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1 paterson consulting engineers -MEMO to: Minto Communities Inc. - Mr. Barry Gray bgray@minto.com cc: Minto Communities Inc. - Mr. Julio Da Silva julio_dasilva@minto.com re: Grade Raise Recommendations Clarke Lands Residential Development, Ottawa date: March, 011 pages: page memo, 6 pages of attachments and drawings files: PG198-MEMO.01 from: Andy Tovell 1.0 Introduction This memo provides grade raise recommendations concerning the Clarke Lands development at Strandherd and Cedarview Roads in Ottawa. Presently clean fill materials from the Chapman Mills development are being dumped and spread within the northeast part of the property off Waterlilly Way. Our recommendations can be used to direct the filling operations to produce the desired effect. It is our understanding that preliminary grading is not available. The grade raise recommendations can be used to provide the geotechnical constraints of the development parcel for the civil engineering consultants to design the site towards the best grading balance possible. Paterson Group has recently completed eight (8) boreholes within the central and west part of the Clarke Lands property to supplement the six (6) boreholes put down within the east part of the property and detailed in our Report No. PG198-1, dated September, 010. Factual information from previous investigations on and adjacent to the subject development has also been included in our assessment. The major part of the previous work was detailed in Paterson File PG0706-1, dated February 16, 006. A full compilation geotechnical report will be forthcoming upon completion of the current testing program. The current memo includes the results of twelve (1) consolidation tests from the recent borehole program. Six (6) additional consolidation tests are in progress as of this writing. The sample numbers and available preliminary results of the latter tests are tabulated along with the other test results, but the full test data is not yet available..0 Subsurface Conditions Reference should be made to the above-noted reports for the borehole logs for the previous investigative works. The logs for the current boreholes, numbered BH 7 to BH 1, inclusive are attached to this memo. At each of BH 7 and BH 1 it was considered prudent to drill a sister borehole beside the main borehole in order to recover additional samples. These holes are numbered BH 7B and BH 1B, respectively.

2 Minto Communities Inc. File No. PG198-MEMO.01 Page Split spoon samples, along with the Standard Penetration Test, were recovered of the stiff clay crust and sand, where present, at the depths indicated for samples on the logs. Shelby tube samples were recovered using a piston sampler at the depths indicated for samples on the logs. A field vane was used to determine the undrained shear strength profile. In each hole a cone was pushed and driven to practical refusal to infer the location of the bedrock. A tabular summary of several subsurface characteristics is provided in the attached Tables 1A and 1B. The locations of the current and previous boreholes are shown on the attached Test Hole Location Plan, Drawing No. PG198-. The available results of the consolidation tests are summarized in the attached Tables A and B. Charts showing the shear strength and preconsolidation pressure profiles with respect to elevation (Figures 1 and ) and depth (Figures and ) are attached. The consolidation test curve plots will be provided with the compilation geotechnical report. The recorded groundwater levels in the current and previous boreholes are summarized in the attached Table..0 Grading Considerations Analyses were carried out by this firm to estimate the available overconsolidation potential in order to provide recommendations for grade raise limits. These analyses were based on the following criteria: Analyses considered a long-term low groundwater level at. m depth and a postdevelopment groundwater drawdown of 0. m. Note the mean of the recorded groundwater levels in Table is 1.0 m depth. Analyses used approximately 80 of the estimated soil overconsolidation, based on the consolidation tests and a mean Cu/p c ratio of 0. for vane test results. Analyses modelled sustained foundation wall loads of 0 kpa on a 0.9 m wide footing (i.e. sustained foundation wall loads of kn/m). Analyses for conventional slab-on-fill garage construction assumed garage fill having a unit weight of 1 kn/m. Analyses for conditions where lightweight fill (LWF) material is used under the garage and porch slabs-on-grade assumed 1. m of the LWF would be used. LWF consists of expanded polystyrene foam (EPS). Based on geotechnical considerations, and the above-noted criteria, permissible grade raises for conventional (i.e. no LWF) construction, and construction where LWF is used within the garage and porch cavities have been determined at each borehole location and are summarized in Tables A and B, on the following pages. Both the thickness of the grade raise, above original ground level, and the finished grade at the permissible grade raise, are provided in the tables.

3 Minto Communities Inc. File No. PG198-MEMO.01 Page Table A: Permissible Grade Raises - Clarke Lands - East Part Borehole Number Original Ground Elevation Permissible Grade Raise Conventional LWF in Garage and Porch Thickness Fin. Grade Thickness Fin. Grade BH BH BH BH BH BH BH BH BH BH BH BH BH BH Permissible Grade raises are estimated at a typical house using: the available consolidation test information; interpretation of the available shear strength test results; 80 of available preconsolidation pressure; long-term low groundwater level at. m depth and additional post-development groundwater lowering of 0. m; an assumed grade raise fill unit weight of 18 kn/m ; stresses typical of conventional slab-on-fill garage construction, including footing loads representing a sustained foundation wall load of kn/m; and use of up to 1. m thickness of EPS - LWF in garages and porches for LWF case. The basic grade raise limits for conventional construction, as well as those for the use of LWF within the garage and porch cavities (i.e. no exterior LWF), are referenced with respect to the garage floor slab level of the houses, as this is the most critical grading condition for the structures, in terms of differential settlement, for conventional slab-on-fill garage construction.

4 Minto Communities Inc. File No. PG198-MEMO.01 Page The recommended basic permissible grade raise is limited by settlement of the garage footings because of the influence of the garage fill weight in combination with the garage footing loads. As such, the basic grade raise can be exceeded if techniques, such as the use of LWF, are used to reduce the settlement of the garage. The permissible grade raise information is also presented on the attached Permissible Grade Raise Plan, Drawing No. PG198-. Table B: Permissible Grade Raises - Clarke Lands - West Part Borehole Number Original Ground Elevation Permissible Grade Raise Conventional LWF in Garage and Porch Thickness Fin. Grade Thickness Fin. Grade BH BH BH BH BH BH BH BH BH BH BH BH BH BH BH Refer to Table A for notes regarding grade raise interpretation..0 Pre-Development Fill Placement Clean fill materials are available from the nearby Chapman Mills development. This material is presently being dumped on the property from access off Waterlilly Way. The zoning and height of the site filling can be established using the following considerations:

6 Test Hole Number Ground Elevation TABLE 1A: SUMMARY OF SUBSURFACE INFORMATION FOR CLARKE LANDS - EAST Strandherd Road at Cedarview Road, Ottawa (Nepean), Ontario Underside of Stiff Clay Crust Underside of Clay Inferred Bedrock Surface Level Depth Elevation Depth Elevation Depth Elevation BH BH BH BH BH BH BH >10.67 <8. BH >1.80 <80.1 BH >10. <8.6 BH BH >10.06 <8.1 BH >11.8 <81.8 BH >1.80 <80. BH >11.8 <81.9 Note: 1. Inferred bedrock surface is the depth of practical refusal of the dynamic cone penetration test (DCPT). All other boreholes terminated in an inferred glacial till stratum.

7 Test Hole Number Ground Elevation TABLE 1B: SUMMARY OF SUBSURFACE INFORMATION FOR CLARKE LANDS - WEST Strandherd Road at Cedarview Road, Ottawa (Nepean), Ontario Underside of Stiff Clay Crust Underside of Clay Inferred Bedrock Surface Level Depth Elevation Depth Elevation Depth Elevation BH BH BH BH BH BH BH BH BH >1.80 <79.1 BH >1.80 <79. BH >1. <76.6 BH >1.9 <80.0 BH >1.70 <76.7 BH >1.19 <80.0 BH Note: 1. BH 7 encountered fill at ground surface. The original ground elevation at BH 7 is inferred to be 9.8 m.. Inferred bedrock surface is the depth of practical refusal of the dynamic cone penetration test (DCPT). All other boreholes terminated in an inferred glacial till stratum.

8 TABLE A SUMMARY OF CONSOLIDATION TEST RESULTS - CLARKE LANDS - EAST Strandherd Road at Cedarview Road, Ottawa (Nepean), Ontario Sample No. Ground Elev. Depth Elevation p' c (kpa) p' o (kpa) O.C. (kpa) Ccr Cc W.C. () Sample Quality Clarke Lands Stage Testing Program: BH A BH A BH P BH A BH A BH P Clarke Lands Preliminary - 00 Testing Program: BH F BH G BH G Barrhaven Mews - 00 & 007 Testing Programs: BH P BH A BH G Notes: 1. Effective overburden pressure, p' o, is based on an average crust thickness of.0 m, an estimated long-term low groundwater depth of. m and a mean unit weight for the grey clay of 16.0 kn/m. The original ground elevation is used for p' o estimates.. The last column presents the quality assessment of the test sample: G = Good A = Acceptable P = Poor (Likely Disturbed)

9 Sample No. Ground Elev. TABLE B: SUMMARY OF CONSOLIDATION TEST RESULTS - CLARKE LANDS - WEST Depth Clarke Lands Stage Testing Program: Elevation p' c (kpa) p' o (kpa) BH O.C. (kpa) Ccr Cc W.C. () BH A BH BH BH A-P BH A-P BH A Sample Quality BH Disturbed BH BH A-P BH BH G BH G BH A-P BH A BH1B A BH BH Disturbed Clarke Lands Preliminary - 00 Testing Program: BH G BH G BH A 00 Testing Program: BH P BH G

10 TABLE : SUMMARY OF GROUNDWATER LEVELS - CLARKE LANDS Strandherd Road at Cedarview Road, Ottawa (Nepean), Ontario Borehole Number Ground Elevation Measured Groundwater Level Depth Elevation Recording Date BH January 1, 010 BH January 1, 010 BH January 1, 010 BH January 1, 010 BH February 10, 011 BH February 10, 011 BH February 10, 011 BH February 10, 011 BH February 10, 011 BH February 10, 011 BH November, 00 BH November, 00 BH November, 00 BH November, 00 BH November, 00 BH November, 00 BH November, 00 BH December 11, 00 BH June 6, 006 BH June 6, 006 Notes: 1. The standpipe installations in several boreholes, that have not been recorded above, were dry and assumed to be blocked.. The reading in BH was low, compared to the depth of the base of the stiff clay crust, and is assumed to have not stabilized by the time of reading.

11 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. CME 7 Power Auger Consulting Engineers DATE February 011 PG198 BH 7 FILL: Brown silty sand with gravel, trace clay Pen. Resist. Blows/0.m 0 mm Dia. Cone Very stiff to stiff, brown SILTY CLAY W Firm to stiff, grey SILTY CLAY Dynamic Cone Penetration Test 9.7m depth End of Borehole Practical DCPT 11.07m depth 10/11)

12 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. CME 7 Power Auger Consulting Engineers DATE February 011 PG198 BH 7B 0 Pen. Resist. Blows/0.m 0 mm Dia. Cone FILL: Brown silty sand with gravel, trace clay 1. 1 Very stiff to stiff, brown SILTY CLAY End of Borehole

13 patersongroup Engineers 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. CME 7 Power Auger Consulting DATE February 011 PG198 BH 8 Loose to compact, brown SILTY SAND Pen. Resist. Blows/0.m 0 mm Dia. Cone Very stiff to stiff, brown SILTY CLAY Firm, grey SILTY CLAY Dynamic Cone Penetration Test 9.m depth. Cone pushed to 1.m depth

14 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 Consulting Engineers DATUM Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. BORINGS BY CME 7 Power Auger DATE February 011 PG198 BH Pen. Resist. Blows/0.m 0 mm Dia. Cone End of Borehole 1.6 Practical DCPT 1.6m depth (Standpipe blocked - Feb. 10/11)

15 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. CME 7 Power Auger Consulting Engineers DATE February 011 PG198 BH 9 Compact to loose, brown SILTY SAND, trace clay Pen. Resist. Blows/0.m 0 mm Dia. Cone Very stiff to stiff, brown SILTY CLAY Frim, grey SILTY CLAY Dynamic Cone Penetration Test 8.8m depth. Cone pushed to 11.m depth

16 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY Consulting Engineers Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. CME 7 Power Auger DATE February 011 PG198 BH Pen. Resist. Blows/0.m 0 mm Dia. Cone End of Borehole 1.69 Practical DCPT 1.69m depth. 10/11)

17 patersongroup Consulting Engineers 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. BORINGS BY CME 7 Power Auger DATE 8 January 011 PG198 BH10 Compact, brown SILTY SAND Pen. Resist. Blows/0.m 0 mm Dia. Cone Very stiff to stiff, brown SILTY CLAY Firm to soft, grey SILTY CLAY Dynamic Cone Penetration Test 9.m depth

18 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY Consulting Engineers Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. CME 7 Power Auger DATE 8 January 011 PG198 BH Pen. Resist. Blows/0.m 0 mm Dia. Cone End of Borehole Practical DCPT 1.m depth 1.0m-Feb. 10/11)

19 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 Consulting Engineers DATUM Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. BORINGS BY CME 7 Power Auger DATE 8 January 011 PG198 BH11 Compact to loose, brown SILTY SAND Pen. Resist. Blows/0.m 0 mm Dia. Cone Very stiff to stiff, brown SILTY CLAY Firm, grey SILTY CLAY Dynamic Cone Penetration Test 8.8m depth. Cone pushed to 1.0m depth

20 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY Consulting Engineers Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. CME 7 Power Auger DATE 8 January 011 PG198 BH Pen. Resist. Blows/0.m 0 mm Dia. Cone End of Borehole 1.7 Practical DCPT 1.7m depth 1.8m-Feb. 10/11)

21 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 Consulting Engineers DATUM Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. BORINGS BY CME 7 Power Auger DATE 1 February 011 PG198 BH1 Compact to very loose, brown SILTY SAND, trace clay Pen. Resist. Blows/0.m 0 mm Dia. Cone Very stiff to stiff, brown SILTY CLAY Firm, grey SILTY CLAY Dynamic Cone Penetration Test 9.m depth. Cone pushed to 17.m depth

22 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 Consulting Engineers DATUM Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. BORINGS BY CME 7 Power Auger DATE 1 February 011 PG198 BH Pen. Resist. Blows/0.m 0 mm Dia. Cone End of Borehole Practical DCPT 17.m depth (Standpipe blocked - Feb. 10/11)

23 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 Consulting Engineers DATUM Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. BORINGS BY CME 7 Power Auger DATE 1 January 011 PG198 BH1 Brown SILTY SAND, some clay 0.0 AU AU Pen. Resist. Blows/0.m 0 mm Dia. Cone Very stiff to stiff, brown SILTY CLAY Firm, grey SILTY CLAY Dynamic Cone Penetration Test 8.8m depth

24 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY Consulting Engineers Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. CME 7 Power Auger DATE 1 January 011 PG198 BH Pen. Resist. Blows/0.m 0 mm Dia. Cone End of Borehole Practical DCPT 1.8m depth 1.0m-Feb. 10/11)

25 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 Consulting Engineers DATUM Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. BORINGS BY CME 7 Power Auger DATE 1 January 011 PG198 BH1 Compact to loose, brown SILTY SAND, trace clay Stiff, brown SILTY CLAY Pen. Resist. Blows/0.m 0 mm Dia. Cone Soft to firm, grey SILTY CLAY Dynamic Cone Penetration Test 9.60m depth. Cone pushed to 17.0m depth

26 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY CME 7 Power Auger Consulting Engineers Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. DATE 1 January 011 PG198 BH Pen. Resist. Blows/0.m 0 mm Dia. Cone End of Borehole Practical DCPT 19.66m depth 1.0m-Feb. 10/11)

27 patersongroup 8 Concourse Gate, Unit 1, Ottawa, ON KE 7T7 DATUM BORINGS BY Consulting Engineers Ground surface elevations provided by Annis, O'Sullivan, Vollebekk Ltd. CME 7 Power Auger DATE February 011 PG198 BH1B 0 Pen. Resist. Blows/0.m 0 mm Dia. Cone Compact to loose, brown SILTY SAND, trace clay Stiff SILTY CLAY (inferred from BH 1) Soft, grey SILTY CLAY 8 End of Borehole

28 Figure 1: Elevation Profile of Shear Strength & Consolidation Minto - Clarke Lands - East Part 9.0 BH 1 BH BH 9.0 BH BH BH BH 7-0 BH 8-0 BH 9-0 Geodetic Elevation BH 1-06 BH -06 BH 7-07 BH 8-07 BH BH1- BH- BH- BH-6 BH BH6- BH7-0- BH BH9-0- BH1-06- BH Cu and pc (kpa) BH8-07- Report No. PG198-MEMO.01 March, 011 patersongroup

29 Figure : Elevation Profile of Shear Strength & Consolidation Minto - Clarke Lands - West Part 9.0 BH 7+7B BH 8 BH BH 10 BH 11 BH BH 1 BH 1+1B BH 1-0 Geodetic Elevation BH -0 BH -0 BH -0 BH -0 BH 6-0 BH -0 BH7-7 BH8-Cons BH9-Cons BH10-Cons BH11-Cons 8.0 BH1-Cons BH1-Cons BH1-Cons 80.0 BH-0- BH-0- BH Cu and pc (kpa) BH-0-Cons Report No. PG198-MEMO.01 March, 011 patersongroup

30 Figure : Depth Profile of Shear Strength & Consolidation Minto - Clarke Lands - East Part 0.0 BH 1 BH BH.0 BH BH BH 6.0 BH 7-0 BH 8-0 BH 9-0 low OGS Depth bel BH 1-06 BH -06 BH 7-07 BH 8-07 BH BH1- BH- BH- BH-6 BH BH6- BH7-0- BH BH9-0- BH1-06- BH Cu and pc (kpa) BH8-07- Report No. PG198-MEMO.01 March, 011 patersongroup

31 Figure : Depth Profile of Shear Strength & Consolidation Minto - Clarke Lands - West Part 0.0 BH 7+7B BH 8 BH 9.0 BH 10 BH 11 BH 1.0 BH 1 BH 1+1B BH 1-0 Depth be elow OGS BH -0 BH -0 BH -0 BH -0 BH 6-0 BH -0 BH7-7 BH8-Cons BH9-Cons BH10-Cons 1.0 BH11-Cons BH1-Cons BH1-Cons BH1-Cons 1.0 BH-0- BH-0- BH Cu and pc (kpa) BH-0-Cons Report No. PG198-MEMO.01 March, 011 patersongroup

patersongroup Geotechnical Investigation Proposed Commercial Development 700 Hunt Club Road Ottawa, Ontario Prepared For Lone Star Group of Companies

patersongroup Geotechnical Investigation Proposed Commercial Development 700 Hunt Club Road Ottawa, Ontario Prepared For Lone Star Group of Companies Geotechnical Engineering patersongroup Environmental Engineering Hydrogeology Geological Engineering Materials Testing Building Science Proposed Commercial Development 700 Hunt Club Road Ottawa, Ontario