LEVELTON CONSULTANTS LTD. 1.0 Introduction. 2.0 Project Description. December 16, Levelton File # R

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1 LEVELTON CONSULTANTS LTD. Abbotsford Office Gladys Avenue Abbotsford, BC V2S 2E8 T: F: December 16, 2015 Levelton File # R Keil Street White Rock, BC V4B 4V6 Attention: Mr. Paul Slack Manager of Operations Project: Subject: Gordon Avenue Utility Upgrades, White Rock, BC Geotechnical Engineering Assessment Report Dear Sir, 1.0 Introduction Levelton Consultants Ltd. (Levelton) presents herein the results of our geotechnical site assessment to The Corporation of the (the City) for storm and sanitary utility upgrades on a portion of Gordon Avenue between Anderson Street and Oxford Street in White Rock, BC. The general location of the subject alignment of Gordon Avenue is shown on the attached Figure 1. We understand that replacement of the storm and sanitary sewers is considered necessary due to ground settlement in the area. The Levelton scope of work comprised of a desktop study of available information, subsurface explorations along the portion of Gordon Avenue described above, groundwater pump testing in monitoring wells, analysis of the collected information, and preparation of this report. The Levelton scope of work did not include assessment of the soil or groundwater at the project site with respect to environmental considerations or corrosion potential. 2.0 Project Description Levelton understands that pavement on Gordon Avenue between Anderson Street and Oxford Street (the site), existing utilities under the roadway, and the immediate surrounding area has experienced settlement that has become more pronounced within the last year. Recent surface expressions of differential settlement of up to

2 about 300 mm has occurred at nearby residential properties. The existing utilities along Gordon Avenue include sanitary, storm, and water mains, tie-ins, and manholes. We understand that, at this time, the City plans to replace the settled sanitary and storm mains and manholes at the site. Levelton was provided with civil drawings prepared by R.F. Binnie and Associates Ltd (Binnie drawing , dated October 05, 2015) showing the proposed work. The new sanitary sewer will be a 200 mm diameter PVC main, and the new storm sewer will be a 200 mm diameter PVC main. The drawings indicate that the invert of the planned sanitary main will be situated between 1.8 and 3.3 m below existing grade, and the invert of the planned storm main will be between 0.55 and 1.2 m below existing grade. The location of the planned sanitary and storm sewer main replacements is shown on the attached Figure 2. Profiles of the planned mains are shown on the attached Figures 3 and Field Work 3.1 Subsurface Explorations On October 21, 2015 Levelton advanced 4 (four) auger holes using a truck-mounted drill rig equipped with solidstem continuous flight augers to assess the soil and groundwater conditions at the project site with respect to geotechnical engineering considerations. The approximate locations of the auger holes are shown on the attached Figure 2. The auger holes extended to depths of between 6.1 and 9.1 m below grade. Dynamic Cone Penetration Tests (DCPTs) were conducted at the auger holes to assess the in-situ relative density / consistency of the soils. The soil and groundwater conditions encountered at the auger holes were logged in the field by a member of our geotechnical staff. Representative disturbed soil samples were collected from the auger flights for visual classification and moisture content determination purposes. The auger holes were closed in conformance with provincial groundwater protection requirements immediately upon completion of the investigation, and the asphalt at the auger holes was patched with cold-mix asphalt. Monitoring wells with a diameter of 50 mm were installed at auger holes AH15-01 and AH The monitoring well installation details are indicated on the relevant soil logs attached to this report. Both monitoring wells were equipped with a flush mounted cover to allow for future groundwater level readings and testing. Detailed descriptions of the soil and groundwater conditions encountered at the auger holes are provided on the soil logs attached to this report. The soil logs also graphically illustrate the moisture content of disturbed soil samples obtained from the auger flights and the recorded DCPT blow counts. A summary discussion of the soil and groundwater conditions encountered at the auger holes is provided below. Levelton File # R December 16, 2015 Gordon Avenue Utility Upgrades, White Rock, BC Geotechnical Engineering Assessment Report Page 2

3 3.2 Hydraulic Conductivity Testing Levelton completed a series of hydraulic conductivity (rising head) tests in the monitoring wells at AH15-01 and AH15-03 to determine the potential range of hydraulic conductivities (K) of the local soils for assessment of potential excavation dewatering requirements during construction. Three rising head tests were conducted at each monitoring well. The tests were performed using a Solinst Levelogger, rented from Pine Environmental. During the rising head tests, water was removed from the wells using a disposable PVC bailer to rapidly lower the water level in the wells. The rate at which the water level returned to its pre-test level was recorded. A summary discussion of the rising head test results is provided below. 4.0 Subsurface Conditions 4.1 Surficial Geology The Geological Survey of Canada surficial geology map covering the project area (Map 1484A) indicates that Gordon Avenue is underlain by Pleistocene Vashon Drift lodgement till with a sandy loam matrix, and minor flow till containing lenses and interbeds of glaciolacustrine laminated stony silt. 4.2 Levelton Auger holes The soils encountered in the Levelton auger holes were not consistent with the description provided on the surficial geology map. The following generalized soil profile was encountered at AH15-01 to AH15-04: Asphalt a surface layer of asphalt was encountered at all of the auger holes, ranging in thickness between 76 and 114 mm. Dense to very dense granular fill granular fill comprised of rounded sand and gravel was encountered below the asphalt at all of the auger holes. The granular fill was between 250 and 420 mm thick. Based on the DCPT blow counts, the granular fill was judged to be dense to very dense. The moisture content of a sample of the granular fill was 7 percent. Compact red vesicular pumice fill Red vesicular pumice fill was encountered below the granular fill in all of the auger holes. The pumice fill extended to between 0.9 and 1.0 m below grade, and was between 0.4 and 0.5 m thick. The pumice fill was judged to be compact based on the DCPT blow counts. The moisture content of samples of the red vesicular pumice ranged between 10 and 12 percent. Peat Fibrous peat was encountered at all of the Levelton boreholes ranging from 1.1 to 4.9 m thick. The peat extended to between 2.6 and 6.1 m below grade. The moisture content of samples taken from the peat layer ranged from 140 to 550 percent, indicating highly compressible conditions. Soft or loose silty sand / sandy silt (AH15-01 only) The peat was underlain by silty sand to sandy silt in AH This layer was judged to be soft or loose based on the DCPT blow counts. The thickness of this Levelton File # R December 16, 2015 Gordon Avenue Utility Upgrades, White Rock, BC Geotechnical Engineering Assessment Report Page 3

4 layer was about 2 m. The moisture content of samples taken from the silty sand / sandy silt layer ranged between 28 and 50 percent. A second 0.3 m thick layer of peat was encountered under the silty sand / sandy silt. Firm to stiff clayey silt (AH15-01 only) A 1.5 m thick layer of clayey silt was encountered below the lower peat layer in AH The clayey silt was judged to be firm to stiff based on the DCPT blow counts. The moisture content of a sample taken from the clayey silt was 41 percent. Compact to very dense silty sand / gravelly sand / sand and gravel Granular soils ranging from silty sand to sand and gravel were encountered below the peat in AH15-02, AH15-03 and AH15-04, and below the clayey silt in AH The granular soils extended to the bottom of the auger holes. The granular soils were judged to be compact to very dense based on the DCPT blow counts. Samples taken from these deposits had moisture contents ranging between 14 and 25 percent. All of the Levelton auger holes terminated in the dense mineral soils at depths ranging from 6.1 to 9.1 m below the road surface. 4.3 Groundwater Conditions Groundwater seepage was encountered at all of the auger holes between 1 and 1.2 m below grade at the time of drilling. Prior to conducting the hydraulic conductivity tests, Levelton staff measured the static water level in each well to establish pre-test conditions. Water level measurements are provided in Table 1. Table 1: Static Water Levels and Well Installation Details Well ID Screen Interval (1) (mbgs) Length of screen (1) (m) Depth to water (2) (m) End of hole (2) (m) Length of water column in the well (m) Position of the top of groundwater with respect to the screen AH Above the well screen AH Above the well screen (1) Obtained from monitoring well logs (2) Measured from top of pipe on November 24, 2015 Levelton analyzed the hydraulic conductivity test data using Aquifer Test Pro Ver software developed by Waterloo Hydrogeological Inc. The Hvorslev model was fit to the slug test data. Results of the hydraulic conductivity tests are presented in Table 2. Levelton File # R December 16, 2015 Gordon Avenue Utility Upgrades, White Rock, BC Geotechnical Engineering Assessment Report Page 4

5 Table 2: Results of Hydraulic Conductivity Tests Well ID Screened Soil Type Type of test conducted Hvorslev Method (K) (m/s) 4.5X10-7 AH15-01 (Test 1) AH15-01 (Test 2) AH15-01 (Test 3) Fibrous Peat, some wood fragments Silty Sand to sandy Silt, trace organics Fibrous peat Rising Head 4.5X X10-7 AH15-03 (Test 1) 2.0X10-6 AH15-03 (Test 2) Fibrous Peat, some wood fragments 2.0X10-6 AH15-03 (Test 3) 1.8X10-6 Geometric Mean (K) (m/s) 5.1 X X 10-6 Based on the results presented in Table 2, the hydraulic conductivity of the peat underlying Gordon Avenue ranged from 5 X 10-7 to 2 X 10-6 m/s. These values were similar to other hydraulic conductivity values that Levelton is familiar with, including: 5.5 X 10-7 m/s for undisturbed, amorphous peat around the Vancouver Landfill; and 2.5 X 10-7 and 3.5 X 10-6 m/s in two monitoring wells at the Vancouver Landfill. 5.0 Conclusions and Recommendations 5.1 General It is our opinion that the settlement of the Gordon Avenue roadway between Anderson Street and Oxford Street and the utilities in the roadway in the same area can be attributed to primary and secondary consolidation of the peat deposit of variable thickness located under the roadway. The primary consolidation of the peat in recent years is due to a fluctuating groundwater level resulting in altered effective stress in the soil. The secondary consolidation is due to the degradation / decomposition of the peat structure. It is anticipated that settlement of the peat will continue to occur, with accelerated settlement occurring whenever the groundwater table is lowered due to dewatering or natural groundwater fluctuations. The primary geotechnical challenges related to the installation of the sanitary and storm mains include trench excavation stability, excavation dewatering, and minimizing settlement of the surrounding area during or as a consequence of the planned construction. The fibrous structure of the encountered peats is beneficial from an excavation stability perspective, making it feasible to use conventional trench boxes to support vertical sidewall excavations. Furthermore, the Levelton rising head hydraulic conductivity testing indicates that the permeability of the peat is low (roughly comparable to silt to clayey silt), indicating that the groundwater inflow into the excavation will be limited, allowing the use of conventional sump and pump systems. While the rate of seepage is expected to be low, it is recommended that the duration the excavation remains open be kept to a minimum. This will reduce the potential for causing additional settlement to surrounding Levelton File # R December 16, 2015 Gordon Avenue Utility Upgrades, White Rock, BC Geotechnical Engineering Assessment Report Page 5

6 areas. Notwithstanding, it is strongly recommended that a pre-construction visual condition survey be completed on properties located within 30 m of the planned excavations. 5.2 Temporary Excavations Temporary unsupported excavations should conform to WorkSafe BC requirements where worker access is required. It is our opinion that the sides of unsupported temporary excavations deeper than 1.2 m should not be steeper than 1H:1V (Horizontal:Vertical) in the site soils. Flatter unsupported temporary excavation slopes may be required where groundwater seepage is encountered, or if loose / saturated backfill in existing adjacent utility trenches is exposed by the new excavations. It should also be noted that vibrations induced by adjacent traffic or construction equipment could result in sloughing of unsupported non-cohesive soils. The actual slope inclinations for unsupported excavations should be determined by a Geotechnical Engineer prior to allowing workers to approach or enter the excavation. Levelton anticipates that vertical trench excavations will be required to minimize the amount of disturbance to the adjacent pavement and properties. Levelton recommends that suitable trench shoring cages be used for excavations greater than 1.2 m deep in the site soils. The trench box style shoring cage with fixed bracing spans provides safety to the workers against trench-wall soil collapse, but does not actively shore the excavation sidewalls, unless firmly secured to the sidewalls to a suitable height to prevent sloughing. It has been our experience that failing to provide intimate contact between the trench shoring and the excavation sidewalls will result in an increased risk of nearby pavement distress and soil sloughing. It has also been our experience that Contractors prefer to leave space between the shoring boxes and the trench sidewalls. Failing to provide proper contact between the shoring and the trench-wall will likely result in excessive loss of material between the outside faces of the trench box and the excavation sidewalls, which could undermine the adjacent pavement or nearby underground services and increase the volume of backfill needed to restore grade. Rounded pea gravel, birds-eye gravel, or other materials may be used to backfill any void between the trench boxes and the trench walls to near the top of the trench, where necessary, to provide the stabilizing contact between the trench shoring and the soil sidewalls, immediately after placing the shoring cage. Alternatively, the Contractor should properly implement the use of shoring boxes with adjustable bracing lengths or shoring jacks to actively secure the shoring facing material to the trench sidewalls. The Contractor or the City should carry a contingency to address extra costs associated with reinstating sloughed excavations and repairs to adjacent pavements that result from leaving unsecured open vertical trenches or gaps between trench sidewalls and the shoring during the construction of the proposed sanitary and storm mains. We recommend that soil and material stockpiles be kept away from the edge of the excavation a horizontal distance at least equal to the depth of the excavation. It is expected that conventional excavation equipment can be used to excavate the soils along the length of the planned sanitary and storm mains. Levelton File # R December 16, 2015 Gordon Avenue Utility Upgrades, White Rock, BC Geotechnical Engineering Assessment Report Page 6

7 5.3 Temporary Excavation Dewatering The hydraulic conductivity tests results indicate that the peat encountered below the pavement structure will not transmit large volumes of groundwater under normal groundwater gradients. As such, we expect that surface water and groundwater seepage entering excavations could be adequately controlled using sumps and pumping. Specialized temporary dewatering measures are not expected to be necessary. Seepage pumped from excavations should be disposed of in accordance with requirements. The settlement effects associated with dewatering are time dependent, as it takes time to develop the full cone of depression that defines the drawn-down groundwater level in the soil. The longer the soil remains dewatered, the greater the settlement and footprint of the area impacted by dewatering. Consequently, it is recommended that the utility replacement be conducted over as short a time period as possible by an experienced contractor that understands the need for expediency. Furthermore, we do not recommend that the utility replacements be conducted during the dry summer months (mid-july through early October), as this may further exacerbate construction related settlement. It should be noted that, if excavations are advanced in close proximity to existing underground utility corridors with granular bedding and backfill, heavy groundwater seepage could be encountered from the existing backfill and bedding where exposed below the groundwater table. 5.4 Trench Subgrade Preparation and Trench Bedding Based on the auger holes and the expected depth of excavation required to install the planned sanitary and storm mains, it is anticipated that the soils at the base of the sanitary main trench will generally consist of peat, and the soils at the base of the storm main will generally consist of red vesicular pumice over peat. Where the subgrade consists of peat, we recommend that the subgrade be over-excavated a minimum of 300 mm below the invert of the pipe. The extent of such over-excavation should be confirmed on-site by the Geotechnical Engineer at the time of trench excavation. The over-excavated soils should be replaced with trench bedding comprised of light weight red vesicular pumice fill to minimize further settlement, and to limit disturbance to the subgrade during pipe installation. The light weight pumice fill should be fully wrapped with a non-woven geotextile separator, such as Nilex 4551 or equivalent. The red vesicular basalt pumice should have a maximum moist unit weight of 840 kg/m 3, have a gradation of 19 to 75 mm, and be free of foreign material such as sand, silt, and other fines not of volcanic origin. Where the subgrade consists of existing red vesicular pumice, the subgrade should be over-excavated a minimum of 150 mm below the invert of the pipe followed by reinstating with the same type of lightweight fill. The exposed pumice subgrade should be nominally compacted with light compaction equipment such as a 500 pound vibratory plate tamper. Levelton File # R December 16, 2015 Gordon Avenue Utility Upgrades, White Rock, BC Geotechnical Engineering Assessment Report Page 7

8 5.5 Trench Backfill The trench backfill should also consist of the imported light weight red vesicular pumice, as described above, fully wrapped with a non-woven geotextile separator such as Nilex 4551 or equivalent. The pumice should be placed in 300 mm thick lifts and be compacted with light weight equipment such as a 500 lb. vibratory plate tamper. A minimum of three passes with the light weight equipment should be made over each lift. Over compaction of the backfill, or the use of heavy compaction equipment, can lead to particle breakage and an increase in fines content without any beneficial gain in compaction levels. 5.6 Pavement Restoration Restoration of the pavement where excavation has been completed should be conducted in accordance with the appropriate road standards. At a minimum, we recommend that the pavement structure at excavations consist of the following: 75 mm of asphalt, underlain by 150 mm of 19 mm minus crushed gravel base course; underlain by 250 mm of 75 mm minus pit run sand and gravel sub-base course; underlain by Light weight red vesicular pumice, fully wrapped with geotextile as described above. We recommend that the base and sub-base courses conform to the specifications for these materials contained in MMCD Volume II. They should be placed in discrete lifts a maximum of 300 mm in thickness at within 2 percent of their optimum moisture content for compaction and be compacted to not less than 95 percent of their Modified Proctor Maximum Dry Density, as confirmed by in-place soil density testing. 5.7 Settlement The peat below the sanitary and storm mains will continue to settle due to secondary consolidation and potential future groundwater fluctuation effects. The thickness of the peat is estimated, based on the Levelton boreholes, to range from 0 m to 4 m under the sanitary main and from 2.8 m to 5.2 m under the storm main. We estimate that the peat could settle up to 200 mm under the sanitary main, and up to 300 mm under the storm main, over 50 years after installation. As complete removal of the peat is not practical, we recommend that the design of the sanitary main account for potential differential settlement of 200 mm over a horizontal distance of 30 m, and the storm main design account for potential differential settlement of 150 mm over a horizontal distance of 20 m. 6.0 Geotechnical Review We recommend that the Geotechnical Engineer review the following during construction: Temporary unsupported excavation slopes; Trench and pavement structure subgrades; Imported pipe bedding and trench backfill materials; Levelton File # R December 16, 2015 Gordon Avenue Utility Upgrades, White Rock, BC Geotechnical Engineering Assessment Report Page 8

9 Pavement sub-base and base course materials; and Placement and compaction of pipe bedding, trench backfill, and pavement sub-base and base courses. As described above, it should be the Contractor s responsibility to design and implement appropriate shoring for trenches. 7.0 Closure This geotechnical engineering assessment report has been prepared by Levelton Consultants Ltd. exclusively for the. The opinions and recommendations provided in this report reflect our judgement in light of the information provided to us at the time that it was prepared. Any use of this report by third parties, or any reliance on or decisions made based on it, are the responsibility of such third parties. Levelton does not accept responsibility for damages suffered, if any, by a third party as a result of their use of or reliance on this report. The soil logs attached to this report provide description of the soil and groundwater conditions encountered at discrete auger hole locations. Actual soil conditions in areas remote from the auger holes may vary along the road alignment. Contractors should make their own interpretation of the soil logs and the site conditions for the purposes of bidding and performing work at the site. The attached Terms of Reference form an integral part of this report. We trust the information provided herein meets your immediate requirements. If you have any questions or require additional information, please contact the undersigned. Levelton Consultants Ltd. ORIGINAL SIGNED BY: ORIGINAL SIGNED BY: Per: Calum Buchan, P.E., P.Eng. Per: Phil VanLaar, EIT Senior Geotechnical Engineer Geotechnical Engineer-in-Training Reviewed by: Michael Gutwein, P.Eng. Senior Geotechnical Engineer Attachments: Terms of Reference Figures 1-4 Soil Logs Levelton File # R December 16, 2015 Gordon Avenue Utility Upgrades, White Rock, BC Geotechnical Engineering Assessment Report Page 9

10 TERMS OF REFERENCE FOR GEOTECHNICAL REPORTS ISSUED BY LEVELTON CONSULTANTS LTD. 1. STANDARD OF CARE Levelton Consultants Ltd. ( Levelton ) prepared and issued this geotechnical report (the Report ) for its client (the Client ) in accordance with generally-accepted engineering consulting practices for the geotechnical discipline. No other warranty, expressed or implied, is made. Unless specifically stated in the Report, the Report does not address environmental issues. The terms of reference for geotechnical reports issued by Levelton (the Terms of Reference ) contained in the present document provide additional information and caution related to standard of care and the use of the Report. The Client should read and familiarize itself with these Terms of Reference. 2. COMPLETENESS OF THE REPORT All documents, records, drawings, correspondence, data, files and deliverables, whether hard copy, electronic or otherwise, generated as part of the services for the Client are inherent components of the Report and, collectively, form the instruments of professional services (the Instruments of Professional Services ). The Report is of a summary nature and is not intended to stand alone without reference to the instructions given to Levelton by the Client, the communications between Levelton and the Client, and to any other reports, writings, proposals or documents prepared by Levelton for the Client relative to the specific site described in the Report, all of which constitute the Report. TO PROPERLY UNDERSTAND THE INFORMATION, OBSERVATIONS, FINDINGS, SUGGESTIONS, RECOMMENDATIONS AND OPINIONS CONTAINED IN THE REPORT, REFERENCE MUST BE MADE TO THE WHOLE OF THE REPORT. LEVELTON CANNOT BE RESPONSIBLE FOR USE BY ANY PARTY OF PORTIONS OF THE REPORT WITHOUT REFERENCE TO THE WHOLE REPORT AND ITS VARIOUS COMPONENTS. 3. BASIS OF THE REPORT Levelton prepared the Report for the Client for the specific site, development, building, design or building assessment objectives and purpose that the Client described to Levelton. The applicability and reliability of any of the information, observations, findings, suggestions, recommendations and opinions contained in the Report are only valid to the extent that there was no material alteration to or variation from any of the said descriptions provided by the Client to Levelton unless the Client specifically requested Levelton to review and revise the Report in light of such alteration or variation. 4. USE OF THE REPORT The information, observations, findings, suggestions, recommendations and opinions contained in the Report, or any component forming the Report, are for the sole use and benefit of the Client and the team of consultants selected by the Client for the specific project that the Report was provided. NO OTHER PARTY MAY USE OR RELY UPON THE REPORT OR ANY PORTION OR COMPONENT WITHOUT THE WRITTEN CONSENT OF LEVELTON. Levelton will consent to any reasonable request by the Client to approve the use of this Report by other parties designated by the Client as the Approved Users. As a condition for the consent of Levelton to approve the use of the Report by an Approved User, the Client must provide a copy of these Terms of Reference to that Approved User and the Client must obtain written confirmation from that Approved User that the Approved User will comply with these Terms of Reference, such written confirmation to be provided separately by each Approved User prior to beginning use of the Report. The Client will provide Levelton with a copy of the written confirmation from an Approved User when it becomes available to the Client, and in any case, within two weeks of the Client receiving such written confirmation. The Report and all its components remain the copyright property of Levelton and Levelton authorises only the Client and the Approved Users to make copies of the Report, but only in such quantities as are reasonably necessary for the use of the Report by the Client and the Approved Users. The Client and the Approved Users may not give, lend, sell or otherwise disseminate or make the Report, or any portion thereof, available to any party without the written permission of Levelton. Any use which a third party makes of the Report, or any portion of the Report, is the sole responsibility of such third parties. Levelton accepts no responsibility for damages suffered by any third party resulting from the use of the Report. The Client and the Approved Users acknowledge and agree to indemnify and hold harmless Levelton, its officers, directors, employees, agents, representatives or sub-consultants, or any or all of them, against any claim of any nature whatsoever brought against Levelton by any third parties, whether in contract or in tort, arising or related to the use of contents of the Report. Version 5 - March 09, 2007 Page 1 of 2

11 TERMS OF REFERENCE FOR GEOTECHNICAL REPORTS ISSUED BY LEVELTON CONSULTANTS LTD. (continued) 5. INTERPRETATION OF THE REPORT a. Nature and Exactness of Descriptions: The classification and identification of soils, rocks and geological units, as well as engineering assessments and estimates have been based on investigations performed in accordance with the standards set out in Paragraph 1 above. The classification and identification of these items are judgmental in nature and even comprehensive sampling and testing programs, implemented with the appropriate equipment by experienced personnel, may fail to locate some conditions. All investigations or assessments utilizing the standards of Paragraph 1 involve an inherent risk that some conditions will not be detected and all documents or records summarizing such investigations will be based on assumptions of what exists between the actual points sampled. Actual conditions may vary significantly between the points investigated and all persons making use of such documents or records should be aware of, and accept, this risk. Some conditions are subject to changes over time and the parties making use of the Report should be aware of this possibility and understand that the Report only presents the conditions at the sampled points at the time of sampling. Where special concerns exist, or when the Client has special considerations or requirements, the Client must disclose them to Levelton so that additional or special investigations may be undertaken, which would not otherwise be within the scope of investigations made by Levelton or the purposes of the Report. b. Reliance on information: The evaluation and conclusions contained in the Report have been prepared on the basis of conditions in evidence at the time of site investigation and field review and on the basis of information provided to Levelton. Levelton has relied in good faith upon representations, information and instructions provided by the Client and others concerning the site. Accordingly, Levelton cannot accept responsibility for any deficiency, misstatement or inaccuracy contained in the report as a result of misstatements, omissions, misrepresentations or fraudulent acts of persons providing information. c. Additional Involvement by Levelton: To avoid misunderstandings, Levelton should be retained to assist other professionals to explain relevant engineering findings and to review the geotechnical aspects of the plans, drawings and specifications of other professionals relative to the engineering issues pertaining to the geotechnical consulting services provided by Levelton. To ensure compliance and consistency with the applicable building codes, legislation, regulations, guidelines and generally-accepted practices, Levelton should also be retained to provide field review services during the performance of any related work. Where applicable, it is understood that such field review services must meet or exceed the minimum necessary requirements to ascertain that the work being carried out is in general conformity with the recommendations made by Levelton. Any reduction from the level of services recommended by Levelton will result in Levelton providing qualified opinions regarding adequacy of the work. 6. ALTERNATE REPORT FORMAT When Levelton submits both electronic and hard copy versions of the Instruments of Professional Services, the Client agrees that only the signed and sealed hard copy versions shall be considered final and legally binding upon Levelton. The hard copy versions submitted by Levelton shall be the original documents for record and working purposes, and, in the event of a dispute or discrepancy, the hard copy versions shall govern over the electronic versions; furthermore, the Client agrees and waives all future right of dispute that the original hard copy signed and sealed versions of the Instruments of Professional Services maintained or retained, or both, by Levelton shall be deemed to be the overall originals for the Project. The Client agrees that the electronic file and hard copy versions of Instruments of Professional Services shall not, under any circumstances, no matter who owns or uses them, be altered by any party except Levelton. The Client warrants that the Instruments of Professional Services will be used only and exactly as submitted by Levelton. The Client recognizes and agrees that Levelton prepared and submitted electronic files using specific software or hardware systems, or both. Levelton makes no representation about the compatibility of these files with the current or future software and hardware systems of the Client, the Approved Users or any other party. The Client further agrees that Levelton is under no obligation, unless otherwise expressly specified, to provide the Client, the Approved Users and any other party, or any or all of them, with specific software and hardware systems that are compatible with any electronic submitted by Levelton. The Client further agrees that should the Client, an Approved User or a third party require Levelton to provide specific software or hardware systems, or both, compatible with the electronic files prepared and submitted by Levelton, for any reason whatsoever included but not restricted to an order from a court, then the Client will pay Levelton for all reasonable costs related to the provision of the specific software or hardware systems, or both. The Client further agrees to indemnify and hold harmless Levelton, its officers, directors, employees, agents, representative or sub-consultant, or any or all of them, against any claim or any nature whatsoever brought against Levelton, whether in contract or in tort, arising or related to the provision or use or any specific software or hardware provided by Levelton. Version 5 - March 09, 2007 Page 2 of 2

12 NORTH SITE LOCATION REVISIONS DESIGN: DATE: ADAPTED FROM: WHITE ROCK ONLINE MAP PROJECT/DWG. NO: TITLE: SITE LOCATION PLAN - CB SEAL: CHECK: - SCALE: DEC 2015 NTS REV Date Issue/Revision Description Drawn Check DATE: 2015 This drawing is the sole property of Levelton Consultants Ltd. and cannot be used or duplicated in any way without the expressed written consent of Levelton Consultants. The general contractor shall verify all dimensions and report any discrepancies to Levelton Consultants Ltd. PROJECT: ADDRESS: CLIENT: GORDON AVENUE ROAD AND UTILITIES REPAIR GORDON AVENUE, WHITE ROCK, BC THE CITY OF WHITE ROCK LEVELTON DRAWN: FIG. NO: PV FILE NO: R

13 NORTH PLANNED SANITARY SEWER AH15-01 AH15-02 AH15-03 AH15-04 PLANNED STORM SEWER LEGEND AH15-02 AUGER HOLE LOCATIONS AH15-01 AUGER HOLE WITH WELL LOCATIONS NOTE: LOCATIONS ARE APPROXIMATE DESIGN: REVISIONS DATE: TITLE: ADAPTED FROM: R.F. BINNIE S1 PROJECT: 10 / 99 REV Date Issue/Revision Description Drawn Check This drawing is the sole property of Levelton Consultants Ltd. and cannot be used or duplicated in any way without the expressed written consent of Levelton Consultants. The general contractor shall verify all dimensions and report any discrepancies to Levelton Consultants Ltd. - SITE AND AUGERHOLE PLAN PROJECT/DWG. NO: DATE: SEAL: ADDRESS: CLIENT: CHECK: CB DRAWN: GORDON AVENUE ROAD AND UTILITIES REPAIR GORDON AVENUE, WHITE ROCK, BC THE CITY OF WHITE ROCK DEC 2015 SCALE: PV FIG. NO: LEVELTON NTS FILE NO: R

14 ELEVATION (m) APPROXIMATE TOP OF PEAT PROFILE (2015) 1.0 PLANNED SANITARY SEWER PROFILE APPROXIMATE BOTTOM OF PEAT PROFILE (2015) -3.0 AH AH15-02 AH DESIGN: REVISIONS AH15-01 DATE: TITLE: ADAPTED FROM: R.F. BINNIE S1 PROJECT: REV Date Issue/Revision Description Drawn Check This drawing is the sole property of Levelton Consultants Ltd. and cannot be used or duplicated in any way without the expressed written consent of Levelton Consultants. The general contractor shall verify all dimensions and report any discrepancies to Levelton Consultants Ltd. - SANITARY SEWER MAIN AND PEAT PROFILE PROJECT/DWG. NO: DATE: SEAL: ADDRESS: CLIENT: CHECK: CB DRAWN: GORDON AVENUE ROAD AND UTILITIES REPAIR GORDON AVENUE, WHITE ROCK, BC THE CITY OF WHITE ROCK DEC 2015 SCALE: PV FIG. NO: LEVELTON NTS FILE NO: R

15 ELEVATION (m) APPROXIMATE TOP OF PEAT PROFILE (2015) PLANNED STORM SEWER PROFILE APPROXIMATE BOTTOM OF PEAT PROFILE (2015) -3.0 AH AH15-02 AH DESIGN: REVISIONS AH15-01 DATE: TITLE: ADAPTED FROM: R.F. BINNIE D1 PROJECT: REV Date Issue/Revision Description Drawn Check This drawing is the sole property of Levelton Consultants Ltd. and cannot be used or duplicated in any way without the expressed written consent of Levelton Consultants. The general contractor shall verify all dimensions and report any discrepancies to Levelton Consultants Ltd. - STORM SEWER MAIN AND PEAT PROFILE PROJECT/DWG. NO: DATE: SEAL: ADDRESS: CLIENT: CHECK: CB DRAWN: GORDON AVENUE ROAD AND UTILITIES REPAIR GORDON AVENUE, WHITE ROCK, BC THE CITY OF WHITE ROCK DEC 2015 SCALE: PV FIG. NO: LEVELTON NTS FILE NO: R

16 Depth (m) (ft) 2 4 Levelton Consultants Ltd. # Gladys Avenue Abbotsford, B.C. V2S 2E8 Tel: Fax: Description ASPHALT - 95 mm thick dense, brown, SAND and GRAVEL, rounded gravel, moist, fill compact, red, sandy gravel VESICULAR PUMICE, moist, fill brown, fibrous PEAT, some wood fragments, wet Gordon Avenue Sewer Replacement Gordon Avenue White Rock Well 1 C N Type/ Sample # G1 G2 G3 Water Level P1 Oct AH15-01 Pg 1 of 1 Project No: R Drilled MC = 140.2% 6 2 G4 MC = 404% 8 10 G5 MC = 520% soft/loose, grey, silty SAND to sandy SILT, trace organics, wet G6 16 G7 18 G brown, fibrous PEAT, wet firm to stiff, grey, clayey SILT, trace sand, trace organics, moist G9 MC = 275.2% 22 G10 1 LOG PER PAGE R SOIL LOGS - OCT GPJ LEVELTON.GDT 15/12/ C: Condition of Sample Good Disturbed No Recovery compact, grey, silty SAND, trace organics, wet dense, brown, SAND and GRAVEL, coarse sand, fine subangular gravel, wet groundwater encountered at 1.2 m below surrounding grade. Bottom of hole at 9.1 metres Type: Type of Sampler SPT : 2 in. standard ST : Shelby G : Grab CORE SOIL CLASSIFICATION IN ACCORDANCE WITH THE CANADIAN FOUNDATION ENGINEERING MANUAL 4TH EDITION THIS LOG IS FOR GEOTECHNICAL PURPOSES ONLY THIS LOG IS THE SOLE PROPERTY OF LEVELTON CONSULTANTS LTD AND CANNOT BE USED OR DUPLICATED IN ANY WAY WITHOUT EXPRESS WRITTEN PERMISSION. N: Number of Blows WH : Weight of Hammer WR : Weight of Rod Standard Penetration Test : ASTM D1586 Hammer Type: Trip Hammer DYNAMIC CONE PENETRATION TEST G11 G12 Plastic Limit (%) PP Liquid Limit (%) Moisture Content (%) Ground Water Level Shear strength in kpa (Torvane) Pocket Penetrometer (compressive strength in kpa) Shear strength in kpa (Unconfined) Shear strength in kpa (Field vane) Remolded strength in kpa Percent Passing # 200 sieve Bentonite/Grout Plug Solid Pipe Cuttings Slotted Pipe Sand/Pea-Gravel Drill Method: Solid Stem Auger / DCPT Date Drilled: 21/10/2015 Logged by: PV Checked by: CB

17 Depth (m) (ft) 2 4 Levelton Consultants Ltd. # Gladys Avenue Abbotsford, B.C. V2S 2E8 Tel: Fax: ASPHALT - 90 mm thick Description dense, brown, SAND and GRAVEL, rounded gravel, moist, fill compact, red, gravel VESICULAR PUMICE, moist, fill very loose, dark brown, PEAT and GRAVEL, well graded gravel, trace to some sand, moist to wet Gordon Avenue Sewer Replacement Gordon Avenue White Rock C N Type/ Sample # G1 Water Level P1 Oct AH15-02 Pg 1 of 1 Project No: R dark brown, fibrous PEAT, some wood fragments, wet G2 MC = 173.1% 8 10 G3 MC = 515.5% soft, brown, organic SILT, moist brown, amorphous PEAT, some silt, trace clay, wet G4 G5 MC = 544.2% MC = 126% 16 G6 MC = 198.2% very loose, dark brown, PEAT and GRAVEL, rounded gravel, trace sand, wet G7 G8 MC = 112.9% MC = 116.9% 22 dense, grey, SAND and GRAVEL, well graded sand, rounded gravel, wet G9 1 LOG PER PAGE R SOIL LOGS - OCT GPJ LEVELTON.GDT 15/12/ C: Condition of Sample Good Disturbed No Recovery groundwater encountered at 0.8 m below surrounding grade. Bottom of hole at 7.6 metres Type: Type of Sampler SPT : 2 in. standard ST : Shelby G : Grab CORE SOIL CLASSIFICATION IN ACCORDANCE WITH THE CANADIAN FOUNDATION ENGINEERING MANUAL 4TH EDITION THIS LOG IS FOR GEOTECHNICAL PURPOSES ONLY THIS LOG IS THE SOLE PROPERTY OF LEVELTON CONSULTANTS LTD AND CANNOT BE USED OR DUPLICATED IN ANY WAY WITHOUT EXPRESS WRITTEN PERMISSION. N: Number of Blows WH : Weight of Hammer WR : Weight of Rod Standard Penetration Test : ASTM D1586 Hammer Type: Trip Hammer DYNAMIC CONE PENETRATION TEST Plastic Limit (%) PP Liquid Limit (%) Moisture Content (%) Ground Water Level Shear strength in kpa (Torvane) Pocket Penetrometer (compressive strength in kpa) Shear strength in kpa (Unconfined) Shear strength in kpa (Field vane) Remolded strength in kpa Percent Passing # 200 sieve Drill Method: Solid Stem Auger / DCPT Date Drilled: 21/10/2015 Logged by: PV Checked by: CB

18 Depth (m) (ft) 2 4 Levelton Consultants Ltd. # Gladys Avenue Abbotsford, B.C. V2S 2E8 Tel: Fax: Description ASPHALT mm thick very dense, brown, SAND and GRAVEL, rounded gravel, moist, fill compact, red, sandy gravel VESICULAR PUMICE, moist, fill dark brown, fibrous PEAT, some wood fragments, wet Gordon Avenue Sewer Replacement Gordon Avenue White Rock Well 1 C N Type/ Sample # G1 G2 Water Level P1 Oct AH15-03 Pg 1 of 1 Project No: R MC = 151.3% 6 2 G3 MC = 387.9% 8 10 G4 MC = 497.3% 12 G5 MC = 541% 4 14 G6 MC = 551.4% G7 MC = 254.4% 6 20 dark brown, PEAT and GRAVEL, subrounded gravel, wet compact to very dense, grey, SAND and GRAVEL, coarse sand, rounded gravel, wet G8 G LOG PER PAGE R SOIL LOGS - OCT GPJ LEVELTON.GDT 15/12/ C: Condition of Sample Good Disturbed No Recovery groundwater encountered at 0.9 m below surrounding grade. Bottom of hole at 7.6 metres Type: Type of Sampler SPT : 2 in. standard ST : Shelby G : Grab CORE SOIL CLASSIFICATION IN ACCORDANCE WITH THE CANADIAN FOUNDATION ENGINEERING MANUAL 4TH EDITION THIS LOG IS FOR GEOTECHNICAL PURPOSES ONLY THIS LOG IS THE SOLE PROPERTY OF LEVELTON CONSULTANTS LTD AND CANNOT BE USED OR DUPLICATED IN ANY WAY WITHOUT EXPRESS WRITTEN PERMISSION. N: Number of Blows WH : Weight of Hammer WR : Weight of Rod Standard Penetration Test : ASTM D1586 Hammer Type: Trip Hammer DYNAMIC CONE PENETRATION TEST Plastic Limit (%) PP Liquid Limit (%) Moisture Content (%) Ground Water Level Shear strength in kpa (Torvane) Pocket Penetrometer (compressive strength in kpa) Shear strength in kpa (Unconfined) Shear strength in kpa (Field vane) Remolded strength in kpa Percent Passing # 200 sieve Bentonite/Grout Plug Solid Pipe Cuttings Slotted Pipe Sand/Pea-Gravel Drill Method: Solid Stem Auger / DCPT Date Drilled: 21/10/2015 Logged by: PV Checked by: CB

19 Depth (m) (ft) 2 4 Levelton Consultants Ltd. # Gladys Avenue Abbotsford, B.C. V2S 2E8 Tel: Fax: ASPHALT - 76 mm thick Description very dense, brown, SAND and GRAVEL, rounded gravel, moist, fill compact, red, sandy gravel VESICULAR PUMICE, moist, fill dark brown, fibrous PEAT, some wood fragments, wet Gordon Avenue Sewer Replacement Gordon Avenue White Rock C N Type/ Sample # G1 Water Level P1 Oct AH15-04 Pg 1 of 1 Project No: R MC = 255.8% 2 6 G2 MC = 154.5% 8 10 dark brown, PEAT and GRAVEL, subrounded gravel, wet compact to very dense, grey, SAND and GRAVEL, coarse sand, rounded gravel, wet compact, grey, gravelly SAND, some silt to silty, wet G3 G4 12 G G dark brown, organic SILT, wet compact to dense, grey, silty SAND, trace to some gravel, fine grained sand, wet groundwater encountered at 1.2 m below surrounding grade. Bottom of hole at 6.1 metres G7 G8 1 LOG PER PAGE R SOIL LOGS - OCT GPJ LEVELTON.GDT 15/12/ C: Condition of Sample Good Disturbed No Recovery Type: Type of Sampler SPT : 2 in. standard ST : Shelby G : Grab CORE SOIL CLASSIFICATION IN ACCORDANCE WITH THE CANADIAN FOUNDATION ENGINEERING MANUAL 4TH EDITION THIS LOG IS FOR GEOTECHNICAL PURPOSES ONLY THIS LOG IS THE SOLE PROPERTY OF LEVELTON CONSULTANTS LTD AND CANNOT BE USED OR DUPLICATED IN ANY WAY WITHOUT EXPRESS WRITTEN PERMISSION. N: Number of Blows WH : Weight of Hammer WR : Weight of Rod Standard Penetration Test : ASTM D1586 Hammer Type: Trip Hammer DYNAMIC CONE PENETRATION TEST Plastic Limit (%) PP Liquid Limit (%) Moisture Content (%) Ground Water Level Shear strength in kpa (Torvane) Pocket Penetrometer (compressive strength in kpa) Shear strength in kpa (Unconfined) Shear strength in kpa (Field vane) Remolded strength in kpa Percent Passing # 200 sieve Drill Method: Solid Stem Auger / DCPT Date Drilled: 21/10/2015 Logged by: PV Checked by: CB