Sent: Friday, June 24, :17 PM. Subject: RE: Southwood 4 - Monitoring Well update

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Charlotte Walker
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1 Sent: Friday, June 24, :17 PM Subject: RE: Southwood 4 - Monitoring Well update Please see attached for a copy of our Draft Borehole Logs, Draft Borehole Location Plan and Interim Ground Water Monitoring Update Table from the most recent field work completed at the Site. The field work included three new monitoring wells (MW6C, MW7C and MW26) within the raised Southwood 3 area, one new monitoring well (MW25B) within the homogenized area, and one new monitoring well (MW19B) to replace the previously damaged MW19A. In general, the subsurface conditions contacted during the field work were similar to our previous findings. Between 1.6 and 1.8 m of fill was contacted within the Southwood 3 area, and was typically overlying clayey silt (and silty sand in MW6C). Within the homogenized area (MW25B), 1.6 m of fill was overlying native clayey silt. It is noted that sand seams were observed within the native clayey silt layer. Southwood 3 (raised fill area) As noted, structural fill was added in the Southwood 3 areas during the 2015 construction season (approximately between May and October), and three new monitoring wells were installed in this area (MW6C adjacent to MW6A, MW7C adjacent to MW7A and MW26, near the high point of the site) to measure the effects of the added fill on the ground water levels. Below, we have tabulated the measured water levels in each of the monitoring wells installed prior to construction (i.e., MW6A and MW7A) and after construction (i.e., 6C, and 7C) for comparison purposes. For the wells that were previously installed, we have only included the ground water level measurements from the first six months of each year, for comparison purposes. Southwood 3 Ground Water Elevation MW6A (2014) MW6A (2015) MW 6C (2016) January February March April May June Average [365.76]* Minimum Maximum * Average once the January reading is removed

2 Southwood 3 Ground Water Elevation MW7A (2014) MW7A (2015) MW7C (2016) January <326.2 February March April May June ** Average * Minimum Maximum * Average once the January reading is removed ** Well damaged (buried) during construction activities Where fill was added as part of Southwood 3 construction, the ground water levels have been variable in comparison to prior ground water levels. In general, the water levels in MW7C have been similar to the ground water levels in MW7A in years past. The ground water level recorded in January within MW6C was significantly lower than in MW6A in years past, and higher in March, but similar in more recent months further monitoring is required before any conclusions can be made. Within MW26, which was also installed within the raised Southwood 3 area, the ground water levels have typically been between and m, which is below the fill / native interface. Southwood 4 (homogenized area) Within the Southwood 4 area, the client homogenized an area of the in-situ material (in January, 2016) by excavating the soil to a depth of 1.6 m, mixing it and replacing it. PML installed one monitoring well (MW25B) within the homogenized zone, adjacent to the previously installed MW25A. It is noted that sand seams were observed within the homogenized zone in the new borehole. Southwood 4 Ground Water Elevation MW25A (2015) MW25A (2016) MW25B (2016) January < February < March < April May June Average Minimum Maximum The area where the surficial soils were homogenized (MW25B) has shown higher ground water levels in recent months, compared to the closest monitoring well outside of the homogenized area (MW25A).

3 However, it is noted that MW25B is at a higher elevation than MW25A (about 0.5 m) which may account for the higher ground water level. Conclusions In both situations, the results have been mixed to this point, with potentially favourable results in the area of MW6 and neutral results elsewhere. However, PML notes that with so few data points, at least one year of monitoring results be completed prior to making any conclusions. It is noted that MW7B has been damaged as part of construction activities between April and June, and is no longer available for ground water monitoring. Should continued monitoring be required at this location, PML recommends that a new monitoring well be installed in the same general area. Mitigation measures should also be put in place to ensure that the contractor is aware of the location of all monitoring wells, and avoid any further damage. Regards, Ken Hanes, P.Eng. Project Engineer, Geotechnical and Geoenvironmental Services Peto MacCallum Ltd. 16 Franklin Street South Kitchener, Ontario N2C 1R4 Tel: (519) Fax: (519) Cell: (519) khanes@petomaccallum.com Celebrating 60 Years of Engineering Excellence! Canada s Top 100 SME since 2015

4 LOG OF BOREHOLE NO. 6C PROJECT Southwood 3 Residential Subdivision PML REF.: 12KF071 LOCATION South Parkwood Boulevard, Elmira, Ontario BORING DATE: ENGINEER K. Hanes BORING METHOD Continuous Flight Hollow Stem Augers TECHNICIAN D. Brice GROUND ELEVATION FILL: Brown clayey silt, some sand, some gravel, occasional cobbles, frozen DEPTH in METRES SOIL PROFILE DESCRIPTION SILTY SAND: Compact brown silty sand, trace gravel, moist CLAYEY SILT: Hard brown clayey silt, some sand, some gravel, APL BOREHOLE TERMINATED AT 3.5 m LEGEND NUMBER TYPE SAMPLES BLOWS/0.3m N - VALUES ELEVATION SCALE SHEAR STRENGTH C u (kpa) DYNAMIC CONE PENETRATION STANDARD PENETRATION TEST BLOWS/0.3M DRAFT LIQUID LIMIT PLASTIC LIMIT WATER CONTENT W P W W P W WATER CONTENT % UNIT WEIGHT kn/m 3 GROUND WATER OBSERVATIONS AND REMARKS Stickup with j-plug Bentonite seal 50 mm riser Filter sand Slotted screen Water Level Readings Depth: 3.0 Elevation: NOTES: LOG OF BOREHOLE REV. 08/2012 PETOMAC.GDT WATER LEVEL OBSERVED DURING / UPON COMPLETION OF DRILLING WATER LEVEL MEASURED IN MONITORING WELL UNDISTURBED FIELD VANE REMOLDED FIELD VANE LAB SHEAR TEST POCKET PENETROMETER POCKET TORVANE CHECKED BY kh

5 LOG OF BOREHOLE NO. 7C PROJECT Southwood 3 Residential Subdivision PML REF.: 12KF071 LOCATION South Parkwood Boulevard, Elmira, Ontario BORING DATE: ENGINEER K. Hanes BORING METHOD Continuous Flight Hollow Stem Augers TECHNICIAN D. Brice 0.0 DEPTH in SOIL PROFILE DESCRIPTION METRES GROUND ELEVATION FILL: Brown clayey silt, some sand, some gravel, frozen LEGEND NUMBER TYPE SAMPLES BLOWS/0.3m N - VALUES ELEVATION SCALE 366 SHEAR STRENGTH C u (kpa) DYNAMIC CONE PENETRATION STANDARD PENETRATION TEST BLOWS/0.3M LIQUID LIMIT PLASTIC LIMIT WATER CONTENT W P W W P W WATER CONTENT % UNIT WEIGHT kn/m 3 GROUND WATER OBSERVATIONS AND REMARKS CLAYEY SILT: Very stiff grey and brown mottled clayey silt, trace sand, DTPL becoming grey, APL BOREHOLE TERMINATED AT 4.3 m DRAFT Stickup with j-plug Bentonite seal 50 mm riser Filter sand Slotted screen Water Level Readings Depth: Dry Elevation: NOTES: LOG OF BOREHOLE REV. 08/2012 PETOMAC.GDT WATER LEVEL OBSERVED DURING / UPON COMPLETION OF DRILLING WATER LEVEL MEASURED IN MONITORING WELL UNDISTURBED FIELD VANE REMOLDED FIELD VANE LAB SHEAR TEST POCKET PENETROMETER POCKET TORVANE CHECKED BY kh

6 LOG OF BOREHOLE NO. 19B PROJECT Southwood 3 Residential Subdivision PML REF.: 12KF071 LOCATION South Parkwood Boulevard, Elmira, Ontario BORING DATE: ENGINEER K. Hanes BORING METHOD Continuous Flight Hollow Stem Augers TECHNICIAN D. Brice DEPTH in METRES GROUND ELEVATION SOIL PROFILE DESCRIPTION FILL: Brown clayey silt, some sand, some gravel, occasional cobbles, frozen SANDY SILT: Very dense brown sandy silt, some gravel, trace clay, damp, occasional clayey layers LEGEND NUMBER 1 TYPE SAMPLES BLOWS/0.3m N - VALUES 61 ELEVATION SCALE SHEAR STRENGTH C u (kpa) DYNAMIC CONE PENETRATION STANDARD PENETRATION TEST BLOWS/0.3M LIQUID LIMIT PLASTIC LIMIT WATER CONTENT W P W W P W WATER CONTENT % UNIT WEIGHT kn/m 3 GROUND WATER OBSERVATIONS AND REMARKS Stickup with j-plug Bentonite seal 50 mm riser Filter sand Slotted screen BOREHOLE TERMINATED AT 2.7 m /100 mm DRAFT >> Water Level Readings Depth: Dry Elevation: NOTES: LOG OF BOREHOLE REV. 08/2012 PETOMAC.GDT WATER LEVEL OBSERVED DURING / UPON COMPLETION OF DRILLING WATER LEVEL MEASURED IN MONITORING WELL UNDISTURBED FIELD VANE REMOLDED FIELD VANE LAB SHEAR TEST POCKET PENETROMETER POCKET TORVANE CHECKED BY kh

7 LOG OF BOREHOLE NO. 25B PROJECT Southwood 3 Residential Subdivision PML REF.: 12KF071 LOCATION South Parkwood Boulevard, Elmira, Ontario BORING DATE: ENGINEER K. Hanes BORING METHOD Continuous Flight Hollow Stem Augers TECHNICIAN D. Brice DEPTH in CLAYEY SILT: Firm brown and grey clayey silt, occasional sand seams, DTPL SOIL PROFILE DESCRIPTION METRES GROUND ELEVATION FILL: Brown and dark brown mottled clayey silt, some sand, APL becoming very stiff, grey BOREHOLE TERMINATED AT 3.5 m LEGEND NUMBER TYPE SAMPLES BLOWS/0.3m N - VALUES ELEVATION SCALE SHEAR STRENGTH C u (kpa) DYNAMIC CONE PENETRATION STANDARD PENETRATION TEST BLOWS/0.3M DRAFT LIQUID LIMIT PLASTIC LIMIT WATER CONTENT W P W W P W WATER CONTENT % UNIT WEIGHT kn/m 3 GROUND WATER OBSERVATIONS AND REMARKS Stickup with j-plug Bentonite seal 50 mm riser Filter sand Slotted screen Water Level Readings Depth: Dry Elevation: NOTES: LOG OF BOREHOLE REV. 08/2012 PETOMAC.GDT WATER LEVEL OBSERVED DURING / UPON COMPLETION OF DRILLING WATER LEVEL MEASURED IN MONITORING WELL UNDISTURBED FIELD VANE REMOLDED FIELD VANE LAB SHEAR TEST POCKET PENETROMETER POCKET TORVANE CHECKED BY kh

8 LOG OF BOREHOLE NO. 26 PROJECT Southwood 3 Residential Subdivision PML REF.: 12KF071 LOCATION South Parkwood Boulevard, Elmira, Ontario BORING DATE: ENGINEER K. Hanes BORING METHOD Continuous Flight Hollow Stem Augers TECHNICIAN D. Brice DEPTH in METRES GROUND ELEVATION FILL: Brown silty sand and gravel, occasional cobbles, frozen becoming brown clayey silt, some sand, trace gravel, APL CLAYEY SILT: Stiff brown clayey silt, trace sand, trace gravel, APL, occasional sand seams SOIL PROFILE DESCRIPTION BOREHOLE TERMINATED AT 4.3 m LEGEND NUMBER TYPE SAMPLES BLOWS/0.3m N - VALUES ELEVATION SCALE SHEAR STRENGTH C u (kpa) DYNAMIC CONE PENETRATION STANDARD PENETRATION TEST BLOWS/0.3M DRAFT LIQUID LIMIT PLASTIC LIMIT WATER CONTENT W P W W P W WATER CONTENT % UNIT WEIGHT kn/m 3 GROUND WATER OBSERVATIONS AND REMARKS Stickup with j-plug Bentonite seal 50 mm riser Filter sand Slotted screen Water Level Readings Depth: Dry Elevation: NOTES: LOG OF BOREHOLE REV. 08/2012 PETOMAC.GDT WATER LEVEL OBSERVED DURING / UPON COMPLETION OF DRILLING WATER LEVEL MEASURED IN MONITORING WELL UNDISTURBED FIELD VANE REMOLDED FIELD VANE LAB SHEAR TEST POCKET PENETROMETER POCKET TORVANE CHECKED BY kh

9 Ground Water Monitoring Update, Southwood 3 and Southwood 4 Residential Subdivision PML Ref.: 12KF071 June 9, /2016 GROUND WATER ELEVATION MONITORING INTERIM GROUND WATER MONITORING UPDATE Monitoring Well No. Ground Surface Elevation (m) Screen Depth (mbgs) Mid- Screen Elevation (m) and (Depth) (mbgs) 30/01/ /02/ /03/ /04/ /05/ /06/ /07/ /08/ /09/2015 Ground Water Elevation / Depth 8/11/ /12/ /01/ /03/ /04/ /06/ ~ 6.8 1A ~ ~ A ~ ~ A ~ 3.0 6B ~ 3.0 6C ~ ~ A ~ 3.8 7B ~ 3.8 7C ~ ~ 6.9 8A ~ ~ ** 6.07** 6.19** 6.16** 6.2** 6.08** ** 1.83** 1.95** 1.88** 1.96** 2.26** < < < ** ** ** 2.92** 3.15** < ** 2.26 * Page 1 of 3

10 Ground Water Monitoring Update, Southwood 3 and Southwood 4 Residential Subdivision PML Ref.: 12KF071 June 9, /2016 GROUND WATER ELEVATION MONITORING INTERIM GROUND WATER MONITORING UPDATE Monitoring Well No. Ground Surface Elevation (m) Screen Depth (mbgs) Mid- Screen Elevation (m) and (Depth) (mbgs) 30/01/ /02/ /03/ /04/ /05/ /06/ /07/ /08/ /09/2015 Ground Water Elevation / Depth 8/11/ /12/ /01/ /03/ /04/ /06/2016 9A ~ ~ A ~ ~ A ~ ~ ~ A ~ ~ A ~ ~ A ~ ~ A ~ B ~ < < * --* 11.88* --* --* --* 11* 11.5* --* 11.46* --* ** 9.66** 7.38** 7.30** 7.25** 6.55** 6.69** * < < < ** ** Page 2 of 3

11 Ground Water Monitoring Update, Southwood 3 and Southwood 4 Residential Subdivision PML Ref.: 12KF071 June 9, /2016 GROUND WATER ELEVATION MONITORING INTERIM GROUND WATER MONITORING UPDATE Monitoring Well No. Ground Surface Elevation (m) Screen Depth (mbgs) Mid- Screen Elevation (m) and (Depth) (mbgs) 30/01/ /02/ /03/ /04/ /05/ /06/ /07/ /08/ /09/2015 Ground Water Elevation / Depth 8/11/ /12/ /01/ /03/ /04/ /06/ ~ A ~ ~ A ~ ~ A ~ ~ ~ A ~ B ~ ~ * --* --* < * --* --* < *** *** *** *** *** *** *** *** *** *** *** *** < < < ** 2.8** 2.61** 2.6** 3.13** < < < < ** ** Note: m = geodetic elevation, and mbgs = metre below ground surface (values in Italic); * Monitoring well damaged by farming / construction activities ** Ground elevation changed due to topsoil stripping activities, Readings measured from top of pipe. *** No access to well due to construction activities. Monitoring well decommissioned Page 3 of 3

12 NIGHTHAWK BH 14A EL WHIPPOORWILL DRIVE N BH 14 EL STREET 'A' BH 13A EL BLOCK 104 PARK 5.354ha BH 12A EL STREET 'A' BH 6 EL BH 6A EL BH 12 STREET 'C' STREET 'B' BH 25 EL BH 25A EL BH 25B EL BH 7C EL BH 7B EL BH 7 EL BH 7A EL BH 6B EL BH 9 EL STREET 'A' BH 20A EL EL BH 9A EL BH 20 EL STREET 'C' BLOCK 101 BH 8 EL BLOCK 98 BH 8A EL SOUTH PARKWOOD BOULEVARD BH 16 EL BH 16A EL BH 1A EL STREET 'D' STREET 'A' BLOCK 102 BLOCK 99 BH 1 EL STREET 'B' BLOCK 100 BLOCK 103 BLOCK 97 BH 2A EL DRAFT BH 22 EL BH 11A EL BH 22A EL BH 11 EL BLOCK 106 STORMWATER MANAGEMENT 1.248ha BH 19 EL BH 19A EL BH 26 EL STREET 'E' BH 2 EL BH 24 EL BH 19B EL BH 6C EL BH 23A EL BH 15 EL BH 15A EL STREET 'F' BH 23 EL BURLWOOD DRIVE BUTTERNUT PLACE SOUTH PARKWOOD BLVD ARTHUR STREET HIGHWAY 86 (LISTOWEL ROAD) 0 m 40 m 80 m SCALE 120 m 160 m 200 m REFERENCE: BOREHOLE LOCATION PLAN REPRODUCED FROM DRAWING SUPPLIED BY CLIENT. NOTE: THE INFERRED STRATIGRAPHY REFERRED TO IN THE REPORT IS BASED ON THE DATA FROM THESE BOREHOLES SUPPLEMENTED BY GEOLOGICAL EVIDENCE. THE ACTUAL STRATIGRAPHY BETWEEN THE BOREHOLES MAY VARY. LEGEND: SOUTHWOOD 3 PROPOSED SOUTHWOOD 4 PROPOSED SOUTHWOOD 3 STORM WATER POND ZONE 1 ZONE 2 ZONE 3 MONITORING WELL LOCATION MONITORING WELL LOCATION (DECOMMIIONED) BIRDLAND DEVELOPMENTS LTD. c/o WALTERFEDY HYDROGEOLOGICAL MONITORING PROGRAM FOR SOUTHWOOD 3 AND SOUTHWOOD 4 RESIDENTIAL SUBDIVISION 1143 LISTOWEL ROAD, ELMIRA, ONTARIO MONITORING WELL LOCATION PLAN DRAWN CHECKED APPROVED D. BRICE K. HANES M. ALAM C O N S U L T I N G E N G I N E E R S DATE SCALE PML REF. DWG. NO. JUNE 2016 AS SHOWN 12KF071 REPORT 7 DRAWING 1

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paterson -MEMO consulting engineers paterson consulting engineers EMAIL-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