Below Existing Grade / Elevation (m) BH./.0 BH./.0 BH.0/.9 BH4./.0 BH./0. BH.4/. BH./.8 BH8.4/.4 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario It is recommended that the wick drains can be installed in a triangular pattern. The horizontal spacing (B) between adjacent wick drains will determine the duration of the surcharge loading for a certain degree of consolidation of the weak silty clay deposits under surcharge loading. The actual required duration of the surcharge loading must be determined by field monitoring of settlement and pore pressure dissipation in the weak silty clay deposits. 4.4 ENGINEERED FILL TO RAISE THE GRADE After the installation of wick drains, engineered fill can be placed above the granular blanket to raise the grade to the design elevation. The material for engineered fill should consist of approved inorganic soil, compacted to 00 percent of Standard Proctor Maximum Dry Density (SPMDD), at a placement water content within % of its optimum water content. The select inorganic material must be environmentally suitable and free from organics, debris and any other unsuitable materials. Recommendations regarding engineered fill placement are provided in Appendix A of this report. It is estimated that the settlement of the native ground below the engineered fill will be about 0. to 0. m (say 0. m on average) due to the loading of the engineered fill to raise the grade and due to the surcharge load fill. The pre-grade elevation must be set to compensate for the settlement of the grade due to consolidation as well as the settlement of engineered fill. After removal of the surcharge load fill, if the top of the engineered fill is above Elev. 84. m, the extra engineered fill can be removed. If the top of the engineered fill is below Elev. 84. m, the grade can be raised to Elev. 84. m using engineered fill consisting of select inorganic material compacted to 00% of SPMDD. SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

11 Project: SP SURCHARGE LOAD FILL Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario After the placement of the engineered fill to the anticipated elevation, surcharge load fill can be placed to consolidate the ground. Assuming the additional load from the proposed structures to be about kpa, the required thickness of the surcharge load fill will be 4.0 m above Elev.84. m. All other details about the surcharge load can be finalized when the design details such as the final grading plans and loadings from the proposed structures are available. 4. GEOTECHNICAL MONITORING AND INSTRUMENTATION For the ground consolidation using wick drains and surcharge load fill, the vertical settlement and horizontal movement of the ground, and the pore pressure dissipation in the weak silty clay deposits must be monitored. The monitoring data of settlement and pore pressure in soils will be used to determine the required duration of the surcharge load fill. The monitoring equipment details will be provided at the detail design stage.. FOUNDATIONS Based on the information provided to us by the client, the project will consist of construction of normal single family houses close to the Marshcourt Drive and commercial building behind the proposed houses, facing Notion Road. The finished floor of the proposed buildings will be at about Elevation 84.0m. Soil conditions encountered in the boreholes are not suitable to support the proposed development on conventional footings without the pre-consolidation/improvement of the ground with surcharging and wick drains. Otherwise, deep foundations such as drilled caissons are required to support the proposed development.. FOOTINGS FOUNDED ON PRE-CONSOLIDATED GROUND After the consolidation of the underlying weak soils, both engineered fill and underlying native soils are considered suited to support the footings of the houses. Footings can be designed for bearing capacity values of 00 kpa at SLS and 0 kpa at ULS. The engineered fill supporting footings should be constructed in accordance with the guidelines presented in Appendix A.. DRILLED CAIONS Alternatively, the proposed structures can be supported by drilled caissons founded in the shale bedrock. Drilled caissons founded in sound shale bedrock at about. m below the bedrock surface can be designed for a bearing capacity of 000 kpa at SLS (serviceability limit states), and for a factored geotechnical resistance of 00 kpa at ULS (ultimate limit states). SIRATI & PARTNERS CONSULTANTS LIMITED 8 AUGUST, 0

12 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario As described in Section., shale bedrock in BH and BH4 was found below depths ranging from. to.m, corresponding to Elevations 9. to 0.9m. However, the quality of shale was not confirmed by bedrock coring. Additional deep boreholes will be required to confirm the depths and quality of bedrock at site at the final design stage. The presence of groundwater table in the middle cohesionless deposits will make the construction of the caissons difficult. An oversize liner will be required and must be sealed in shale bedrock, in order to prevent seepage and caving of the wet sand layers in the caisson holes. Caisson bases must be confirmed to be dry and clean prior to the pouring of concrete.. OTHER COMMENTS ON FOUNDATIONS The foundations designed to the specified allowable bearing capacity at the serviceability limit states (SLS) are expected to settle less than mm total and 9 mm differential. All footings exposed to seasonal freezing conditions must have at least.m of soil cover for frost protection. Prior to placing concrete, all foundation bases must be inspected by this office to confirm the founding levels, founding soil/bedrock conditions and design bearing values. Where it is necessary to place footings at different levels, the upper footing must be founded below an imaginary 0 horizontal to vertical line drawn up from the base of the lower footing. The lower footing must be installed first to help minimize the risk of undermining the upper footing. For caissons in bedrock, the upper foundation must be founded below an imaginary horizontal to vertical (H:V) line drawn up from the base of the lower foundation. The lower foundation must be installed first to help minimize the risk of undermining the upper foundation. It should be noted that the recommended bearing capacities have been calculated by SPCL from the borehole information for the design stage only. The investigation and comments are necessarily ongoing as new information of the underground conditions becomes available. For example, more specific information is available with respect to conditions between boreholes when foundation construction is underway. The interpretation between boreholes and the recommendations of this report must therefore be checked through field inspections provided by SPCL to validate the information for use during the construction stage.. FLOOR SLAB The floor slab can be supported on grade provided all topsoil, fill, and surficially softened soils are removed and the base thoroughly proof rolled. The fill required to raise the grade can consist of inorganic soil, placed in shallow lifts and compacted to 98 percent of Standard Proctor Maximum Dry Density (SPMDD). SIRATI & PARTNERS CONSULTANTS LIMITED 9 AUGUST, 0

13 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario A moisture barrier consisting of at least 00 mm of 9 mm clear crushed stone should be installed under the floor slab. A perimeter and underfloor drainage system will be required for structures with basement. Typical drainage and backfill recommendations are illustrated on Drawing for the structures with basement. For the structures without basement, if the floor slab is more than about 00 mm higher than the exterior grade, then perimeter drainage is not considered to be necessary. If the floor is lower, then the perimeter drainage system shown on Drawing is recommended.. EARTH PREURE The lateral earth pressures acting on basement walls or retaining walls may be calculated from the following expression: p = K( h +q) where p = Lateral earth pressure in kpa acting at depth h K = Earth pressure coefficient equal to 0.40 for vertical walls and horizontal backfill used for permanent construction. Water pressure must be considered, if continuous wall drains are not used. = Unit weight of backfill, a value of 0. kn/m may be assumed h = Depth to point of interest in metres q = Equivalent value of surcharge on the ground surface in kpa The above expression assumes that the perimeter drainage system prevents the build-up of any hydrostatic pressure behind the wall. 8. EXCAVATION AND BACKFILL Excavations can be carried out with heavy hydraulic backhoe. No major problems with groundwater are anticipated for excavation to a depth of about m. It is expected that any seepage, which occurs during wet periods, can be removed by pumping from sumps. It should be noted that the till is a non-sorted sediment and therefore may contain boulders. Possible large obstructions such as buried concrete pieces are also anticipated in the fill material. Provisions must be made in the excavation contract for the removal of possible boulders in the till or obstructions in the fill material. SIRATI & PARTNERS CONSULTANTS LIMITED 0 AUGUST, 0

14 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario All excavations must be carried out in accordance with the most recent Occupational Health and Safety Act (OHSA). In accordance with OHSA, the overburden soil can be classified as Type soil above groundwater table and Type 4 below groundwater table. The select inorganic fill and upper clayey silt free from topsoil and organics can be used as general construction backfill where it can be compacted with sheep's foot type compactors. Loose lifts of soil, which are to be compacted, should not exceed 00 mm. Silty clay soils excavated from below the groundwater table will be too wet to reuse and will require significant aeration prior to its use. The excavated soils are not considered to be free draining. Where free draining backfill is required, imported granular fill such as OP Granular B should be used. Underfloor fill should be compacted to at least 98 percent of Standard Proctor Maximum Dry Density (SPMDD). It should be noted that the excavated soils are subject to moisture content increase during wet weather which would make these materials too wet for adequate compaction. Stockpiles should be compacted at the surface or be covered with tarpaulins to minimize moisture uptake. 9. EARTHQUAKE CONSIDERATIONS Based on the borehole information and according to Table A of OBC 0, the subject site for the proposed buildings can be classified as Class D for seismic site response. 0. GENERAL COMMENTS ON REPORT Sirati & Partners Consultants Limited (SPCL) should be retained for a general review of the final design and specifications to verify that this report has been properly interpreted and implemented. If not accorded the privilege of making this review, Sirati & Partners will assume no responsibility for interpretation of the recommendations in the report. The comments given in this report are intended only for the guidance of design engineers. The number of boreholes required to determine the localized underground conditions between boreholes affecting construction costs, techniques, sequencing, equipment, scheduling, etc., would be much greater than has been carried out for design purposes. Contractors bidding on or undertaking the works should, in this light, decide on their own investigations, as well as their own interpretations of the factual borehole results, so that they may draw their own conclusions as to how the subsurface conditions may affect them. The limitation conditions presented in Appendix C form an integral part of the report and they must be considered in conjunction with this report. SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

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16 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario Drawings SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

17 N o t i o n R o a d Pickering Parkway. NOTES:. The boundaries and soil types have been established only at borehole locations. Between and beyond boreholes they are assumed and may be subject to considerable error.. Soil samples will be retained in storage for months and then destroyed unless the client advises an extended time period is required.. Topsoil / granular quantities should not be established from the information provided at the borehole locations. 4. Borehole elevations should not be used to design building(s) or floor slab(s) or parking lot(s) grades.. This drawing forms part of the report (project number as referenced) and should only be used in conjunction with Client: Date: 8-Apr- Scale: N.T.S Original Size: Drawn: LG Approved: AS Tabloid Rev: N/A Project No SP-98-0 Drawing No: Title: Borehole Location Plan Project: Geotechnical Investigation-0 Notion Road, Pickering, ON

18 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario Drawing A: Notes on Sample Descriptions. All sample descriptions included in this report follow the Canadian Foundations Engineering Manual soil classification system. This system follows the standard proposed by the International Society for Soil Mechanics and Foundation Engineering. Laboratory grain size analyses provided by Sirati & Partners Consultants Limited also follow the same system. Different classification systems may be used by others; one such system is the Unified Soil Classification. Please note that, with the exception of those samples where a grain size analysis has been made, all samples are classified visually. Visual classification is not sufficiently accurate to provide exact grain sizing or precise differentiation between size classification systems. IMFE SOIL CLAIFICATION CLAY SILT SAND GRAVEL COBBLES BOULDERS FINE MEDIUM COARSE FINE MEDIUM COARSE FINE MEDIUM COARSE EQUIVALENT GRAIN DIAMETER IN MILLIMETRES CLAY (PLASTIC) TO FINE MEDIUM CRS. FINE COARSE SILT (NONPLASTIC) SAND GRAVEL UNIFIED SOIL CLAIFICATION. Fill: Where fill is designated on the borehole log it is defined as indicated by the sample recovered during the boring process. The reader is cautioned that fills are heterogeneous in nature and variable in density or degree of compaction. The borehole description may therefore not be applicable as a general description of site fill materials. All fills should be expected to contain obstruction such as wood, large concrete pieces or subsurface basements, floors, tanks, etc., none of these may have been encountered in the boreholes. Since boreholes cannot accurately define the contents of the fill, test pits are recommended to provide supplementary information. Despite the use of test pits, the heterogeneous nature of fill will leave some ambiguity as to the exact composition of the fill. Most fills contain pockets, seams, or layers of organically contaminated soil. This organic material can result in the generation of methane gas and/or significant ongoing and future settlements. Fill at this site may have been monitored for the presence of methane gas and, if so, the results are given on the borehole logs. The monitoring process does not indicate the volume of gas that can be potentially generated nor does it pinpoint the source of the gas. These readings are to advise of the presence of gas only, and a detailed study is recommended for sites where any explosive gas/methane is detected. Some fill material may be contaminated by toxic/hazardous waste that renders it unacceptable for deposition in any but designated land fill sites; unless specifically stated the fill on this site has not been tested for contaminants that may be considered toxic or hazardous. This testing and a potential hazard study can be undertaken if requested. In most residential/commercial areas undergoing reconstruction, buried oil tanks are common and are generally not detected in a conventional geotechnical site investigation.. Till: The term till on the borehole logs indicates that the material originates from a geological process associated with glaciation. Because of this geological process the till must be considered heterogeneous in composition and as such may contain pockets and/or seams of material such as sand, gravel, silt or clay. Till often contains cobbles (0 to 00 mm) or boulders (over 00 mm). Contractors may therefore encounter cobbles and boulders during excavation, even if they are not indicated by the borings. It should be appreciated that normal sampling equipment cannot differentiate the size or type of any obstruction. Because of the horizontal and vertical variability of till, the sample description may be applicable to a very limited zone; caution is therefore essential when dealing with sensitive excavations or dewatering programs in till materials. SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

19 LOG OF BOREHOLE BH OF ELEV DEPTH PROJECT: Phase One & Phase Two ESAs and Geotechnical Investigation CLIENT: PROJECT LOCATION: 0 Notion Road Pickering DATUM: Geodetic BH LOCATION: See Drawing (m) SOIL PROFILE DESCRIPTION TOPSOIL: 80mm FILL: clayey silt, trace sand, trace rootlets, dark brown, moist, firm SILTY SAND: trace clay, trace gravel, brown, moist, compact CLAYEY SILT: trace sand, greyish brown, moist, stiff STRATA PLOT NUMBER SAMPLES TYPE "N" BLOWS 0. m GROUND WATER CONDITIONS ELEVATION 8 8 DRILLING DATA Method: Hollow Stem Augers Diameter: 00mm Date: Mar/0/0 DYNAMIC CONE PENETRATION RESISTANCE PLOT SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE PLASTIC LIMIT w P NATURAL MOISTURE CONTENT w LIQUID LIMIT w L WATER CONTENT (%) REF. NO.: SP-98-0 ENCL NO.: POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (kn/m ) REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI 0 CL SILTY CLAY: sandy, trace gravel, grey, wet, soft SILTY CLAY TILL: sandy, trace gravel, grey, wet, very soft WH 9 W. L. 8.9 m Apr, SANDY SILT TILL: some clay to clayey, trace gravel, grey, moist, compact to very dense SPCL SOIL LOG SP NOTION RD, PICKERING.GPJ SPCL.GDT 4/8/ END OF BOREHOLE Notes: ) Monitoring well installed in the borehole upon completion ) WH- Weight of Hammer ) Water level in monitoring well at 4.m on Mar, / 0mm GROUNDWATER ELEVATIONS st nd rd 4th Measurement GRAPH NOTES, : Numbers refer to Sensitivity =% Strain at Failure

20 LOG OF BOREHOLE BH OF ELEV DEPTH PROJECT: Phase One & Phase Two ESAs and Geotechnical Investigation CLIENT: PROJECT LOCATION: 0 Notion Road Pickering DATUM: Geodetic BH LOCATION: See Drawing (m) SOIL PROFILE DESCRIPTION TOPSOIL: 00mm FILL: clayey silt, trace sand, dark brown, moist, firm CLAYEY SILT: trace sand, greyish brown to grey, moist, stiff to very stiff STRATA PLOT NUMBER SAMPLES TYPE "N" BLOWS 0. m GROUND WATER CONDITIONS ELEVATION 8 8 DRILLING DATA Method: Hollow Stem Augers Diameter: 00mm Date: Mar//0 DYNAMIC CONE PENETRATION RESISTANCE PLOT SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE PLASTIC LIMIT w P NATURAL MOISTURE CONTENT w LIQUID LIMIT w L WATER CONTENT (%) REF. NO.: SP-98-0 ENCL NO.: POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (kn/m ) REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL SILTY CLAY: trace sand, grey, moist to wet, soft to very soft moist below 4.m 8.. SILTY CLAY TILL: sandy, trace gravel, grey, wet, very soft 8 8 WH 9 9 WH 4 SPCL SOIL LOG SP NOTION RD, PICKERING.GPJ SPCL.GDT 4/8/ firm at 0.m SANDY SILT TILL: some clay, trace gravel, grey, moist to wet, very dense auger refusal on possible shale bedrock END OF BOREHOLE Notes: ) Water level at.0m during drilling. ) WH- Weight of Hammer 0 0/ 00mm 0/ 0mm 0 9 GROUNDWATER ELEVATIONS st nd rd 4th Measurement GRAPH NOTES, : Numbers refer to Sensitivity =% Strain at Failure

21 LOG OF BOREHOLE BH OF ELEV DEPTH PROJECT: Phase One & Phase Two ESAs and Geotechnical Investigation CLIENT: PROJECT LOCATION: 0 Notion Road Pickering DATUM: Geodetic BH LOCATION: See Drawing (m) SOIL PROFILE DESCRIPTION TOPSOIL: 0mm FILL: sandy silt, trace rootlets, dark brown, moist, loose CLAYEY SILT: some sand, brown, moist, stiff STRATA PLOT NUMBER SAMPLES TYPE "N" BLOWS 0. m 9 GROUND WATER CONDITIONS ELEVATION 8 DRILLING DATA Method: Hollow Stem Augers Diameter: 00mm Date: Mar/0/0 DYNAMIC CONE PENETRATION RESISTANCE PLOT SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE PLASTIC LIMIT w P NATURAL MOISTURE CONTENT w LIQUID LIMIT w L WATER CONTENT (%) REF. NO.: SP-98-0 ENCL NO.: 4 POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (kn/m ) REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL 80.. SILTY CLAY: trace to some sand, trace gravel, grey, moist to wet, very soft to firm WH 8.. SILTY CLAY TILL: sandy, trace gravel, grey, wet, very soft 8 WH 9 4 firm at 9.m 9 SPCL SOIL LOG SP NOTION RD, PICKERING.GPJ SPCL.GDT 4/8/ SILTY SAND TILL: trace to some clay, trace gravel, grey, moist, very dense wet at.m END OF BOREHOLE Notes: ) Water level at.m during drilling. ) WH- Weight of Hammer 0 0/ 0mm 8 GROUNDWATER ELEVATIONS st nd rd 4th Measurement GRAPH NOTES, : Numbers refer to Sensitivity =% Strain at Failure

22 LOG OF BOREHOLE BH4 OF ELEV DEPTH PROJECT: Phase One & Phase Two ESAs and Geotechnical Investigation CLIENT: PROJECT LOCATION: 0 Notion Road Pickering DATUM: Geodetic BH LOCATION: See Drawing (m) SOIL PROFILE DESCRIPTION TOPSOIL: 0mm FILL: sandy silt, trace rootlets, dark brown, moist, loose CLAYEY SILT: trace sand, brown, moist, firm to stiff STRATA PLOT NUMBER SAMPLES TYPE "N" BLOWS 0. m 0 GROUND WATER CONDITIONS ELEVATION DRILLING DATA Method: Hollow & Solid Stem Augers Diameter: 00mm Date: Mar/0/ SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE DYNAMIC CONE PENETRATION RESISTANCE PLOT PLASTIC LIMIT w P NATURAL MOISTURE CONTENT w LIQUID LIMIT w L WATER CONTENT (%) REF. NO.: SP-98-0 ENCL NO.: POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (kn/m ) REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL grey below.m SILTY CLAY: trace sand, grey, moist to wet, very soft to soft VANE SILTY CLAY TILL: sandy, trace gravel, grey, wet, very soft 9 WH 4 SPCL SOIL LOG SP NOTION RD, PICKERING.GPJ SPCL.GDT 4/8/ SANDY SILT: trace clay, trace gravel, grey, wet, compact SHALE BEDROCK: weathered, grey END OF BOREHOLE Notes: ) Water level at.0m during drilling. ) WH- Weight of Hammer 0 0/ 0mm 0/ 0mm 0 9 GROUNDWATER ELEVATIONS st nd rd 4th Measurement GRAPH NOTES, : Numbers refer to Sensitivity =% Strain at Failure

23 LOG OF BOREHOLE BH OF ELEV DEPTH PROJECT: Phase One & Phase Two ESAs and Geotechnical Investigation CLIENT: PROJECT LOCATION: 0 Notion Road Pickering DATUM: Geodetic BH LOCATION: See Drawing (m) SOIL PROFILE DESCRIPTION TOPSOIL: 0mm FILL: sandy silt, trace rootlets, dark brown, moist, very loose CLAYEY SILT: trace sand, brown, moist, stiff to very stiff STRATA PLOT NUMBER SAMPLES TYPE "N" BLOWS 0. m 0 GROUND WATER CONDITIONS ELEVATION 8 DRILLING DATA Method: Hollow Stem Augers Diameter: 00mm Date: Mar//0 DYNAMIC CONE PENETRATION RESISTANCE PLOT SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE PLASTIC LIMIT w P NATURAL MOISTURE CONTENT w LIQUID LIMIT w L WATER CONTENT (%) REF. NO.: SP-98-0 ENCL NO.: POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (kn/m ) REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL 8 grey below.m SILTY CLAY: trace sand, grey, moist to wet, very soft WH 8 8 WH SPCL SOIL LOG SP NOTION RD, PICKERING.GPJ SPCL.GDT 4/8/ SILTY CLAY TILL: sandy, trace gravel, grey, wet, very soft SILTY SAND TILL: trace clay, trace gravel, trace cobble/boulder, grey, wet, dense to very dense END OF BOREHOLE Notes: ) Water level at.4m during drilling. ) WH- Weight of Hammer 9 0 WH WH 0/ 0mm 0 9 GROUNDWATER ELEVATIONS st nd rd 4th Measurement GRAPH NOTES, : Numbers refer to Sensitivity =% Strain at Failure

24 LOG OF BOREHOLE BH OF ELEV DEPTH PROJECT: Phase One & Phase Two ESAs and Geotechnical Investigation CLIENT: PROJECT LOCATION: 0 Notion Road Pickering DATUM: Geodetic BH LOCATION: See Drawing (m) SOIL PROFILE DESCRIPTION TOPSOIL: 0mm FILL: sandy silt, trace rootlets, dark brown, moist, loose CLAYEY SILT: trace sand, brown to greyish brown, moist, firm to stiff STRATA PLOT NUMBER SAMPLES TYPE "N" BLOWS 0. m 4 GROUND WATER CONDITIONS ELEVATION 8 DRILLING DATA Method: Solid Stem Augers Diameter: 0mm Date: Mar/0/0 DYNAMIC CONE PENETRATION RESISTANCE PLOT SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE PLASTIC LIMIT w P NATURAL MOISTURE CONTENT w LIQUID LIMIT w L WATER CONTENT (%) REF. NO.: SP-98-0 ENCL NO.: POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (kn/m ) REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL grey below.m SILTY CLAY: trace sand, grey, very moist to wet, very soft to soft SANDY SILT TILL: trace clay, trace gravel, grey, moist, dense SANDY SILT TO SILTY SAND TILL: trace clay, trace gravel, occasional cobble/boulder, grey, moist, very dense 8 0/ 00mm SPCL SOIL LOG SP NOTION RD, PICKERING.GPJ SPCL.GDT 4/8/ END OF BOREHOLE Notes: ) Water level at.m during drilling. 9 0/ 0mm 4 GROUNDWATER ELEVATIONS st nd rd 4th Measurement GRAPH NOTES, : Numbers refer to Sensitivity =% Strain at Failure

25 ELEV DEPTH PROJECT: Phase One & Phase Two ESAs and Geotechnical Investigation CLIENT: PROJECT LOCATION: 0 Notion Road Pickering DATUM: Geodetic BH LOCATION: See Drawing (m) SOIL PROFILE DESCRIPTION TOPSOIL: 00mm FILL: sandy silt, trace rootlets, trace organic, dark brown, moist, loose to compact CLAYEY SILT: trace sand, greyish brown to grey, moist, firm to stiff SILTY CLAY: trace sand, grey, wet, very soft STRATA PLOT NUMBER 4 SAMPLES TYPE "N" BLOWS 0. m 0 9 LOG OF BOREHOLE BH GROUND WATER CONDITIONS ELEVATION 8 W. L m Apr, 0 80 DRILLING DATA Method: Hollow Stem Augers Diameter: 00mm Date: Mar//0 DYNAMIC CONE PENETRATION RESISTANCE PLOT SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE PLASTIC LIMIT w P NATURAL MOISTURE CONTENT w LIQUID LIMIT w L WATER CONTENT (%) REF. NO.: SP-98-0 ENCL NO.: 8 POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (kn/m ) OF REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL 4 VANE SANDY SILT TO SILTY SAND TILL: some clay to clayey, trace gravel, occasional cobble/boulder, grey, moist, compact to very dense 0/ 0mm END OF BOREHOLE Notes: ) Monitoring well installed in the borehole upon completion ) Water level in monitoring well at.9m on Mar, / 0mm SPCL SOIL LOG SP NOTION RD, PICKERING.GPJ SPCL.GDT 4/8/ GROUNDWATER ELEVATIONS st nd rd 4th Measurement GRAPH NOTES, : Numbers refer to Sensitivity =% Strain at Failure

26 ELEV DEPTH PROJECT: Phase One & Phase Two ESAs and Geotechnical Investigation CLIENT: PROJECT LOCATION: 0 Notion Road Pickering DATUM: Geodetic BH LOCATION: See Drawing (m) SOIL PROFILE DESCRIPTION TOPSOIL: 0mm FILL: sandy silt, trace rootlets, dark brown, moist, loose CLAYEY SILT: trace to some sand, greyish brown, moist, stiff to very stiff SILTY CLAY: trace sand, grey, moist to wet, firm very soft below m STRATA PLOT NUMBER 4 SAMPLES TYPE "N" BLOWS 0. m LOG OF BOREHOLE BH8 WH GROUND WATER CONDITIONS ELEVATION 8 8 W. L. 80. m Apr, 0 80 DRILLING DATA Method: Hollow Stem Augers Diameter: 00mm Date: Mar//0 DYNAMIC CONE PENETRATION RESISTANCE PLOT SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE PLASTIC LIMIT w P NATURAL MOISTURE CONTENT w LIQUID LIMIT w L WATER CONTENT (%) REF. NO.: SP-98-0 ENCL NO.: 9 POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (kn/m ) OF REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL 4 VANE SANDY SILT TO SILTY SAND TILL: trace clay, trace gravel, occasional cobble/boulder, grey, moist, very dense 0/ 0mm SPCL SOIL LOG SP NOTION RD, PICKERING.GPJ SPCL.GDT 4/8/ END OF BOREHOLE Notes: ) Monitoring well installed in the borehole upon completion. ) WH- Weight of Hammer ) Water level in monitoring well at.m on Mar, 0. 8 GROUNDWATER ELEVATIONS st nd rd 4th Measurement GRAPH NOTES, : Numbers refer to Sensitivity =% Strain at Failure

27 PERCENT PAING UNIFIED SOIL CLAIFICATION SYSTEM SAND CLAY AND SILT Fine Medium Coarse GRAIN SIZE IN MICROMETERS SIEVE DESIGNATION ( Imperial ) #00 #00 #0 # #4 00 GRAVEL Fine Coarse /8" / /4 " " SP04 BH - 0 SP044 BH- 40 SP04 BH-8 0 SP04 BH- 0 SP048 BH- 0 SP04 BH GRAIN SIZE ( mm ) 0 00 GRAIN SIZE DISTRIBUTION Fig: 0 Project: SP-98-0 Date: Apr. 0

28 Project: SP-98-0 Drawing No..0 m (min.) Exterior Grade (9) Floor Slab () Impermeable Seal () Basement Wall (8) On-Site Material if Approved (4) Free Draining Backfill (4) 0 mm Clear Stone () Slab on Grade(0) Moisture Barrier () Approved Filter Membrane () 0 mm Clear Stone () Drainage Tile () EXTERIOR FOOTING Drainage Tile (, ) Approved Filter Membrane () Notes. Drainage tile to consist of 00 mm (4") diameter weeping tile or equivalent perforated pipe leading to a positive sump or outlet.. 0 mm (/4") clear stone - 0 mm (") top and side of drain. If drain is not on footing, place00 mm (4 inches) of stone below drain.. Wrap the clear stone with an approved filter membrane (Terrafix 0R or equivalent). 4. Free Draining backfill - OP Granular B or equivalent compacted to the specified density. Do not use heavy compaction equipment within 40 mm (8") of the wall. Use hand controlled light compaction equipment within.8 m (') of wall. The minimum width of the Granular 'B' backfill must be.0 m.. Impermeable backfill seal - compacted clay, clayey silt or equivalent. If original soil is free-draining, seal may be omitted. Maximum thickness of seal to be 0. m.. Do not backfill until wall is supported by basement and floor slabs or adequate bracing.. Moisture barrier to be at least 00 mm (8") of compacted clear 0 mm (/4") stone or equivalent free draining material. A vapour barrier may be required for specialty floors. 8. Basement wall to be damp proofed /water proofed. 9. Exterior grade to slope away from building. 0. Slab on grade should not be structurally connected to the wall or footing.. Underfloor drain invert to be at least 00 mm (") below underside of floor slab.. Drainage tile placed in parallel rows to 8 m (0 to ') centers one way. Place drain on 00 mm (4") clear stone with 0 mm (") of clear stone on top and sides. Enclose stone with filter fabric as noted in ().. The entire subgrade to be sealed with approved filter fabric (Terrafix 0R or equivalent) if non-cohesive (sandy) soils below ground water table encountered. 4. Do not connect the underfloor drains to perimeter drains.. Review the geotechnical report for specific details. DRAINAGE AND BACKFILL RECOMMENDATIONS Basement with Underfloor Drainage (not to scale)

29 Project: SP-98-0 Drawing No. Slab on Grade(9) Exterior Grade (8) Min.00 mm On-Site Clayey Material if Approved (4) Exterior Backfill() 0 mm Clear Stone () Approved Geotextile Filter () Capillary Break () Interior Backfill (,) Drainage Tile () EXTERIOR FOOTING Notes. Drainage tile to consist of 00 mm (4") diameter weeping tile or equivalent perforated pipe leading to a positive sump or outlet.. 0 mm (/4") clear stone - 0 mm (") top and side of drain. If drain is not on footing, place00 mm (4 inches) of stone below drain.. Wrap the clear stone with an approved geotextile filter (Terrafix 0R or equivalent). 4. The on-site clayey material, if approved, can be used as backfill in the upper 00 mm.. The interior and exterior fill adjacent to foundation walls should be OP Granular 'B' Type I. Compact to at least 98% SPMDD.. Do not use heavy compaction equipment within 40 mm (8") of the wall. Do not fill or compact within.8 m (') of the wall. Place fill on both sides simultaneously.. Capillary break to be at least 00 mm (8") of compacted clear 0 mm (/4") stone or equivalent free draining material. A vapour barrier may be required for specialty floors (consult with architect). 8. Exterior grade to slope away from building at min. %. 9. Slab on grade should not be structurally connected to the wall or footing. 0. Review the geotechnical report for specific details. DRAINAGE AND BACKFILL RECOMMENDATIONS Slab on Grade Construction Without Underfloor Drainage (not to scale)

30 Project: SP-98-0 Preliminary Geotechnical Investigation Proposed Development 0 Notion Road, Pickering, Ontario Appendix A: Guidelines for Engineered Fill SIRATI & PARTNERS CONSULTANTS LIMITED AUGUST, 0

31 Project: SP-98-0 Appendix A GENERAL REQUIREMENTS FOR ENGINEERED FILL Compacted imported soil that meets specific engineering requirements and is free of organics and debris and that has been continually monitored on a full-time basis by a qualified geotechnical representative is classified as engineered fill. Engineered fill that meets these requirements and is bearing on suitable native subsoil can be used for the support of foundations. Imported soil used as engineered fill can be removed from other portions of a site or can be brought in from other sites. In general, most of Ontario soils are too wet to achieve the 00% Standard Proctor Maximum Dry Density (SPMDD) and will require drying and careful site management if they are to be considered for engineered fill. Imported non-cohesive granular soil is preferred for all engineered fill. For engineered fill, we recommend use of OP Granular B sand and gravel fill material. Adverse weather conditions such as rain make the placement of engineered fill to the required degree of density difficult or impossible; engineered fill cannot be placed during freezing conditions, i.e. normally not between December and April of each year. The location of the foundations on the engineered fill pad is critical and certification by a qualified surveyor that the foundations are within the stipulated boundaries is mandatory. Since layout stakes are often damaged or removed during fill placement, offset stakes must be installed and maintained by the surveyors during the course of fill placement so that the contractor and engineering staff are continually aware of where the engineered fill limits lie. Excavations within the engineered fill pad must be backfilled with the same conditions and quality control as the original pad. To perform satisfactorily, engineered fill requires the cooperation of the designers, engineers, contractors and all parties must be aware of the requirements. The minimum requirements are as follows, however, the geotechnical report must be reviewed for specific information and requirements.. Prior to site work involving engineered fill, a site meeting to discuss all aspects must be convened. The surveyor, contractor, design engineer and geotechnical engineer must attend the meeting. At this meeting, the limits of the engineered fill will be defined. The contractor must make known where all fill material will be obtained from and samples must be provided to the geotechnical engineer for review, and approval before filling begins.. Detailed drawings indicating the lower boundaries as well as the upper boundaries of the engineered fill must be available at the site meeting and be approved by the geotechnical engineer.. The building footprint and base of the pad, including basements, garages, etc. must be defined by offset stakes that remain in place until the footings and service connections are all constructed. Confirmation that the footings are within the pad, service lines are in place, and that the grade conforms to drawings, must be obtained by the owner in writing from the surveyor and Sirati & Partners Consultants Limited (SPCL). Without this confirmation, no responsibility for the performance of the structure can be accepted by Sirati & Partners Consultants Limited. Survey drawing of the pre and post fill location and elevations will also be required. i